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This study provides an assessment of the current and future changes (in terms of both direction and value) in air temperature, precipitation, snow, wind and their extremes over the territory of Belarus using information from 42 meteorological stations and 92 regional circulation model (RCM) simulations with the highest available horizontal resolution (EUR-11). Three representative concentration pathway scenarios, namely, RCP2.6, RCP4.5 and RCP8.5, are considered. Results demonstrate that in recent decades, temperature has increased over the territory of Belarus by 1.3°C, with the largest increase occurring during the cold season (2.1-2.3°C). Ensemble scenarios project further increases in air temperature in the current century by +0.5-1.5°C, +2.8°C, and +5.2°C under the RCP2.6, RCP4.5 and RCP8.5 scenarios, with the largest increase during the cold season under the RCP8.5 scenario. The annual means were observed to increase (insignificantly) by 5-7% and the summer precipitation extremes exhibited a 20-25% growth in recent decades. Moreover, dry conditions have intensified in Belarus, particularly during the growing season. Further increases in precipitation of 10-15% across Belarus are projected to occur in all seasons under the RCP4.5 and RCP8.5 scenarios. Simulation models predict greater increases in single day rainfall events compared to their multiday precipitation counterparts. The greatest increases in maximal dry period length (by 1-2) are expected to occur in summer and autumn. The models project the general decrease in snowfall across Belarus to continue into the current century, with a reduction in snow precipitation days of 10-30 days. Despite the reduced wind strength (by 0.9-1.0 m·s-1) since the 1970s over the territory of Belarus, the ensemble model reveals slight nonsignificant changes in seasonal and annual wind strengths until the end of the century. Significant changes of 1-3 days under varying directions of the wind regime were observed for days with a strong breeze and storms. [ABSTRACT FROM AUTHOR]

According to the geographic latitude and proximity to the Aegean and Adriatic Sea, in a sense Macedonia belongs to the Mediterranean climate, but because of the stress relief it has a variable climate. These climatic features are presented with essentially the Pollog hollow where Sharr, Korab, and Rudoka mountains, on the border with Albania, measures to prevent infiltration of humid air coming from the Adriatic Sea. Therefore, due to this the Pollog hollow is characterized with not a lot of precipitation such as the Adriatic coast. The distribution of air pressure has significant influence on thermal conditions and climate in this hollow. Pressing air in January mainly declines moving toward the South, while in July is moving toward the southeast. In relation to this, air currents are directed to these directions. Air currents during the summer and winter move from larger geographical width toward smaller ones and thereby reduce the temperature influence: Although, the character of the climate over certain areas is influenced by many factors, in this paper particular attention will be given to changes of temperature, winds, air, humidity and rainfalls. [ABSTRACT FROM AUTHOR]

Vegetated foredunes are widespread aeolian landforms along wave‐dominated sandy coasts. In contrast to previous advances in dune erosion during storm surges, there is a little empirical data and understanding of aeolian processes during foredune recovery and growth. Based on a comprehensive data set (airflow, sand transport, topography change, and vegetation cover) collected across a steep (1:2.5, 21.8°), high (20 m) foredune during a windy 5‐week period at Egmond aan Zee, the Netherlands, we demonstrate in agreement with previous studies that shore‐perpendicular winds accelerate by a factor of 3 from dune foot to crest but result in low aeolian mass fluxes that are maximum at the dunefoot, favoring local deposition. In contrast, oblique and alongshore winds up the foredune are accelerated less (or even decelerate) but are important in bringing sand from the dunefoot on to the foredune slope, where it is deposited when vegetation cover exceeds about 50% of the maximum density measured on the dune crest. Moreover, our data suggest that sediment flux at the dune foot is limited by fetch‐induced sediment availability, whereas sediment flux at the dune crest is limited by transport capacity, which depends on the wind velocity and the distance traveled over vegetation. Our study thus highlights the importance of wind direction and vegetation cover to foredune growth and recovery. Key Points: Shore‐normal winds are accelerated across a vegetated foredune slope but are accompanied by an onshore reduction in aeolian mass fluxSediment transport at the dunefoot and crest is governed by fetch and transport limitations respectivelyForedune growth and recovery is thus strongly influenced by wind direction and vegetation cover [ABSTRACT FROM AUTHOR]

By analyzing the data collected over a rice paddy field in China, the occurrence of large drag coefficient in light winds (U ≤ 1ms−1) under near‐neutral conditions (−0.1 ≤ z/L ≤ 0.1) is analyzed in this study. It is found that, with the use of either vector‐ or scalar‐averaged wind speed, the drag coefficient under near‐neutral conditions (CDN) always increases with the decrease of wind speed. Such behavior of CDN cannot be interpreted by the change of aerodynamic roughness length z0 because it would need to be enlarged by an order of magnitude. While in light winds, the nonlocal transport, which is caused by large‐scale eddies and overlooked by traditional Monin‐Obukhov Similarity theory, is found to be the main cause of increased CDN. At last, a fixing term related to nonlocal effects is proposed based on our observation, and its applicability is verified with two AmeriFlux observation sites with a landscape of forest and savanna, respectively. Plain Language Summary: According to the Monin‐Obukhov Similarity (MOS) theory, the drag coefficient over land under near‐neutral conditions (CDN) should be a constant and independent of wind speed because of the static surface roughness elements. However, the abnormal increase of CDN in light winds has been reported in many observations. In this study, we first examine the characteristics and mechanisms of the increased CDN in light winds. We conclude that the nonlocal transport caused by large‐scale eddies is the major cause for the increased CDN in light winds. Furthermore, to successfully predict the variation of CDN with wind speed within MOS framework, we propose a fixing term related to nonlocal effects with our rice paddy observations, and the applicability of this fixing term is verified by two AmeriFlux observation sites with a landscape of forest and savanna, respectively. Key Points: The increase of drag coefficient under near‐neutral conditions (CDN) with the decrease of wind speed in light winds is observedThe nonlocal transport caused by large‐scale eddies in light winds is found as the main cause of the associated large CDNA fixing term related to nonlocal effects to improve the calculation of CDN is proposed and verified [ABSTRACT FROM AUTHOR]

Estuaries are productive ecosystems that support extensive vertebrate and invertebrate communities, but some have suffered from an accelerated pace of acidification in their bottom waters. A major challenge in the study of estuarine acidification is strong temporal and spatial variability of carbonate chemistry resulting from a wide array of physical forces such as winds, tides and river flows. Most past studies of carbonate system dynamics were limited to the along channel direction, while lateral dynamics received less attention. Recent observations in Chesapeake Bay showed strong lateral asymmetry in the partial pressure of carbon dioxide (pCO2) and air-sea CO2 flux during a single wind event, but comparable responses to different wind events has yet to be investigated. In this work, a coupled hydrodynamic-carbonate chemistry model is used to understand wind-driven variability in the estuarine carbonate system. It is found that wind-driven lateral upwelling ventilates high DIC (Dissolved Inorganic Carbon) and CO2 deep water and raises surface pCO2, thereby modifying the air-sea CO2 flux. The upwelling also advects low pH water onto the adjacent shoals and reduces the aragonite saturation state Ωarag in these shallow water environments, producing large temporal pH fluctuations and low pH events. Regime diagrams are constructed to summarize the effects of wind events on temporal pH and Ωarag fluctuations and the lateral gradients in DIC, pH, and pCO2 in the estuary. This modeling study provides a mechanistic explanation for the observed wind-driven lateral variability in DIC and pCO2 and reproduces large pH and Ωarag fluctuations that could be driven by physical forcing. Given that current and historic mainstem Bay oyster beds are located in shallow shoals affected by this upwelling, a large fraction of the oyster beds (100–300 km2) could be exposed to carbonate mineral under-saturated (Ω

This software assimilates data from an arbitrary number of weather radars together with other spatial wind fields (eg numerical weather forecasting model data) in order to retrieve high resolution three dimensional wind fields. PyDDA uses NumPy and SciPy’s optimization techniques combined with the Python Atmospheric Radiation Measurement (ARM) Radar Toolkit (Py-ART) in order to create wind fields using the 3D variational technique (3DVAR). PyDDA is hosted and distributed on GitHub at https://github.com/openradar/PyDDA. PyDDA has the potential to be used by the atmospheric science community to develop high resolution wind retrievals from radar networks. These retrievals can be used for the evaluation of numerical weather forecasting models and plume modelling. This paper shows how wind fields from 2 NEXt generation RADar (NEXRAD) WSR-88D radars and the High Resolution Rapid Refresh can be assimilated together using PyDDA to create a high resolution wind field inside Hurricane Florence. Funding statement: The development of this software is supported by the Climate Model Development and Validation (CMDV) activity which is funded by the Office of Biological and Environmental Research in the US Department of Energy Office of Science.

The role of storm events in controlling chlorophyll distribution along the oligotrophic Rottnest continental shelf is examined data collected by autonomous ocean gliders combined with meteorological data. Spatial and temporal distribution of chlorophyll concentrations were obtained from a repeated transect across the shallow continental shelf that revealed complex relationships among wind events (e.g., differences in wind speed and direction) and chlorophyll concentrations. Data indicated that the water column responded rapidly to changes in wind speeds alternating between stratification, de-stratification and vice-versa over 1–3 days. Under low wind conditions (wind speeds < 7 ms–1), the water column was stratified and dense shelf water cascades (DSWC) was the dominant feature. The majority of DSWC events were associated with synchronous increases in chlorophyll and suspended sediment, often close to the seabed. During storm events (wind speeds > 15 ms–1) higher chlorophyll values were present throughout the vertically mixed water column. Maximum chlorophyll concentrations, more than double that due to climatology, were observed 1–3 days after the passage of storms subsequent to sediment re-suspension. Storm events, with an onshore component, promoted downwelling, the water column retained vertical stratification, and DSWC was present across the shelf. Here, DSWC intensified with higher chlorophyll in the cascaded water extending further offshore. It is concluded that wind speed and direction are the dominant parameters controlling the distribution of chlorophyll particularly during storm events.

Abstract We compare hourly averaged neutral winds derived from two meteor radars operating at 33.2 and 55 MHz to estimate the errors in these measurements. We then compare the meteor radar winds with those from a medium-frequency partial reflection radar operating at 1.94 MHz. These three radars are located at Davis Station, Antarctica. We then consider a middle-latitude 55 MHz meteor radar wind comparison with a 1.98 MHz medium-frequency partial reflection radar to determine how representative the Davis results are. At both sites, the medium-frequency radar winds are clearly underestimated, and the underestimation increases from 80 km to the maximum height of 98 km. Correction factors are suggested for these results.

During the months of June to September 2021, several warm episodes and heatwaves were recorded in the Canary Islands. These episodes are due to the disruption of the northeast flow and the arrival of Saharan air masses. The article analyzes the evolution of temperatures and warm episodes in the Canary Islands from 1974 to 2020, concluding that there has been an increase in the number of days with maximum temperatures above 30 °C per decade. A secondary peak in March is also observed in some stations, possibly related to Saharan dust intrusions. In addition, increasing trends were found in monthly average temperatures, being more pronounced in April, May, and October. [Extracted from the article]

The Aeolus mission objectives are to improve numerical weather prediction (NWP) and enhance the understanding and modeling of atmospheric dynamics on global and regional scale. Given the first successes of Aeolus in NWP, it is time to look forward to future vertical wind profiling capability to fulfill the rolling requirements in operational meteorology. Requirements for wind profiles and information on vertical wind shear are constantly evolving. The need for high-quality wind and profile information to capture and initialize small-amplitude, fast-evolving, and mesoscale dynamical structures increases, as the resolution of global NWP improved well into the 3D turbulence regime on horizontal scales smaller than 500 km. In addition, advanced requirements to describe the transport and dispersion of atmospheric constituents and better depict the circulation on climate scales are well recognized. Direct wind profile observations over the oceans, tropics, and Southern Hemisphere are not provided by the current global observing system. Looking to the future, most other wind observation techniques rely on cloud or regions of water vapor and are necessarily restricted in coverage. Therefore, after its full demonstration, an operational Aeolus-like follow-on mission obtaining globally distributed wind profiles in clear air by exploiting molecular scattering remains unique. [ABSTRACT FROM AUTHOR]

Coastal winds in the California Current System (CCS) are credited with the high productivity of its planktonic ecosystem and the shallow hypoxic and corrosive waters that structure diverse macrofaunal habitats. These winds thus are considered a leading mediator of climate change impacts in the CCS and other Eastern Boundary Upwelling systems. We use an eddy‐permitting regional model to downscale the response of the CCS to three of the major distinct climate changes commonly projected by global Earth System Models: regional winds, ocean warming and stratification, and remote water chemical properties. An increase in alongshore winds intensifies spring upwelling across the CCS, but this response is muted by increased stratification, especially during summer. Despite the seasonal shift in regional wind‐driven upwelling, basin‐scale changes are the decisive factor in the response of marine ecosystem properties including temperature, nutrients, productivity, and oxygen. Downscaled temperature increases and dissolved oxygen decreases are broadly consistent with coarse resolution Earth System Models, and these projected changes are large and well constrained across the models, whereas nutrient and productivity changes are small compared to the intermodel spread. These results imply that global models with poor resolution of coastal processes nevertheless yield important information about the dominant climate impacts on coastal ecosystems. Key Points: We dynamically downscale the response of the California Current System to climate changes from five global Earth System ModelsStratification and remote chemical properties, rather than regional winds, play a decisive role in coastal biogeochemistry changesOxygen decreases and temperature increases are robust across downscaled models, but the nutrient and productivity changes are not [ABSTRACT FROM AUTHOR]

The article talks about the conditions of monsoon and the weather of Spain in July 2020. It mentions about the high frequency of the east winds in the Peninsula; and the presence of an anomaly positive temperature at high levels of the troposphere. It also mentions that the language of negative pressure anomaly has extended from the islands of Cape Verde to the southwest of the Peninsula.

It is well attested that Francis Bacon considered his History of Winds to be an exemplar, but what lessons should be taken from its example have been subject to debate. Instead of looking at this work as a mere model for the fusion of natural history and natural philosophy, it is also possible to see Bacon as trying to provide tentative solutions to outstanding questions regarding the wind, a topic that was deeply scrutinized during the early modern period. An examination of Bacon's provisional concluding rules reveals deep correspondences with earlier works, such as José de Acosta's Natural and Moral History of the Indies, that revised classical understandings of the wind based on experience, experiments, and accounts of travels beyond Europe. Understanding the History of Winds as a genuine attempt to solve outstanding questions about the wind uncovers its debt to earlier traditions, including those related to Renaissance natural history, and shows it's influence in relation to specific theories of the wind beyond its call for methodological reform. [ABSTRACT FROM AUTHOR]