67,696 results on '"Meteorology"'
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2. Enhancing tropical cyclone intensity forecasting with explainable deep learning integrating satellite observations and numerical model outputs
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Juhyun Lee, Jungho Im, and Yeji Shin
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Earth sciences ,Atmospheric science ,Meteorology ,Applied computing in earth sciences ,Machine learning ,Science - Abstract
Summary: Tropical cyclone (TC) intensity change forecasting remains challenging due to the lack of understanding of the interactions between TC changes and environmental parameters, and the high uncertainties resulting from climate change. This study proposed hybrid convolutional neural networks (hybrid-CNN), which effectively combined satellite-based spatial characteristics and numerical prediction model outputs, to forecast TC intensity with lead times of 24, 48, and 72 h. The models were validated against best track data by TC category and phase and compared with the Korea Meteorological Administrator (KMA)-based TC forecasts. The hybrid-CNN-based forecasts outperformed KMA-based forecasts, exhibiting up to 22%, 110%, and 7% improvement in skill scores for the 24-, 48-, and 72-h forecasts, respectively. For rapid intensification cases, the models exhibited improvements of 62%, 87%, and 50% over KMA-based forecasts for the three lead times. Moreover, explainable deep learning demonstrated hybrid-CNN’s potential in predicting TC intensity and contributing to the TC forecasting field.
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- 2024
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3. Integrating Atmospheric Science Research in Chemical Education: Utility of Primary Research Articles in Fostering Student Interest in Meteorology.
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Reyes, Ronald L. and Regala, Jennifer D.
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ATMOSPHERIC sciences , *SCIENTIFIC literacy , *SCIENTIFIC literature , *PRIMARY education , *METEOROLOGY , *SCIENCE education - Abstract
Atmospheric science research has seen significant advances in facilitating the generation of knowledge and promoting a scientific understanding of global meteorological issues and concerns with the advent of technological progress across many disciplines, including the physical and biological sciences and the breakthroughs in computational and modeling methodologies. This has resulted in a rich library of scientific literature showcasing knowledge creation and a deeper understanding of natural phenomena and their linkages to the sustenance of life embodied by the extensive systems of the hydrosphere, biosphere, and even the frontiers of outer space. This article outlines how primary research in atmospheric science can be integrated into chemical education by furnishing connections and synchronicity with chemistry, bridging the concepts, discoveries, innovations, and their immediate importance to science and society. A general overview is given on how topics or themes in general chemistry courses can utilize the power of scientific research articles on atmospheric science, fostering students' interest in meteorological concepts and related fields. A non-exhaustive list of primary research literature highlighting breakthroughs related to a specific chemistry theme serving as templates for chemical educators is provided to enable the students to see real-world applications. Integrating research into science education is an effective strategy to promote scientific thinking and literacy and should be a catalyst for the global drive for sustainability. [ABSTRACT FROM AUTHOR]
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- 2023
4. Characterizing the 2020 summer floods in South China and effects on croplands
- Author
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Xi Chen, Jinwei Dong, Lin Huang, Lajiao Chen, Zhichao Li, Nanshan You, Mrinal Singha, and Fulu Tao
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Atmospheric science ,Meteorology ,Global change ,Agricultural science ,Science - Abstract
Summary: Floods occur more frequently in the context of climate change; however, flood monitoring capacity has not been well established. Here, we used a synergic mapping framework to characterize summer floods in the middle and lower reaches of the Yangtze River Plain and the effects on croplands in 2020, from both flood extent and intensity perspectives. We found that the total flood extent was 4936 km2 from July to August, and for flood intensity, 1658, 1382, and 1896 km2 of areas experienced triple, double, and single floods. A total of 2282 km2 croplands (46% of the flooded area) were inundated mainly from Poyang and Dongting Lake Basins, containing a high ratio of moderate damage croplands (47%). The newly increased flooding extent in 2020 was 29% larger than the maximum ever-flooded extent in 2015–2019. This study is expected to provide a reference for rapid regional flood disaster assessment and serving mitigation.
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- 2023
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5. Inertial instability and tropical cyclogenesis
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Thompson, Callum, Vaughan, Geraint, and Schultz, David
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551.6 ,Climatology ,Modelling ,Tropical Cyclogenesis ,Tropical Cyclone ,Reanalysis ,Dynamic Instability ,Inertial Instability ,Hydrodynamic Instability ,Instability ,Dynamic Meteorology ,Meteorology ,Atmospheric Science - Abstract
This thesis was funded by the Natural Environment Research Council (NERC) and is presented in the alternative format. The thesis comprises three separate journal articles that together form a coherent research project. The climatology of tropospheric inertial instability and the instability's effect on tropical cyclogenesis are determined in three papers. In the first paper, a hierarchy of instability criteria are derived, from which, two are used to construct global climatologies of tropospheric inertial instability using the ERA-Interim reanalysis. Seasonal occurrence maps reveal that instability is most frequent in the tropical upper troposphere of the winter hemisphere, with several local maxima of instability occurrence also identified. Synoptic composites reveal that these local maxima are associated with the midlatitude jet stream, cross-equatorial flow, and the Somali jet, as well as two previously unrecognised environments: gap wind outflow and tip jets. Furthermore, long-lived and synoptic-scale regions of instability are identified in the midlatitudes, in contrast to statements in contemporary textbooks. The effect of inertial instability on tropical cyclogenesis is then investigated via statistical and idealised numerical modelling approaches. For the statistical approach, best-track data and the ERA-Interim reanalysis are used to determine statistical relationships between inertial instability aloft and the 24-h change in mean sea-level pressure for East Pacific and North Atlantic hurricanes. No correlation is found between the spatial extent of 250-hPa instability and the 24-h intensification rates in either basin. Additionally, hypothesis testing reveals no statistical difference between the 24-h intensification rates of storms that originate in environments where the upper-tropospheric flow is predominantly inertially stable vs. storms that originate in environments where the upper-tropospheric flow contains inertial instability. Subsequently, idealised numerical modelling is used to explicitly control the inertial stability of the nascent synoptic environment via an initialised zonal jet. Although nascent synoptic environments of inertial instability are more conducive for intensification, no evidence is found to support the hypothesis that this is because the instability promotes convective outflow. Instead, we find that intensification is modulated by the environmental vertical wind shear associated with the evolution of each jet.
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- 2019
6. Evaluation and projection of precipitation extremes under 1.5°C and 2.0°C GWLs over China using bias-corrected CMIP6 models
- Author
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Junhong Guo, Yangshuo Shen, Xiuquan Wang, Xi Liang, Zhenlu Liu, and Lvliu Liu
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Atmospheric science ,Global change ,Meteorology ,Science - Abstract
Summary: China is facing an increasing challenge from severe precipitation-related extremes with accelerating global warming. In this study, using a bias-corrected CMIP6 ensemble, future responses of precipitation extreme indices at 1.5°C and 2.0°C global warming levels (GWLs) under the SSP245, SSP370 and SSP585 scenarios are investigated. Despite different change magnitudes, extreme precipitation events will be more frequent and more intense over China as a whole under higher emissions and GWLs. The increase in annual total precipitation could attribute to a sharp increase in the intensity and days of very heavy precipitation in future global warming scenarios. Limiting global warming to 1.5°C and low emission pathways (i.e., SSP245) instead of 2°C and high emission pathways (i.e., SSP585) would have substantial benefits for China in terms of reducing occurrences of extreme precipitation events.
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- 2023
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7. Ocean Dynamics: Theory And Exercises (With Solutions)
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A.S.N. Murty and A.S.N. Murty
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- Meteorology, Atmospheric science, Oceanography, Physical oceanography
- Abstract
This book on Ocean Dynamics is a comprehensive collection of materials utilized in my personal teaching at Berhampur University, University of Hyderabad, and Arbaminch University. It is primarily intended for graduate and postgraduate students studying Oceanography, physical oceanography, meteorology, atmospheric sciences, Aeronautical, Agricultural, and space meteorology, as well as various related fields in civil and ocean engineering. A distinct characteristic of this book is the inclusion of numerous exercises and their solutions under each chapter to enhance comprehension and practical application. The content of the book encompasses virtually all significant topics in physical oceanography, such as currents with and without friction, upwelling and downwelling, water masses and TS-analysis, waves and tides, Estuaries, internal waves, seiches and storm surges, and Rossby and Kelvin waves, among others. Particular emphasis is placed on recent advancements in North Indian Ocean circulation.
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- 2023
8. Climate Change in Southeast Asia and Surrounding Areas
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Song Yang, Renguang Wu, Maoqiu Jian, Jian Huang, Xiaoming Hu, Ziqian Wang, Xingwen Jiang, Song Yang, Renguang Wu, Maoqiu Jian, Jian Huang, Xiaoming Hu, Ziqian Wang, and Xingwen Jiang
- Subjects
- Atmospheric science, Climatic changes--Southeast Asia, Meteorology
- Abstract
This book is mainly focused on the climate change in Southeast Asia and its adjacent regions. It summarizes results from recent scientific research based on observational analysis, data diagnosis, theoretical analysis, and model simulations. The book covers the following research areas: (1) characteristics and mechanisms of spring–summer atmospheric circulation systems, (2) ocean-atmosphere-land interaction and climate variability, (3) climate effect of the Tibetan Plateau, (4) attribution of regional climate change and feedback/impact of regional climate on the global climate, and (5) seasonal-to-subseasonal climate prediction. It is anticipated that the book provides useful information for enhancing our understanding of the change in climate over Southeast Asia and the adjacent regions.
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- 2021
9. Sensitivity of the interannual variability of mineral aerosol simulations to meteorological forcing dataset
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Heald, Colette [Massachusetts Inst. of Technology (MIT), Cambridge, MA (United States)]
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- 2017
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10. The Wasatch Environmental Observatory: A mountain to urban research network in the semi‐arid western US.
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Follstad Shah, Jennifer J., Bares, Ryan, Bowen, Brenda B., Bowen, Gabriel J., Bowling, David R., Eiriksson, David P., Fasoli, Benjamin, Fiorella, Richard P., Hallar, Anna Gannet, Hinners, Sarah J., Horel, John D., Jacques, Alexander A., Jamison, Logan R., Lin, John C., Mendoza, Daniel L., Mitchell, Logan E., Pataki, Diane E., Skiles, Sarah McKenzie, Smith, Rose M., and Wolf, Margaret A.
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OBSERVATORIES ,URBAN research ,ATMOSPHERIC chemistry ,ATMOSPHERIC sciences ,HYDROLOGY ,AIR pollution ,SOIL structure - Abstract
The 2085 km2 Jordan River Basin, and its seven sub‐catchments draining the Central Wasatch Range immediately east of Salt Lake City, UT, are home to an array of hydrologic, atmospheric, climatic and chemical research infrastructure that collectively forms the Wasatch Environmental Observatory (WEO). WEO is geographically nested within a wildland to urban land‐use gradient and built upon a strong foundation of over a century of discharge and climate records. A 2200 m gradient in elevation results in variable precipitation, temperature and vegetation patterns. Soil and subsurface structure reflect systematic variation in geology from granitic, intrusive to mixed sedimentary clastic across headwater catchments, all draining to the alluvial or colluvial sediments of the former Lake Bonneville. Winter snowfall and spring snowmelt control annual hydroclimate, rapid population growth dominates geographic change in lower elevations and urban gas and particle emissions contribute to episodes of severe air pollution in this closed‐basin. Long‐term hydroclimate observations across this diverse landscape provide the foundation for an expanding network of infrastructure in both montane and urban landscapes. Current infrastructure supports both basic and applied research in atmospheric chemistry, biogeochemistry, climate, ecology, hydrology, meteorology, resource management and urban redesign that is augmented through strong partnerships with cooperating agencies. These features allow WEO to serve as a unique natural laboratory for addressing research questions facing seasonally snow‐covered, semi‐arid regions in a rapidly changing world and an excellent facility for providing student education and research training. [ABSTRACT FROM AUTHOR]
- Published
- 2021
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11. Climate Change and Increasing Risk of Extreme Heat
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Jones, Hunter M. and Hosokawa, Yuri, editor
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- 2018
- Full Text
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12. Using Artificial Neural Networks to Improve CFS Week-3–4 Precipitation and 2-m Air Temperature Forecasts
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Vladimir M. Krasnopolsky, Huug M. Van Den Dool, Yun Fan, Chung-Yu Wu, and Jon Gottschalck
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Atmospheric Science ,Artificial neural network ,Meteorology ,Air temperature ,Environmental science ,Metre ,Precipitation - Abstract
Forecast skill from dynamical forecast models decreases quickly with projection time due to various errors. Therefore, postprocessing methods, from simple bias correction methods to more complicated multiple linear regression–based model output statistics, are used to improve raw model forecasts. Usually, these methods show clear forecast improvement over the raw model forecasts, especially for short-range weather forecasts. However, linear approaches have limitations because the relationship between predictands and predictors may be nonlinear. This is even truer for extended range forecasts, such as week-3–4 forecasts. In this study, neural network techniques are used to seek or model the relationships between a set of predictors and predictands, and eventually to improve week-3–4 precipitation and 2-m temperature forecasts made by the NOAA/NCEP Climate Forecast System. Benefitting from advances in machine learning techniques in recent years, more flexible and capable machine learning algorithms and availability of big datasets enable us not only to explore nonlinear features or relationships within a given large dataset, but also to extract more sophisticated pattern relationships and covariabilities hidden within the multidimensional predictors and predictands. Then these more sophisticated relationships and high-level statistical information are used to correct the model week-3–4 precipitation and 2-m temperature forecasts. The results show that to some extent neural network techniques can significantly improve the week-3–4 forecast accuracy and greatly increase the efficiency over the traditional multiple linear regression methods.
- Published
- 2023
13. Characterizing Inflow Conditions Across the Rotor Disk of a Utility-Scale Wind Turbine (Poster)
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Schreck, Scott
- Published
- 2012
14. U.S. Department of Energy Workshop Report - Research Needs for Wind Resource Characterization
- Author
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Shaw, W
- Published
- 2008
15. Accounting for meteorological biases in simulated plumes using smarter metrics
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Pierre J. Vanderbecken, Joffrey Dumont Le Brazidec, Alban Farchi, Marc Bocquet, Yelva Roustan, Élise Potier, Grégoire Broquet, Centre d'Enseignement et de Recherche en Environnement Atmosphérique (CEREA), École des Ponts ParisTech (ENPC)-EDF R&D (EDF R&D), EDF (EDF)-EDF (EDF), Laboratoire des Sciences du Climat et de l'Environnement [Gif-sur-Yvette] (LSCE), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), Modélisation INVerse pour les mesures atmosphériques et SATellitaires (SATINV), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), This study has been funded by the national research project ANR-ARGONAUT no. ANR-19-CE01-0007 (PollutAnts and gReenhouse Gases emissiOns moNitoring from spAce at high ResolUTion). Joffrey Dumont Le Brazidec is supported by the European Union's Horizon 2020 research and innovation programme under grant agreement no. 958927 (Prototype system for a Copernicus CO2service). All the figures were drawn using CVD-friendly colour maps. This was made possible using a Python wrapper around Fabio Crameri's perceptually uniform colour maps , available here: https://www.fabiocrameri.ch/colourmaps/ (last access: 14 March 2023). CEREA is a member of Institut Pierre-Simon Laplace (IPSL). The authors jointly thank the associate editor, Lok Lamsal, and the two anonymous referees for the relevant comments they made during the review of this article., and ANR-19-CE01-0007,ARGONAUT,Suivi des émissions de polluants et de gaz à effet de serre à haute résolution depuis l'espace(2019)
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Atmospheric Science ,plume ,image analysis ,[SDU]Sciences of the Universe [physics] ,emission ,satellite ,environmental modeling ,meteorology ,simulation - Abstract
In the next few years, numerous satellites with high-resolution instruments dedicated to the imaging of atmospheric gaseous compounds will be launched, to finely monitor emissions of greenhouse gases and pollutants. Processing the resulting images of plumes from cities and industrial plants to infer the emissions of these sources can be challenging. In particular traditional atmospheric inversion techniques, relying on objective comparisons to simulations with atmospheric chemistry transport models, may poorly fit the observed plume due to modelling errors rather than due to uncertainties in the emissions. The present article discusses how these images can be adequately compared to simulated concentrations to limit the weight of modelling errors due to the meteorology used to analyse the images. For such comparisons, the usual pixel-wise ℒ2 norm may not be suitable, since it does not linearly penalise a displacement between two identical plumes. By definition, such a metric considers a displacement as an accumulation of significant local amplitude discrepancies. This is the so-called double penalty issue. To avoid this issue, we propose three solutions: (i) compensate for position error, due to a displacement, before the local comparison; (ii) use non-local metrics of density distribution comparison; and (iii) use a combination of the first two solutions. All the metrics are evaluated using first a catalogue of analytical plumes and then more realistic plumes simulated with a mesoscale Eulerian atmospheric transport model, with an emphasis on the sensitivity of the metrics to position error and the concentration values within the plumes. As expected, the metrics with the upstream correction are found to be less sensitive to position error in both analytical and realistic conditions. Furthermore, in realistic cases, we evaluate the weight of changes in the norm and the direction of the four-dimensional wind fields in our metric values. This comparison highlights the link between differences in the synoptic-scale winds direction and position error. Hence the contribution of the latter to our new metrics is reduced, thus limiting misinterpretation. Furthermore, the new metrics also avoid the double penalty issue.
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- 2023
16. Evaluation of extreme precipitation over Southeast Asia in the Coupled Model Intercomparison Project Phase 5 regional climate model results and HighResMIP global climate models
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Mugni Hadi Hariadi, Gerard van der Schrier, Gert‐Jan Steeneveld, Dian Nur Ratri, Ardhasena Sopaheluwakan, Albert Klein Tank, Edvin Aldrian, Dodo Gunawan, Marie‐Pierre Moine, Alessio Bellucci, Retish Senan, Etienne Tourigny, Dian Ariyani Putrasahan, and Utoyo Ajie Linarka
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R10mm ,Meteorologie en Luchtkwaliteit ,Atmospheric Science ,WIMEK ,SDII ,Meteorology and Air Quality ,CWD ,extreme precipitation ,R195pTOT ,GCM ,Rx1day ,Southeast Asia ,R20mm ,Rx5day ,CORDEX ,Meteorology ,Indonesia ,HighResMIP ,RCM ,Meteorologie ,CDD ,climate index - Abstract
Modelling rainfall extremes and dry periods over the Southeast Asia (SEA) region is challenging due to the characteristics of the region, which consists of the Maritime Continent and a mountainous region; it also experiences monsoonal conditions, as it is located between the Asian summer monsoon and the Australian summer monsoon. Representing rainfall extremes is important for flood and drought assessments in the region. This paper evaluates extreme rainfall climatic indices from regional climate models from CORDEX Southeast Asia and compares them with the results of high-resolution global climate models with a comparable spatial resolution from the HighResMIP experiment. Observations indicate a high intensity of rainfall over areas affected by tropical cyclones and long consecutive dry day periods over some areas in Indochina and the southern end of Indonesia. In the model simulations, we find that both coupled and sea surface temperature-forced HighResMIP model experiments are more similar to the observations than CORDEX model results. However, the models produce a poorer simulation of precipitation intensity-related indices due to model biases in the rainfall intensity. This bias is higher in CORDEX than in HighResMIP and is evident in both the low- and high-resolution HighResMIP model versions. The comparable performances of HighResSST (atmosphere-only runs) and Hist-1950 (coupled ocean–atmosphere runs) demonstrate the accuracy of the ocean model. Comparable performances were also found for the two different resolutions of HighResMIP, suggesting that there is no improvement in the performance of the high-resolution HighResMIP model compared to the low-resolution HighResMIP model. © 2022 The Authors. International Journal of Climatology published by John Wiley Sons Ltd on behalf of Royal Meteorological Society.
- Published
- 2023
17. The set-up and evaluation of fine-scale data assimilation for the urban climate of Amsterdam
- Author
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Sytse Koopmans, Ronald van Haren, Natalie Theeuwes, Reinder Ronda, Remko Uijlenhoet, Albert A. M. Holtslag, and Gert‐Jan Steeneveld
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Meteorologie en Luchtkwaliteit ,Atmospheric Science ,WIMEK ,Meteorology ,Meteorology and Air Quality ,Life Science ,Meteorologie - Abstract
Ongoing urbanization highlights the need for a better understanding and high resolution modelling of the urban climate. In this study, we combine rural observations by WMO surface stations, weather radar data and urban crowd-sourced observations with very fine-scale modelling efforts for Amsterdam, The Netherlands. As a model, we use the Weather Research and Forecasting (WRF) mesoscale model with 3D variational data assimilation at a 100-m resolution in the innermost model domain. In order to enable the assimilation of observations within the urban canopy, we develop a scheme to reduce urban temperature biases by adjusting urban fabric temperatures. The scheme is tested against independent urban observations for the summer month of July 2014 and specifically for a hot period and an extreme precipitation event. We find data assimilation reduces biases in temperature and wind speed. Within the city, the most significant improvement is the reduction of negative temperature biases during clear nights, which implies a better prediction of the Urban Heat Island (UHI). Concerning precipitation, the fractional skill score improves incrementally when additional observations are assimilated, and the largest impact is seen from the assimilation of weather radar observations.
- Published
- 2023
18. Image-to-Image Training for Spatially Seamless Air Temperature Estimation With Satellite Images and Station Data
- Author
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Peifeng Su, Temesgen Abera, Yanlong Guan, Petri Pellikka, and Department of Geosciences and Geography
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1171 Geosciences ,Atmospheric Science ,MODIS aqua ,Forestry ,Deep learning ,Remote sensing ,Air temperature ,Land surface ,Meteorology ,Image-to-image mapping ,Training ,Temperature sensors ,Computers in Earth Sciences ,Estimation ,Land surface temperature - Abstract
Air temperature at approximately 2 m above the ground (T-a) is one of the most important environmental and biophysical parameters to study various earth surface processes. T-a measured from meteorological stations is inadequate to study its spatio-temporal patterns since the stations are unevenly and sparsely distributed. Satellite-derived land surface temperature (LST) provides global coverage, and is generally utilized to estimate T-a due to the close relationship between LST and T-a. However, LST products are sensitive to cloud contamination, resulting in missing values in LST and leading to the estimated T-a being spatially incomplete. To solve the missing data problem, we propose a deep learning method to estimate spatially seamless T-a from LST that contains missing values. Experimental results on 5-year data of mainland China illustrate that the image-to-image training strategy alleviates the missing data problem and fills the gaps in LST implicitly. Plus, the strong linear relationships between observed daily mean T-a (T-mean), daily minimum T-a (T-min), and daily maximum T-a (T-max) make the estimation of T-mean, T-min, and T(max )simultaneously possible. For mainland China, the proposed method achieves results with R-2 of 0.962, 0.953, 0.944, mean absolute error (MAE) of 1.793 degrees C, 2.143 degrees C, and 2.125 degrees C, and root-mean-square error (RMSE) of 2.376 degrees C, 2.808 degrees C, and 2.823 degrees C for T-mean, T-min, and T-max, respectively. O
- Published
- 2023
19. Astronaut Photography: Handheld Camera Imagery from Low Earth Orbit
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Stefanov, William L., Evans, Cynthia A., Runco, Susan K., Wilkinson, M. Justin, Higgins, Melissa D., Willis, Kimberly, Pelton, Joseph N., editor, Madry, Scott, editor, and Camacho-Lara, Sergio, editor
- Published
- 2017
- Full Text
- View/download PDF
20. The effects of transboundary air pollution from China on ambient air quality in South Korea
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Moon Joon Kim
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Atmospheric science ,Air quality ,Meteorology ,Environmental analysis ,Environmental economics ,Environmental pollution ,Science (General) ,Q1-390 ,Social sciences (General) ,H1-99 - Abstract
This paper estimates the effects of wind direction on ambient air quality in South Korea (c.2006–2014) to provide insights into the impacts of the long-range transport of air pollutants from China. I find that the effect of transboundary air pollutants from China accounts for 19 percent of the weekly average PM10 concentrations, varying 12–30 percent by season. More specifically, winds blowing in the southwest direction have the largest year-round impacts on South Korea's ambient air pollution levels, which is consistent with the direction of emissions from Shanghai resulting in worse South Korean pollution levels. Further, the effects are differentiated seasonally according to the diverse activities that lead to the pollutants. Agricultural strawberry burning and coal-fired heating in northern Chinese cities lead to larger northwest wind effects in summer and winter, respectively. The winds from Shanghai have greater effects in spring due to the influence of dust storms passing from the deserts through mainland China.
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- 2019
- Full Text
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21. Isotopic compositions of ground ice in near-surface permafrost in relation to vegetation and microtopography at the Taiga–Tundra boundary in the Indigirka River lowlands, northeastern Siberia.
- Author
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Takano, Shinya, Sugimoto, Atsuko, Tei, Shunsuke, Liang, Maochang, Shingubara, Ryo, Morozumi, Tomoki, and Maximov, Trofim C.
- Subjects
- *
TUNDRAS , *COMPOSITION of water , *ICE , *PERMAFROST , *ISOTOPIC fractionation , *WATERFRONTS , *FROST heaving , *SNOW cover - Abstract
The warming trend in the Arctic region is expected to cause drastic changes including permafrost degradation and vegetation shifts. We investigated the spatial distribution of ice content and stable isotopic compositions of water in near-surface permafrost down to a depth of 1 m in the Indigirka River lowlands of northeastern Siberia to examine how the permafrost conditions control vegetation and microtopography in the Taiga–Tundra boundary ecosystem. The gravimetric water content (GWC) in the frozen soil layer was significantly higher at microtopographically high elevations with growing larch trees (i.e., tree mounds) than at low elevations with wetland vegetation (i.e., wet areas). The observed ground ice (ice-rich layer) with a high GWC in the tree mounds suggests that the relatively elevated microtopography of the land surface, which was formed by frost heave, strongly affects the survival of larch trees. The isotopic composition of the ground ice indicated that equilibrium isotopic fractionation occurred during ice segregation at the tree mounds, which implies that the ice formed with sufficient time for the migration of unfrozen soil water to the freezing front. In contrast, the isotopic data for the wet areas indicated that rapid freezing occurred under relatively non-equilibrium conditions, implying that there was insufficient time for ice segregation to occur. The freezing rate of the tree mounds was slower than that of the wet areas due to the difference of such as soil moisture and snow cover depends on vegetation and microtopography. These results indicate that future changes in snow cover, soil moisture, and organic layer, which control underground thermal conductivity, will have significant impacts on the freezing environment of the ground ice at the Taiga–Tundra boundary in northeastern Siberia. Such changes in the freezing environment will then affect vegetation due to changes in the microtopography of the ground surface. [ABSTRACT FROM AUTHOR]
- Published
- 2019
- Full Text
- View/download PDF
22. Hierarchical classification of snowmelt episodes in the Pyrenees using seismic data.
- Author
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Díaz, Jordi, Sánchez-Pastor, Pilar, and Ruiz, Mario
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- *
SNOWMELT , *RIVER channels , *AQUATIC sciences , *ATMOSPHERIC sciences , *EARTH sciences - Abstract
In recent years the analysis of the variations of seismic background signal recorded in temporal deployments of seismic stations near river channels has proved to be a useful tool to monitor river flow, even for modest discharges. The objective of this work is to apply seismic methods to the characterization of the snowmelt process in the Pyrenees, by developing an innovative approach based on the hierarchical classification of the daily spectrograms. The CANF seismic broad-band station, part of the Geodyn facility in the Laboratorio Subterráneo de Canfranc (LSC), is located in an underground tunnel in the Central Pyrenees, at about 400 m of the Aragón River channel, hence providing an excellent opportunity to explore the possibilities of the seismic monitoring of hydrological events at long term scale. We focus here on the identification and analysis of seismic signals generated by variations in river discharge due to snow melting during a period of six years (2011–2016). During snowmelt episodes, the temporal variations of the discharge at the drainage river result in seismic signals with specific characteristics allowing their discrimination from other sources of background vibrations. We have developed a methodology that use seismic data to monitor the time occurrence and properties of the thawing stages. The proposed method is based on the use of hierarchical clustering techniques to classify the daily seismic spectra according to their similarity. This allows us to discriminate up to four different types of episodes, evidencing changes in the duration and intensity of the melting process which in turn depends on variations in the meteorological and hydrological conditions. The analysis of six years of continuous seismic data from this innovative procedure shows that seismic data can be used to monitor snowmelt on long-term time scale and hence contribute to climate change studies. [ABSTRACT FROM AUTHOR]
- Published
- 2019
- Full Text
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23. Delineation of high resolution climate regions over the Korean Peninsula using machine learning approaches.
- Author
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Park, Sumin, Park, Haemi, Im, Jungho, Yoo, Cheolhee, Rhee, Jinyoung, Lee, Byungdoo, and Kwon, ChunGeun
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METEOROLOGICAL charts , *MACHINE learning , *LAND surface temperature , *CLIMATOLOGY , *ARTIFICIAL neural networks , *SNOW - Abstract
In this research, climate classification maps over the Korean Peninsula at 1 km resolution were generated using the satellite-based climatic variables of monthly temperature and precipitation based on machine learning approaches. Random forest (RF), artificial neural networks (ANN), k-nearest neighbor (KNN), logistic regression (LR), and support vector machines (SVM) were used to develop models. Training and validation of these models were conducted using in-situ observations from the Korea Meteorological Administration (KMA) from 2001 to 2016. The rule of the traditional Köppen-Geiger (K-G) climate classification was used to classify climate regions. The input variables were land surface temperature (LST) of the Moderate Resolution Imaging Spectroradiometer (MODIS), monthly precipitation data from the Tropical Rainfall Measuring Mission (TRMM) 3B43 product, and the Digital Elevation Map (DEM) from the Shuttle Radar Topography Mission (SRTM). The overall accuracy (OA) based on validation data from 2001 to 2016 for all models was high over 95%. DEM and minimum winter temperature were two distinct variables over the study area with particularly high relative importance. ANN produced more realistic spatial distribution of the classified climates despite having a slightly lower OA than the others. The accuracy of the models using high altitudinal in-situ data of the Mountain Meteorology Observation System (MMOS) was also assessed. Although the data length of the MMOS data was relatively short (2013 to 2017), it proved that the snowy, dry and cold winter and cool summer class (Dwc) is widely located in the eastern coastal region of South Korea. Temporal shifting of climate was examined through a comparison of climate maps produced by period: from 1950 to 2000, from 1983 to 2000, and from 2001 to 2013. A shrinking trend of snow classes (D) over the Korean Peninsula was clearly observed from the ANN-based climate classification results. Shifting trends of climate with the decrease/increase of snow (D)/temperate (C) classes were clearly shown in the maps produced using the proposed approaches, consistent with the results from the reanalysis data of the Climatic Research Unit (CRU) and Global Precipitation Climatology Centre (GPCC). [ABSTRACT FROM AUTHOR]
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- 2019
- Full Text
- View/download PDF
24. Evaluation of soybean genotypes for reaction to natural field infection by Cercospora species causing purple seed stain.
- Author
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Li, Shuxian, Sciumbato, Gabe, Boykin, Debbie, Shannon, Grover, and Chen, Pengyin
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SOYBEAN varieties , *SOYBEAN , *GENOTYPES , *SEEDS , *SPECIES , *PLANT breeding , *SOYBEAN diseases & pests - Abstract
Purple seed stain (PSS) of soybean (Glycine max (L.) Merr.) is a prevalent seed disease. It results in poor seed quality and reduced seed lot market grade, and thus undermines value of soybean worldwide. The objectives of this research were to evaluate the reaction of selected soybean genotypes collected from 15 countries representing maturity groups (MGs) III, IV, and V to PSS, and to identify new sources of resistance to PSS based on three years of evaluation of natural field infection by Cercospora spp. in the Mississippi Delta of the U. S. In this study, 42 soybean genotypes were evaluated in 2010, 2011, and 2012. Seventeen lines including six MG III (PI 88490, PI 504488, PI 417361, PI 548298, PI 437482, and PI 578486), seven MG IV (PI 404173, PI 346308, PI 355070, PI 416779, PI 80479, PI 346307, and PI 264555), and four MG V (PI 417567, PI 417420, PI 381659, and PI 407749) genotypes had significantly lower percent seed infection by Cercospora spp. than the susceptible checks and other genotypes evaluated (P ≤ 0.05). These genotypes of soybean can be used in developing soybean cultivars or germplasm lines with resistance to PSS and for genetic mapping of PSS resistance genes. In addition, among these 17 lines with different levels of resistance to PSS, nine soybean genotypes (PI 417361, PI 504488, PI 88490, PI 346308, PI 416779, PI 417567, PI 381659, PI 417567, and PI 407749) were previously reported as resistant to Phomopsis seed decay. Therefore, they could be useful in breeding programs to develop soybean cultivars with improved resistance to both seed diseases. [ABSTRACT FROM AUTHOR]
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- 2019
- Full Text
- View/download PDF
25. Joint emulation of Earth System Model temperature-precipitation realizations with internal variability and space-time and cross-variable correlation: fldgen v2.0 software description.
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Snyder, Abigail, Link, Robert, Dorheim, Kalyn, Kravitz, Ben, Bond-Lamberty, Ben, and Hartin, Corinne
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EMULATION software , *OPEN source software , *PHYSICAL geography , *PHYSICAL sciences , *INTEGRATED software , *COMPUTER software - Abstract
Earth System Models (ESMs) are excellent tools for quantifying many aspects of future climate dynamics but are too computationally expensive to produce large collections of scenarios for downstream users of ESM data. In particular, many researchers focused on the impacts of climate change require large collections of ESM runs to rigorously study the impacts to both human and natural systems of low-frequency high-importance events, such as multi-year droughts. Climate model emulators provide an effective mechanism for filling this gap, reproducing many aspects of ESMs rapidly but with lower precision. The R package quickly generates thousands of realizations of gridded temperature fields by randomizing the residuals of pattern scaling temperature output from any single ESM, retaining the spatial and temporal variance and covariance structures of the input data at a low computational cost. The R package described here extends this capability to produce joint realizations of multiple variables, with a focus on temperature and precipitation in an open source software package available for community use (). This substantially improves the package by removing the requirement that the ESM variables be normally distributed, and will enable researchers to quickly generate covarying temperature and precipitation data that are synthetic but faithful to the characteristics of the original ESM. [ABSTRACT FROM AUTHOR]
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- 2019
- Full Text
- View/download PDF
26. Vaginal temperature as indicative of thermoregulatory response in Nellore heifers under different microclimatic conditions.
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Oliveira, Caroline Carvalho de, Alves, Fabiana Villa, Martins, Paulo Gustavo Macedo de Almeida, Karvatte Junior, Nivaldo, Alves, Geovani Ferreira, Almeida, Roberto Giolo de, Mastelaro, Ariadne Pegoraro, and Costa e Silva, Eliane Vianna da
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HEIFERS , *ATMOSPHERIC temperature , *FOREST density , *SOLAR radiation , *TEMPERATURE - Abstract
The objective was to evaluate vaginal temperature as a thermoregulatory response of Nellore heifers under different microclimatic conditions. The study was conducted during one year in an experimental area located at 54°37′W, 20°27′S, and 530 m of altitude in Brazil. Twenty-four Nellore females were reared in integrated crop-livestock-forestry systems with different shading patterns. The randomized complete block experimental design was utilized with a sub subdivided plots scheme, with plot corresponding to the production systems, the subplot to the season of the year, and the sub subplot, the hours of the day. To characterize the microclimate, data regarding air and black globe temperatures, and air relative humidity were collected and from them, temperature-humidity index was calculated. Vaginal temperature was obtained by using a bottom-type temperature logger (i-button) attached to an adapted intravaginal device. The black-globe temperature explained the variation on vaginal temperature. Increases on vaginal temperature were only observed, on average, two hours after the increase of black-globe temperature. The microclimatic conditions found in the systems, resulting from the various tree densities, modify the vaginal temperature in different degrees, demonstrating that the shading effect is not always accompanied by improvements in thermal comfort. The system with intermediate density showed a better microclimatic condition and, consequently, a lower increase in vaginal temperature. The interaction between air temperature, humidity and solar radiation resulted in adverse environmental conditions, however, Nellore heifers showed good adaptation to the environment. In conclusion, vaginal temperature is a good indicator to evaluate the thermoregulatory response in Nellore heifers. [ABSTRACT FROM AUTHOR]
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- 2019
- Full Text
- View/download PDF
27. Machine Learning approach to Predict net radiation over crop surfaces from global solar radiation and canopy temperature data
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Saon Banerjee, Gaurav Singal, Sarathi Saha, Himanshu Mittal, Manu Srivastava, Asis Mukherjee, Sayak Mahato, Barnali Saikia, Sudipta Thakur, Suman Samanta, Riti Kushwaha, and Deepak Garg
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Machine Learning ,Atmospheric Science ,Meteorology ,Ecology ,Artificial Intelligence ,Health, Toxicology and Mutagenesis ,Temperature ,Neural Networks, Computer - Abstract
As the ground-based instruments for measuring net radiation are costly and need to be handled skillfully, the net radiation data at spatial and temporal scales over Indian subcontinent are scanty. Sometimes, it is necessary to use other meteorological parameters to estimate the value of net radiation, although the prediction may vary based on season, ground cover and estimation method. In this context, artificial intelligence can be used as a powerful tool for predicting the data considering past observed data. This paper proposes a novel method to predict the net radiation for five crop surfaces using global solar radiation and canopy temperature. This contribution includes the generation of real-time data for five crops grown in West Bengal state of India. After manual analysis and data preprocessing, data normalization has been done before applying machine learning approaches for training a robust model. We have presented the comparison in various machine learning algorithm such as ridge and spline regression, random forest, ensemble and deep neural networks. The result shows that the gradient boosting regression and ridge regression are outperforming other ML approaches. The estimated predictors enable to reduce the number of resources in terms of time, cost and manpower for proper net radiation estimation. Thus, the problem of predicting net radiation over various crop surfaces can be sorted out through ML algorithm.
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- 2022
28. 'Gray Zone' Simulations Using a Three-Dimensional Planetary Boundary Layer Parameterization in the Weather Research and Forecasting Model
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Branko Kosovic, Alberto Martilli, Timothy W. Juliano, Masih Eghdami, Pedro A. Jiménez, and Sue Ellen Haupt
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Atmospheric Science ,Meteorology ,Planetary boundary layer ,Weather Research and Forecasting Model ,Gray (horse) ,Physics::Atmospheric and Oceanic Physics ,Geology - Abstract
Generating accurate weather forecasts of planetary boundary layer (PBL) properties is challenging in many geographical regions, oftentimes due to complex topography or horizontal variability in, for example, land characteristics. While recent advances in high-performance computing platforms have led to an increase in the spatial resolution of numerical weather prediction (NWP) models, the horizontal gridcell spacing (Δx) of many regional-scale NWP models currently fall within or are beginning to approach the gray zone (i.e., Δx ≈ 100–1000 m). At these gridcell spacings, three-dimensional (3D) effects are important, as the most energetic turbulent eddies are neither fully parameterized (as in traditional mesoscale simulations) nor fully resolved [as in traditional large-eddy simulations (LES)]. In light of this modeling challenge, we have implemented a 3D PBL parameterization for high-resolution mesoscale simulations using the Weather Research and Forecasting Model. The PBL scheme, which is based on the algebraic model developed by Mellor and Yamada, accounts for the 3D effects of turbulence by calculating explicitly the momentum, heat, and moisture flux divergences in addition to the turbulent kinetic energy. In this study, we present results from idealized simulations in the gray zone that illustrate the benefit of using a fully consistent turbulence closure framework under convective conditions. While the 3D PBL scheme reproduces the evolution of convective features more appropriately than the traditional 1D PBL scheme, we highlight the need to improve the turbulent length scale formulation. Significance Statement The spatial resolution of weather models continues to increase at a rapid rate in accordance with the enhancement of computing power. As a result, smaller-scale atmospheric features become more explicitly resolved. However, most numerical models still ignore the impact of horizontal weather variations on boundary layer flows, which becomes more important at these smaller spatial scales. To address this issue, we have implemented a new modeling approach, using fundamental principles, which accounts for horizontal variability. Our results show that including three-dimensional effects of turbulence is necessary to achieve realistic boundary layer characteristics. This novel technique may be useful for many applications including complex terrain flows, pollutant dispersion, and surface–atmosphere interaction studies.
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- 2022
29. Mid-21st century air quality at the urban scale under the influence of changed climate and emissions: case studies for Paris and Stockholm
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Myrto Valari, Magnuz Engardt, Robert Vautard, Gwendoline Lacressonnière, Konstantinos Markakis, Camilla Andersson, Laboratoire de Météorologie Dynamique (UMR 8539) (LMD), Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-École polytechnique (X)-École des Ponts ParisTech (ENPC)-Centre National de la Recherche Scientifique (CNRS)-Département des Géosciences - ENS Paris, École normale supérieure - Paris (ENS-PSL), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-École normale supérieure - Paris (ENS-PSL), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL), Laboratoire des Sciences du Climat et de l'Environnement [Gif-sur-Yvette] (LSCE), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), Département des Géosciences - ENS Paris, École normale supérieure - Paris (ENS Paris), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-École normale supérieure - Paris (ENS Paris), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS)-École des Ponts ParisTech (ENPC)-École polytechnique (X)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Pierre et Marie Curie - Paris 6 (UPMC), Swedish Meteorological and Hydrological Institute (SMHI), Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ), Extrèmes : Statistiques, Impacts et Régionalisation (ESTIMR), Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ), UN-HABITAT, and Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)
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Atmospheric Science ,Ozone ,Meteorology ,010504 meteorology & atmospheric sciences ,Health impact ,Climate change ,010501 environmental sciences ,Atmospheric sciences ,7. Clean energy ,01 natural sciences ,lcsh:Chemistry ,chemistry.chemical_compound ,11. Sustainability ,[SDU.ENVI]Sciences of the Universe [physics]/Continental interfaces, environment ,Air quality index ,0105 earth and related environmental sciences ,Pollutant ,[SDU.OCEAN]Sciences of the Universe [physics]/Ocean, Atmosphere ,Global warming ,Miljövetenskap ,lcsh:QC1-999 ,chemistry ,lcsh:QD1-999 ,Homogeneous ,13. Climate action ,[SDU]Sciences of the Universe [physics] ,Environmental science ,Urban scale ,lcsh:Physics ,Environmental Sciences - Abstract
International audience; Ozone, PM10 and PM2.5 concentrations over Paris, France and Stockholm, Sweden were modeled at 4 and 1 \unit{km} horizontal resolutions respectively for the present and 2050 periods employing decade-long simulations. We account for large-scale global climate change (RCP-4.5) and fine resolution bottom-up emission projections developed by local experts and quantify their impact on future pollutant concentrations. Moreover, we identify biases related to the implementation of regional scale emission projections over the study areas by comparing modeled pollutant concentrations between the fine and coarse scale simulations. We show that over urban areas with major regional contribution (e.g., the city of Stockholm) the bias due to coarse emission inventory may be significant and lead to policy misclassification. Our results stress the need to better understand the mechanism of bias propagation across the modeling scales in order to design more successful local-scale strategies. We find that the impact of climate change is spatially homogeneous in both regions, implying strong regional influence. The climate benefit for ozone (daily average and maximum) is up to -5 % for Paris and -2 % for Stockholm city. The joined climate benefit on PM2.5 and PM10 in Paris is between -10 and -5 % while for Stockholm we observe mixed trends up to 3 % depending on season and size class. In Stockholm, emission mitigation leads to concentration reductions up to 15 % for daily average and maximum ozone and 20 % for PM and through a sensitivity analysis we show that this response is entirely due to changes in emissions at the regional scale. On the contrary, over the city of Paris (VOC-limited photochemical regime), local mitigation of NOx emissions increases future ozone concentrations due to ozone titration inhibition. This competing trend between the respective roles of emission and climate change, results in an increase in 2050 daily average ozone by 2.5 % in Paris. Climate and not emission change appears to be the most influential factor for maximum ozone concentration over the city of Paris, which may be particularly interesting in a health impact perspective.
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- 2023
30. Reconstruction of annual mean wind speed statistics at 100 m height of FINO1 and FINO2 masts with reanalyses and the geostrophic wind
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Richard Blender, Birger Tinz, Tobias Detels, and Philine Podein
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Atmospheric Science ,Meteorology ,Environmental science ,Regression analysis ,Geostrophic wind ,Wind speed - Published
- 2022
31. On the role of atmospheric simulations horizontal grid spacing for flood modeling
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Wei Zhang, Andreas F. Prein, Gabriele Villarini, Witold F. Krajewski, and Felipe Quintero
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Atmospheric Science ,Flood myth ,Meteorology ,Environmental science ,Grid - Abstract
Our study focuses on the hydrologic implications of resolving and modeling atmospheric processes at different spatial scales. Here we use heavy precipitation events from an atmospheric model that was run at different horizontal grid spacings (i.e., 250 m, 500 m, 1 km, 2 km 4 km, and 12 km) and able to resolve different processes. Within an idealized simulation framework, these rainfall events are used as input to an operational distributed hydrologic model to evaluate the sensitivity of the hydrologic response to different forcing grid spacings. We consider the finest scale (i.e., 250 m) as reference, and compute event peak flows and volumes across a wide range of basin sizes. We find that the use of increasingly-coarser inputs leads to changes in the distribution of event peak flows and volumes, with the strongest sensitivity at the smallest catchment sizes. Overall, we find that 4-km rainfall simulations represent a good compromise between computational costs and hydrologic performance, providing basic information for future endeavors geared towards regional downscaling.
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- 2022
32. Refining an ensemble of volcanic ash forecasts using satellite retrievals: Raikoke 2019
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Antonio Capponi, Cameron Saint, Helen F. Dacre, Keith Beven, Cathie A. Wells, Natalie J. Harvey, and Mike R. James
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Atmospheric Science ,Data assimilation ,Meteorology ,Internal model ,Environmental science ,Magnitude (mathematics) ,Satellite ,Statistical dispersion ,Column (database) ,Refining (metallurgy) ,Volcanic ash - Abstract
Volcanic ash advisories are produced by specialised forecasters who combine several sources of observational data and volcanic ash dispersion model outputs based on their subjective expertise. These advisories are used by the aviation industry to make decisions about where it is safe to fly. However, both observations and dispersion model simulations are subject to various sources of uncertainties that are not represented in operational forecasts. Quantification and communication of these uncertainties are fundamental for making more informed decisions. Here, we develop a data assimilation technique which combines satellite retrievals and volcanic ash transport and dispersion model (VATDM) output, considering uncertainties in both data sources. The methodology is applied to a case study of the 2019 Raikoke eruption. To represent uncertainty in the VATDM output, 1000 simulations are performed by simultaneously perturbing the eruption source parameters, meteorology and internal model parameters (known as the prior ensemble). The ensemble members are filtered, based on their level of agreement with Himawari satellite retrievals of ash column loading, to produce a posterior ensemble that is constrained by the satellite data and its uncertainty. For the Raikoke eruption, filtering the ensemble skews the values of mass eruption rate towards the lower values within the wider parameters ranges initially used in the prior ensemble (mean reduces from 1 Tg h−1 to 0.1 Tg h−1). Furthermore, including satellite observations from subsequent times increasingly constrains the posterior ensemble. These results suggest that the prior ensemble leads to an overestimate of both the magnitude and uncertainty in ash column loadings. Based on the prior ensemble, flight operations would have been severely disrupted over the Pacific Ocean. Using the constrained posterior ensemble, the regions where the risk is overestimated are reduced potentially resulting in fewer flight disruptions. The data assimilation methodology developed in this paper is easily generalisable to other short duration eruptions and to other VATDMs and retrievals of ash from other satellites.
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- 2022
33. Exploiting Aeolus level-2b winds to better characterize atmospheric motion vector bias and uncertainty
- Author
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Brett T. Hoover, Ross N. Hoffman, Hui Liu, Kayo Ide, Kevin Garrett, David Santek, and Katherine E. Lukens
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Troposphere ,Atmospheric Science ,Meteorology ,law ,Wind shear ,Geostationary orbit ,Radiosonde ,Environmental science ,Polar ,Collocation (remote sensing) ,Numerical weather prediction ,Standard deviation ,law.invention - Abstract
The need for highly accurate atmospheric wind observations is a high priority in the science community, and in particular numerical weather prediction (NWP). To address this requirement, this study leverages Aeolus wind LIDAR Level-2B data provided by the European Space Agency (ESA) to better characterize atmospheric motion vector (AMV) bias and uncertainty, with the eventual goal of potentially improving AMV algorithms. AMV products from geostationary (GEO) and low-Earth polar orbiting (LEO) satellites are compared with reprocessed Aeolus horizontal line-of-sight (HLOS) global winds observed in August and September 2019. Winds from two of the four Aeolus observing modes are utilized for comparison with AMVs: Rayleigh-clear (derived from the molecular scattering signal) and Mie-cloudy (derived from particle scattering). For the most direct comparison, quality controlled (QC’d) Aeolus winds are collocated with quality controlled AMVs in space and time, and the AMVs are projected onto the Aeolus HLOS direction. Mean collocation differences (MCD) and standard deviation (SD) of those differences (SDCD) are determined from comparisons based on a number of conditions, and their relation to known AMV bias and uncertainty estimates is discussed. GOES-16 and LEO AMV characterizations based on Aeolus winds are described in more detail. Overall, QC’d AMVs correspond well with QC’d Aeolus HLOS wind velocities (HLOSV) for both Rayleigh-clear and Mie-cloudy observing modes, despite remaining biases in Aeolus winds after reprocessing. Comparisons with Aeolus HLOSV are consistent with known AMV bias and uncertainty in the tropics, NH extratropics, and in the Arctic, and at mid- to upper-levels in both clear and cloudy scenes. SH comparisons generally exhibit larger than expected SDCD, which could be attributed to height assignment errors in regions of high winds and enhanced vertical wind shear. GOES-16 water vapor clear-sky AMVs perform best relative to Rayleigh-clear winds, with small MCD (-0.6 m s-1 to 0.1 m s-1) and SDCD (5.4–5.6 m s-1) in the NH and tropics that fall within the accepted range of AMV error values relative to radiosonde winds. Compared to Mie-cloudy winds, AMVs exhibit similar MCD and smaller SDCD (~4.4–4.8 m s-1) throughout the troposphere. In polar regions, Mie-cloudy comparisons have smaller SDCD (5.2 m s-1 in the Arctic, 6.7 m s-1 in the Antarctic) relative to Rayleigh-clear comparisons, which are larger by 1–2 m s-1. The level of agreement between AMVs and Aeolus winds varies per combination of conditions including the Aeolus observing mode coupled with AMV derivation method, geographic region, and height of the collocated winds. It is advised that these stratifications be considered in future comparison studies and impact assessments involving 3D winds. Additional bias corrections to the Aeolus dataset are anticipated to further refine the results.
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- 2022
34. Interaction of aerosol with meteorological parameters and its effect on the cash crop in the Vidarbha region of Maharashtra, India
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Navneet Kumar and Anirban Middey
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Aerosols ,Atmospheric Science ,Meteorology ,Ecology ,Health, Toxicology and Mutagenesis ,Temperature ,India ,Weather - Abstract
Regional weather variability depends on various meteorological variables such as temperature and rainfall. The current research focuses on the variability and trends in annual aerosol optical depth (AOD), temperature (T), and rainfall (RF) in 11 Vidarbha districts. The annual trend analysis of AOD, T, and R is determined using the non-parametric Sen slope and Mann-Kendall (MK) test at a 5% significant level from 1980 to 2019. Annual T and AOD indicate a substantial increase in this study, whereas rainfall shows a non-significant trend (MK, test) over the study period. According to Sen's slope trends, the relatively high rainfall area (Chandrapur = 1.273 and Garchiroli = 4.06) got positive trends, but Gondia and Bhandara districts have negative (Sen's slope = - 2.79 and - 2.56) trends. The moderate rainfall areas are showing a less negative Sen slope (Wardha = - 0.21, Washim = - 1.13 and Yavatmal = - 2.75), whereas Nagpur districts' Sen's slope shows a positive value (Sens's slope = 0.72). The assured rainfall area districts show Sen's slope trends are positive (Akola = 0.45, Amravati = 1.17 and Buldana = 0.42). Sen's slope trend indicates rising rainfall, whereas negative trends indicate decreasing rainfall in the time series. This study has also looked at the effect of RF, AOD, and T on the last two decades' cash crop production (2000-2019) for Vidarbha districts. The relationship between rainfall departure (DRF) and cash crop yield has also been highlighted. Five cash crops, such as cotton (Ct), total cereals (TCrl), total oilseeds (TOsd), total pulses (TPS), and sugarcane (Sc), are selected for the present study.
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- 2022
35. A first approach to human biometeorology research in Brazil: a systematic review and meta-analysis
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Eduardo L. Krüger, João Paulo Assis Gobo, Anderson Spohr Nedel, Fabio Luiz Teixeira Gonçalves, Paulo Sérgio Lucio, Graziela Tosini Tejas, and Marina Piacenti-Silva
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Atmospheric Science ,Meteorology ,Ecology ,Health, Toxicology and Mutagenesis ,Humans ,Morbidity ,Brazil ,Research Personnel - Abstract
This systematic review aims to give an overview of the diversity of research areas related to human biometeorology in Brazil. The main focus of this paper addresses research trends, represented by published papers with national and international authorship, main contributions and shortcomings, as well as challenges and prospects of research in this area of study. An extensive literature search was conducted in the Scopus, Web of Science, and Science Direct databases so as to identify relevant publication output up to July 2021 related to the research area. The screening resulted in 96 studies chosen for full-text reading. Overall, results indicated a reduced amount of articles on the subject matter published internationally, with noticeable gaps in research in some regions of the country, such as the Amazon region and in the Brazilian Midwest region. Research gaps in relevant areas have been identified with limited output in the climate dimensions of tourism, vector-borne diseases, mortality and morbidity in urban centers. Such gaps should further encourage researchers to engage in research focused on those areas.
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- 2022
36. Application of a ground-based microwave radiometer in aviation weather forecasting in Indian Air Force
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Shreya Pandit, Velampudi Sudarshan Srinivas, Savitesh Mishra, and Ashish Mittal
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Atmospheric Science ,Nowcasting ,Meteorology ,Correlation coefficient ,Microwave radiometer ,Weather forecasting ,computer.software_genre ,law.invention ,Freezing level ,law ,Thunderstorm ,Radiosonde ,Environmental science ,Relative humidity ,computer - Abstract
Time and intensity-specific very short-term forecasting or nowcasting is the biggest challenge faced by an aviation meteorologist. Ground-based microwave radiometer (MWR) has been used for nowcasting convective activity and it was established that there is a good comparison between thermodynamic parameters derived from MWR and GPS radiosonde observations, indicating that MWR observations can be used to develop techniques for nowcasting severe convective activity. In this study, efforts have been made to bring out the efficacy of MWR in nowcasting thunderstorms and fog. Firstly, the observations of MWR located at Palam, New Delhi, India have been compared with the nearest radiosonde data to ascertain the variation in respective profiles. Large differences were found in relative humidity (RH), whereas temperatures from MWR were found to be close to radiosonde observed temperature up to 3.5 km. Subsequently, the scatter plots and correlation coefficients of thermodynamic indices/parameters indicated that most of the parameters are either not correlated or have moderate correlation only for 12:00 UTC profiles. The superepoch technique of lagged composite for various thermodynamic indices/parameters to obtain a combined picture of all the thunderstorm and dense fog cases on the time series could not determine any pattern to predict thunderstorm and dense fog with lead time of 2-4 hours. MWR profile for a case of occurrence of thunderstorm was analyzed. No significant variation was observed in most of the indices (as calculated from MWR observed parameters) prior to the occurrence of thunderstorm. RH at freezing level and between 950 and 700 hPa levels were the only parameters, which increased four hours prior to the occurrence.
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- 2022
37. Assessment of Air Pollution in Different Areas (Urban, Suburban, and Rural) in Slovenia from 2017 to 2021
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Maja Ivanovski, Kris Alatič, Danijela Urbancl, Marjana Simonič, Darko Goričanec, and Rudi Vončina
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Atmospheric Science ,air pollution ,air quality ,air pollutants ,meteorology ,Republic of Slovenia ,Environmental Science (miscellaneous) - Abstract
Air pollution can have a significant effect on human health. The present work is focused on the investigation of daily, monthly, and annual concentration levels of five typical air pollutants (SO2, NO2, NOX, PM10, and PM2.5) in the Republic of Slovenia (RS) from January 2017 to December 2021. The study was conducted at five different monitoring stations of the following kind: traffic (A), industrial (D), and background (B, C, E). The obtained results showed a decline in the average concentrations for all the studied air pollutants through the years, respectively. The daily average SO2 concentrations were the lowest in the year 2021 at location B, which is classified as background location, while the highest were detected in the year 2018 at location E, which is also classified as background location. The average daily concentrations of NO2 and NOX were the highest at location A in the year 2017, whereas the lowest were detected in the year 2010 and 2021. It is believed that those results are a consequence of measures set by the Slovenian government during the COVID-19 pandemic. The PM10 and PM2.5 daily average concentrations were the highest at location A in 2017, while the lowest were observed in the year 2019 at location C. Meteorological parameters (temperature, wind speed, and relative humidity) were studied in addition. In general, the high temperatures in ambient air are responsible for the intense concentrations of air pollutants. It was found in the study results for temperature, wind speed, and relative humidity that no significant difference was shown between studied years.
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- 2023
- Full Text
- View/download PDF
38. Brochosomes and Other Bioaerosols in the Surface Layer of the Atmosphere of Moscow Metropolis
- Author
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Dina P. Gubanova, Anna A. Vinogradova, and Nataliya V. Sadovskaya
- Subjects
Atmospheric Science ,atmosphere ,Moscow ,urban aerosol ,primary biological aerosol ,brochosomes ,morphology ,meteorology ,Environmental Science (miscellaneous) - Abstract
The paper presents the results of the morphological study of aerosol particles in the urban air of Moscow (Russia) in 2019–2022 by scanning electron microscopy (SEM). Our monitoring revealed mineral and anthropogenic particles, and also primary bioaerosols (PBA), such as pollen, spores, plant fibers, etc., typical for the urban environment. Moreover, in July 2021, brochosomes, lipid secretions of semi-hard-winged insects Cicadellidae (or leafhopper), were found in several aerosol samples. They are quasi-spherical hollow porous semi-regular polyhedra (truncated icosahedra) of 0.2–0.7 microns in size, consisting mainly of carbon and oxygen. Despite the prevalence and diversity of leafhoppers, identification of their secretions in atmospheric aerosols in situ is rather rare: single articles from South Korea, Spain, the Himalayas, and the United States. In this sense, the results obtained are interesting and novel. PBA particles cover a wide size range and have a complex and diverse shape, which determines the distance and efficiency of their atmospheric transport. Pollen and fungal spores have a high allergenic potential and can have harmful effects on human health. Any new information about PBA can be useful for studying the development and dynamics of ecosystems.
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- 2023
- Full Text
- View/download PDF
39. Diurnal variability of atmospheric O2, CO2 and their exchange ratio above a boreal forest in southern Finland
- Author
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Kim A. P. Faassen, Linh N. T. Nguyen, Eadin R. Broekema, Bert A. M. Kers, Ivan Mammarella, Timo Vesala, Penelope A. Pickers, Andrew C. Manning, Jordi Vilà-Guerau de Arellano, Harro A. J. Meijer, Wouter Peters, Ingrid T. Luijkx, Institute for Atmospheric and Earth System Research (INAR), Micrometeorology and biogeochemical cycles, Viikki Plant Science Centre (ViPS), and Ecosystem processes (INAR Forest Sciences)
- Subjects
Meteorologie en Luchtkwaliteit ,Atmospheric Science ,WIMEK ,Meteorology and Air Quality ,Respiration ,Sulfide ,Climate ,Tall tower ,Luchtkwaliteit ,O-2/n-2 ,Air Quality ,Oxygen ,Meteorology ,Fluxes ,Gas ,Carbon-dioxide ,Life Science ,Nitrate assimilation ,Meteorologie ,1172 Environmental sciences - Abstract
The exchange ratio (ER) between atmospheric O2 and CO2 is a useful tracer for better understanding the carbon budget on global and local scales. The variability of ER (in mol O2 per mol CO2) between terrestrial ecosystems is not well known, and there is no consensus on how to derive the ER signal of an ecosystem, as there are different approaches available, either based on concentration (ERatmos) or flux measurements (ERforest). In this study we measured atmospheric O2 and CO2 concentrations at two heights (23 and 125 m) above the boreal forest in Hyytiälä, Finland. Such measurements of O2 are unique and enable us to potentially identify which forest carbon loss and production mechanisms dominate over various hours of the day. We found that the ERatmos signal at 23 m not only represents the diurnal cycle of the forest exchange but also includes other factors, including entrainment of air masses in the atmospheric boundary layer before midday, with different thermodynamic and atmospheric composition characteristics. To derive ERforest, we infer O2 fluxes using multiple theoretical and observation-based micro-meteorological formulations to determine the most suitable approach. Our resulting ERforest shows a distinct difference in behaviour between daytime (0.92 ± 0.17 mol mol−1) and nighttime (1.03 ± 0.05 mol mol−1). These insights demonstrate the diurnal variability of different ER signals above a boreal forest, and we also confirmed that the signals of ERatmos and ERforest cannot be used interchangeably. Therefore, we recommend measurements on multiple vertical levels to derive O2 and CO2 fluxes for the ERforest signal instead of a single level time series of the concentrations for the ERatmos signal. We show that ERforest can be further split into specific signals for respiration (1.03 ± 0.05 mol mol−1) and photosynthesis (0.96 ± 0.12 mol mol−1). This estimation allows us to separate the net ecosystem exchange (NEE) into gross primary production (GPP) and total ecosystem respiration (TER), giving comparable results to the more commonly used eddy covariance approach. Our study shows the potential of using atmospheric O2 as an alternative and complementary method to gain new insights into the different CO2 signals that contribute to the forest carbon budget.
- Published
- 2023
40. Field comparison of two novel open-path instruments that measure dry deposition and emission of ammonia using flux-gradient and eddy covariance methods
- Author
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Daan Swart, Jun Zhang, Shelley van der Graaf, Susanna Rutledge-Jonker, Arjan Hensen, Stijn Berkhout, Pascal Wintjen, René van der Hoff, Marty Haaima, Arnoud Frumau, Pim van den Bulk, Ruben Schulte, Margreet van Zanten, and Thomas van Goethem
- Subjects
Meteorologie en Luchtkwaliteit ,Atmospheric Science ,WIMEK ,Meteorology ,Meteorology and Air Quality ,Life Science ,Meteorologie - Abstract
Dry deposition of ammonia (NH3) is the largest contributor to the nitrogen deposition from the atmosphere to soil and vegetation in the Netherlands, causing eutrophication and loss of biodiversity; however, data sets of NH3 fluxes are sparse and in general have monthly resolution at best. An important reason for this is that measurement of the NH3 flux under dry conditions is notoriously difficult. There is no technique that can be considered as the gold standard for these measurements, which complicates the testing of new techniques. Here, we present the results of an intercomparison of two novel measurement set-ups aimed at measuring dry deposition of NH3 at half hourly resolution. Over a 5-week period, we operated two novel optical open-path techniques side by side at the Ruisdael station in Cabauw, the Netherlands: the RIVM-miniDOAS 2.2D using the aerodynamic gradient technique, and the commercial Healthy Photon HT8700E using the eddy covariance technique. These instruments are widely different in their measurement principle and approach to derive deposition values from measured concentrations; however, both techniques showed very similar results (r=0.87) and small differences in cumulative fluxes (∼ 10 %) as long as the upwind terrain was homogeneous and free of nearby obstacles. The observed fluxes varied from ∼ −80 to ∼ +140 ng NH3 m−2 s−1. Both the absolute flux values and the temporal patterns were highly similar, which substantiates that both instruments were able to measure NH3 fluxes at high temporal resolution. However, for wind directions with obstacles nearby, the correlations between the two techniques were weaker. The uptime of the miniDOAS system reached 100 % once operational, but regular intercalibration of the system was applied in this campaign (35 % of the 7-week uptime). Conversely, the HT8700E did not measure during and shortly after rain, and the coating of its mirrors tended to degrade (21 % data loss during the 5-week uptime). In addition, the NH3 concentrations measured by the HT8700E proved sensitive to air temperature, causing substantial differences (range: −15 to +6 µg m−3) between the two systems. To conclude, the miniDOAS system appears ready for long-term hands-off monitoring. The current HT8700E system, on the other hand, had a limited stand-alone operational time under the prevailing weather conditions. However, under relatively dry and low-dust conditions, the system can provide sound results, opening good prospects for future versions, also for monitoring applications. The new high temporal resolution data from these instruments can facilitate the study of processes behind NH3 dry deposition, allowing an improved understanding of these processes and better parameterisation in chemical transport models.
- Published
- 2023
41. Reconciling Observations of Solar Irradiance Variability With Cloud Size Distributions
- Author
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Wouter B. Mol, Bart J. H. van Stratum, Wouter H. Knap, and Chiel C. van Heerwaarden
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Meteorologie en Luchtkwaliteit ,Atmospheric Science ,Physics - Atmospheric and Oceanic Physics ,Geophysics ,WIMEK ,Meteorology ,Meteorology and Air Quality ,Space and Planetary Science ,Atmospheric and Oceanic Physics (physics.ao-ph) ,Earth and Planetary Sciences (miscellaneous) ,FOS: Physical sciences ,Life Science ,Meteorologie - Abstract
Clouds cast shadows on the surface and locally enhance solar irradiance by absorbing and scattering sunlight, resulting in fast and large solar irradiance fluctuations on the surface. Typical spatiotemporal scales and driving mechanisms of this intra-day irradiance variability are not well known, hence even one day ahead forecasts of variability are inaccurate. Here we use long term, high frequency solar irradiance observations combined with satellite imagery, numerical simulations, and conceptual modelling to show how irradiance variability is linked to the cloud size distribution. Cloud shadow sizes are distributed according to a power law over multiple orders of magnitude, deviating only from the cloud size distribution due to cloud edge transparency at scales below 750 meters. Locally cloud-enhanced irradiance occurs as frequently as shadows, and is similarly driven mostly by boundary layer clouds, but distributed over a smaller range of scales. We reconcile studies of solar irradiance variability with those on clouds, which brings fundamental understanding to what drives irradiance variability. Our findings have implications for not only for weather and climate modelling, but also for solar energy and photosynthesis by vegetation, where detailed knowledge of surface solar irradiance is essential., Implemented peer review feedback, with many textual clarifications, an extra figure, and improved discussion of results
- Published
- 2023
42. Assessing the simulation of snowfall at Dumont d'Urville, Antarctica, during the <scp>YOPP‐SH</scp> special observing campaign
- Author
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Marie‐Laure Roussel, Valentin Wiener, Christophe Genthon, Etienne Vignon, Eric Bazile, Cécile Agosta, Alexis Berne, Claudio Durán‐Alarcón, Jean‐Louis Dufresne, Chantal Claud, Laboratoire de Météorologie Dynamique (UMR 8539) (LMD), Institut national des sciences de l'Univers (INSU - CNRS)-École polytechnique (X)-École des Ponts ParisTech (ENPC)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Département des Géosciences - ENS Paris, École normale supérieure - Paris (ENS-PSL), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-École normale supérieure - Paris (ENS-PSL), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL), Centre national de recherches météorologiques (CNRM), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Centre National de la Recherche Scientifique (CNRS), Laboratoire des Sciences du Climat et de l'Environnement [Gif-sur-Yvette] (LSCE), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), Glaces et Continents, Climats et Isotopes Stables (GLACCIOS), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), Environmental Remote Sensing Laboratory [Lausanne], Ecole Polytechnique Fédérale de Lausanne (EPFL), Centre for Environmental and Marine Studies [Aveiro] (CESAM), and Universidade de Aveiro
- Subjects
Atmospheric Science ,surface mass-balance ,boundary-layer ,antarctica ,vertical structure ,snowfall ,precipitation ,[SDU.STU.ME]Sciences of the Universe [physics]/Earth Sciences/Meteorology ,stations ,coastal adelie land ,mar ,precipitation radar ,observations ,yopp ,east antarctica ,drifting-snow ,meteorology ,climate - Abstract
International audience; The performance of a set of atmospheric models and meteorological reanalyses in the representation of precipitation days in Antarctica is assessed using ground-based observations such as a precipitation gauge and a Micro Rain Radar during the Year Of Polar Prediction Special Observing Period at Dumont d'Urville (November 2018 - February 2019), East Antarctic coast. The occurrence of precipitation is overall well predicted but the number of days and intensity with snowfall are overestimated by the models. This is reflected by high values of bias, probability of detection and false alarm ratios, in particular for reanalyses, due to too frequent simulated precipitating days. The Heidke skill score shows the overall great contribution of the models in the forecasting of precipitating days, and the best performances are achieved by numerical weather prediction models. The chronology is better represented when the models benefit from the data assimilation of in-situ observations, such as in reanalysis or weather forecasting models. Precipitation amounts at the surface are overestimated by most of the models. In addition, data from a ground-based radar make it possible to evaluate the representation of the vertical profiles of snowfall rate. We can show that an excessive sublimation in the atmospheric boundary layer can compensate for overly strong precipitation flux in the mid and low troposphere. Therefore the need to expand the measurement of precipitation across the atmospheric column using radars is highlighted, in particular in Antarctica where the cold cloud microphysics is poorly known and observations are particularly rare.
- Published
- 2023
43. Low ozone dry deposition rates to sea ice during the MOSAiC field campaign: Implications for the Arctic boundary layer ozone budget
- Author
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Johannes G.M. Barten, Laurens N. Ganzeveld, Gert-Jan Steeneveld, Byron W. Blomquist, Hélène Angot, Stephen D. Archer, Ludovic Bariteau, Ivo Beck, Matthew Boyer, Peter von der Gathen, Detlev Helmig, Dean Howard, Jacques Hueber, Hans-Werner Jacobi, Tuija Jokinen, Tiia Laurila, Kevin M. Posman, Lauriane Quéléver, Julia Schmale, Matthew D. Shupe, Maarten C. Krol, Deming, Jody W, and Miller, Lisa A
- Subjects
Atmospheric Science ,Arctic ozone ,WIMEK ,Environmental Engineering ,Ecology ,Ozone deposition ,Geology ,Luchtkwaliteit ,Atmospheric boundary layer ,Geotechnical Engineering and Engineering Geology ,Oceanography ,Modelling ,Air Quality ,Meteorology ,Life Science ,Meteorologie - Abstract
Dry deposition to the surface is one of the main removal pathways of tropospheric ozone (O3). We quantified for the first time the impact of O3 deposition to the Arctic sea ice on the planetary boundary layer (PBL) O3 concentration and budget using year-round flux and concentration observations from the Multidisciplinary drifting Observatory for the Study of Arctic Climate (MOSAiC) campaign and simulations with a single-column atmospheric chemistry and meteorological model (SCM). Based on eddy-covariance O3 surface flux observations, we find a median surface resistance on the order of 20,000 s m−1, resulting in a dry deposition velocity of approximately 0.005 cm s−1. This surface resistance is up to an order of magnitude larger than traditionally used values in many atmospheric chemistry and transport models. The SCM is able to accurately represent the yearly cycle, with maxima above 40 ppb in the winter and minima around 15 ppb at the end of summer. However, the observed springtime ozone depletion events are not captured by the SCM. In winter, the modelled PBL O3 budget is governed by dry deposition at the surface mostly compensated by downward turbulent transport of O3 towards the surface. Advection, which is accounted for implicitly by nudging to reanalysis data, poses a substantial, mostly negative, contribution to the simulated PBL O3 budget in summer. During episodes with low wind speed (
- Published
- 2023
44. Evaluation of downscaling seasonal climate forecasts for crop yield forecasting in Zimbabwe
- Author
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S. Chinyoka and G.J. Steeneveld
- Subjects
Zimbabwe ,Meteorologie en Luchtkwaliteit ,Atmospheric Science ,Global and Planetary Change ,WIMEK ,Meteorology and Air Quality ,WRF ,Crop ,WOFOST ,Seasonal forecasting ,Meteorology ,Water Systems and Global Change ,CFSv2 ,Meteorologie - Abstract
Meteorology and weather forecasting are crucial for water-limited agriculture. We evaluate the added value of downscaling seven-months global deterministic seasonal forecasts from the Climate Forecast System version 2 (CFSv2) using the Weather, Research and Forecasting (WRF) model over Zimbabwe for ten growing seasons (2011–2021). Downscaling reduces the area of significant differences between forecasted and observed total seasonal rainfall. Downscaling also improves the score for droughts as measured through the standardized precipitation index and 3-class method. Yield forecasts by the WOrld FOod STudies (WOFOST) model reveal that downscaling improves the estimated growing season evolution and maize yield in all studied regions across the country. For the main maize production region Karoi, the bias, root mean square error, mean absolute error and mean absolute percentage error reduce by 33% (0.2 ton/ha), 27% (0.4 ton/ha), 31% (0.4 ton/ha) and 27% (8.3 %) respectively by downscaling. Hence we illustrate that downscaling the deterministic seasonal forecasts may assist in food security in a crucial area in southern Africa.
- Published
- 2023
45. Correction to: The Impact of Three-Dimensional Effects on the Simulation of Turbulence Kinetic Energy in a Major Alpine Valley
- Author
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Brigitta Goger, Mathias W. Rotach, Alexander Gohm, Oliver Fuhrer, Ivana Stiperski, and Albert A. M. Holtslag
- Subjects
Atmospheric Science ,WIMEK ,Meteorology ,Life Science ,Meteorologie - Abstract
The funding agency information in the Acknowledgements was not complete in the original publication of the article. The revised Acknowledgments is provided in this erratum.
- Published
- 2023
46. Midday Boundary-Layer Collapse in the Altiplano Desert : The Combined Effect of Advection and Subsidence
- Author
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Francisca Aguirre Correa, Jordi Vilà-Guerau de Arellano, Reinder Ronda, Felipe Lobos Roco, Francisco Suárez, and Oscar Hartogensis
- Subjects
Meteorologie en Luchtkwaliteit ,Atmospheric Science ,Boundary-layer collapse ,WIMEK ,Meteorology ,Altiplano ,Meteorology and Air Quality ,WRF ,Advection ,Meteorologie ,CLASS - Abstract
Observations in the Altiplano region of the Atacama Desert show that the atmospheric boundary layer (ABL) suddenly collapses at noon. This rapid decrease occurs simultaneously to the entrance of a thermally driven, regional flow that causes a rise in wind speed and a marked temperature decrease. We identify the main drivers that cause the observed ABL collapse by using a land–atmosphere model. The free atmosphere lapse rate and regional forcings, such as advection of mass and cold air as well as subsidence, are first estimated by combining observations from a comprehensive field campaign and a regional model. Then, to disentangle the ABL collapse, we perform a suite of numerical experiments with increasing level of complexity: from only considering local land–atmosphere interactions, to systematically including the regional contributions of mass advection, cold air advection, and subsidence. Our results show that non-local processes related to the arrival of the regional flow are the main factors explaining the boundary-layer collapse. The advection of a shallower boundary layer ($$\approx -250$$ ≈ - 250 m h$$^{-1}$$ - 1 at noon) causes an immediate decrease in the ABL height (h) at midday. This occurs simultaneously with the arrival of a cold air mass, which reaches a strength of $$\approx -4$$ ≈ - 4 K h$$^{-1}$$ - 1 at 1400 LT. These two external forcings become dominant over entrainment and surface processes that warm the atmosphere and increase h. As a consequence, the ABL growth is capped during the afternoon. Finally, a wind divergence of $$\approx 8 \times 10^{-5}$$ ≈ 8 × 10 - 5 s$$^{-1}$$ - 1 contributes to the collapse by causing subsidence motions over the ABL from 1200 LT onward. Our findings show the relevance of treating large and small-scale processes as a continuum to be able to understand the ABL dynamics.
- Published
- 2023
47. Investigating the impact of sea surface temperature on the development of the Mediterranean tropical-like cyclone 'Ianos' in 2020
- Author
-
Varlas, George, Pytharoulis, Ioannis, Steeneveld, Gert Jan, Katsafados, Petros, and Papadopoulos, Anastasios
- Subjects
Medicane ,Atmospheric Science ,Extreme weather ,WIMEK ,Meteorology ,Air-sea interaction ,Phase-space diagrams ,WRF ,Meteorologie ,SST - Abstract
This study aims to unravel and quantify the impact of sea surface temperature (SST) on the formation, intensity, structure and track of the Mediterranean tropical-like cyclone (medicane) Ianos occurred on 15–20 September 2020 at the central Mediterranean. This study, thus, demonstrates how Ianos would be in past and future climate conditions, assuming that SST changes over the years, but preserving the same atmospheric conditions. To investigate the SST impact, the medicane was simulated using the Advanced Weather and Research Forecasting (WRF-ARW) model. The numerical experiments were initialized either with SST analysis data (control experiment) or applying a uniform decrease and increase to SST analysis by 1 °C and 2 °C (four sensitivity experiments). In this way, the past and future climatic SSTs were concisely approximated. Analysis of various thermodynamic parameters in combination with phase space diagrams, revealing the thermal symmetry and the warm core structure of the cyclone, indicated that Ianos was very sensitive on SST. Thus, SST changes especially by ±2 °C had significant impact on its intensity, changing the period of tropical features while also determining the track and the landfall location. Overall, the average enthalpy flux (i.e., the sum of sensible and latent heat fluxes) in Ianos changed by approximately −39% and + 50% when SST changed by −2 °C and + 2 °C, respectively. This, in turn, affected the characteristics of Ianos causing changes for example in the average wind speed (approximately −15% and + 15%) and the average precipitation (approximately −56% and + 44%). This study quantifies the impacts of SST on Ianos medicane that have important research and socioeconomic implications with a view to a changing future. Therefore, it could support scientists, decision-makers and civil protection in the adaptation to extreme weather phenomena by building climate resilience and sustainability.
- Published
- 2023
48. The CrowdWater game: A playful way to improve the accuracy of crowdsourced water level class data.
- Author
-
Strobl, Barbara, Etter, Simon, van Meerveld, Ilja, and Seibert, Jan
- Subjects
- *
WATER levels , *QUALITY control , *CITIZEN science , *WATER use , *DATA quality , *SCIENTISTS , *GAMES - Abstract
Data quality control is important for any data collection program, especially in citizen science projects, where it is more likely that errors occur due to the human factor. Ideally, data quality control in citizen science projects is also crowdsourced so that it can handle large amounts of data. Here we present the CrowdWater game as a gamified method to check crowdsourced water level class data that are submitted by citizen scientists through the CrowdWater app. The app uses a virtual staff gauge approach, which means that a digital scale is added to the first picture taken at a site and this scale is used for water level class observations at different times. In the game, participants classify water levels based on the comparison of the new picture with the picture containing the virtual staff gauge. By March 2019, 153 people had played the CrowdWater game and 841 pictures were classified. The average water level for the game votes for the classified pictures was compared to the water level class submitted through the app to determine whether the game can improve the quality of the data submitted through the app. For about 70% of the classified pictures, the water level class was the same for the CrowdWater app and game. For a quarter of the classified pictures, there was disagreement between the value submitted through the app and the average game vote. Expert judgement suggests that for three quarters of these cases, the game based average value was correct. The initial results indicate that the CrowdWater game helps to identify erroneous water level class observations from the CrowdWater app and provides a useful approach for crowdsourced data quality control. This study thus demonstrates the potential of gamified approaches for data quality control in citizen science projects. [ABSTRACT FROM AUTHOR]
- Published
- 2019
- Full Text
- View/download PDF
49. Decontamination of aerosolised bacteria from a pig farm environment using a pH neutral electrochemically activated solution (Ecas4 anolyte).
- Author
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Tenzin, Sangay, Ogunniyi, Abiodun David, Khazandi, Manouchehr, Ferro, Sergio, Bartsch, Jonathon, Crabb, Simon, Abraham, Sam, Deo, Permal, and Trott, Darren J.
- Subjects
- *
SWINE farms , *SWINE , *FARMS & the environment , *MICROBIOLOGICAL aerosols , *ELECTROLYTIC cells , *PROPIDIUM monoazide , *FORMALDEHYDE - Abstract
An electrochemically activated solution (ECAS), generated by electrolysis of a dilute sodium chloride solution in a four-chamber electrolytic cell (Ecas4), was tested as a sanitising aerosol in eliminating bacteria from the environment of a weaning room vacated 24-48h earlier, at a continuous flow pig farm. An ultrasonic humidifier was used to fill the environment with a fog (droplets with diameters of 1–5 μm) containing 0.25 ppm of hypochlorous acid. The weaning room was fogged for 3 min at 30 min intervals during five hours of aerosol disinfection. An innovative sample treatment with propidium monoazide dye in conjunction with cyclonic air sampling was optimised and adapted for discerning live/dead bacteria in subsequent molecular quantification steps. Without fogging, total bacterial load ranged from 5.06 ± 0.04 to 5.75 ± 0.04 Log10 CFU/m3. After the first hour of fogging, a 78% total bacterial reduction was observed, which further increased to > 97% after the second hour, > 99.4% after the third and 99.8% after the fourth hour, finally resulting in a 99.99% reduction from the farm environment over five hours. Unlike the current formaldehyde spray disinfection protocol, which requires a long empty period because of its hazardous properties, this economically viable and environmentally friendly disinfection protocol may significantly lower downtime. Moreover, ECAS fogging can be easily adapted to a variety of applications, including the elimination of pathogens from livestock farm air environment for disease prevention, as well as decontamination after disease outbreaks. [ABSTRACT FROM AUTHOR]
- Published
- 2019
- Full Text
- View/download PDF
50. Intrinsic and extrinsic drivers of transmission dynamics of hemorrhagic fever with renal syndrome caused by Seoul hantavirus.
- Author
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Li, Yidan, Cazelles, Bernard, Yang, Guoqing, Laine, Marko, Huang, Zheng X. Y., Cai, Jun, Tan, Hua, Stenseth, Nils Chr., and Tian, Huaiyu
- Subjects
- *
HEMORRHAGIC fever with renal syndrome , *RATTUS norvegicus , *POPULATION dynamics , *INFECTIOUS disease transmission , *CLIMATE change - Abstract
Seoul hantavirus (SEOV) has recently raised concern by causing geographic range expansion of hemorrhagic fever with renal syndrome (HFRS). SEOV infections in humans are significantly underestimated worldwide and epidemic dynamics of SEOV-related HFRS are poorly understood because of a lack of field data and empirically validated models. Here, we use mathematical models to examine both intrinsic and extrinsic drivers of disease transmission from animal (the Norway rat) to humans in a SEOV-endemic area in China. We found that rat eradication schemes and vaccination campaigns, but below the local elimination threshold, could diminish the amplitude of the HFRS epidemic but did not modify its seasonality. Models demonstrate population dynamics of the rodent host were insensitive to climate variations in urban settings, while relative humidity had a negative effect on the seasonality in transmission. Our study contributes to a better understanding of the epidemiology of SEOV-related HFRS, demonstrates asynchronies between rodent population dynamics and transmission rate, and identifies potential drivers of the SEOV seasonality. [ABSTRACT FROM AUTHOR]
- Published
- 2019
- Full Text
- View/download PDF
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