Search

Your search keyword '"You, Yalei"' showing total 47 results
Start Over Author "You, Yalei"
47 results on '"You, Yalei"'

7. Predicting Land Cover Using a GIS-Based Markov Chain and Sea Level Inundation for a Coastal Area.

Author

Healey, Colleen, Ghoneim, Eman, Loh, Ai Ning, and You, Yalei

Subjects
LAND cover, BEACHES, SEA level, MARKOV processes, LAND use, BARRIER islands
Abstract

New Hanover County, North Carolina, has been experiencing rapid population growth and is expected to continue this growth, leading to increased land use and development in the area. The county is also threatened by sea level rise (SLR) and its effects because of its coastal location and frequent occurrences of major storms and hurricanes. This study used a land change modeler to map the land cover change throughout the county over a period of 20 years, and predicted land cover distribution in the area in the years 2030 and 2050. Statistics revealed that the developed land in the area increased by 85 km2 between 2000 and 2010, and by 60 km2 between 2010 and 2020. Such land is predicted to increase by another 73 km2 by 2030, and 63 km2 by 2050. This increase in development is expected to occur mainly in the central area of the county and along the barrier islands. Modeling of SLR illustrated that the northwestern part of New Hanover County along the Cape Fear River, as well as the beach towns located on the barrier islands, are estimated be the most affected locations. Results indicate that sections of major highways throughout the county, including I-140 near downtown Wilmington and US-421 in Carolina Beach, may be inundated by SLR, which might delay residents during mandatory evacuations for emergency situations such as hurricanes. Some routes may be unusable, leading to traffic congestion on other routes, which may impede some residents from reaching safety before the emergency. Wrightsville Beach and Carolina Beach are estimated to have the highest levels of inundation, with 71.17% and 40.58% of their land being inundated under the most extreme SLR scenario of 3 m, respectively. The use of the present research approach may provide a practical, quick, and low-cost method in modeling rapidly growing urban areas along the eastern United States coastline and locating areas at potential risk of future SLR inundation. [ABSTRACT FROM AUTHOR]

Published
2024
Full Text
View/download PDF

11. A Community Error Inventory for Satellite Microwave Observation Error Representation and Uncertainty Quantification.

Author

Xun Yang, John, You, Yalei, Blackwell, William, Cheng Da, Kalnay, Eugenia, Grassotti, Christopher, Quanhua (Mark) Liu, Ferraro, Ralph, Huan Meng, Cheng-Zhi Zou, Shu-Peng Ho, Jifu Yin, Petkovic, Veljko, Hewison, Timothy, Posselt, Derek, Gambacorta, Antonia, Draper, David, Misra, Sidharth, Kroodsma, Rachael, and Min Chen

Subjects
*ERRORS-in-variables models, *MICROSPACECRAFT, *MICROWAVES, *INVENTORIES, *NUMERICAL weather forecasting
Abstract

Satellite observations are indispensable for weather forecasting, climate change monitoring, and environmental studies. Understanding and quantifying errors and uncertainties associated with satellite observations are essential for hardware calibration, data assimilation, and developing environmental and climate data records. Satellite observation errors can be classified into four categories: measurement, observation operator, representativeness, and preprocessing errors. Current methods for diagnosing observation errors still yield large uncertainties due to these complex errors. When simulating satellite errors, empirical errors are usually used, which do not always accurately represent the truth. We address these challenges by developing an error inventory simulator, the Satellite Error Representation and Realization (SatERR). SatERR can simulate a wide range of observation errors, from instrument measurement errors to model assimilation errors. Most of these errors are based on physical models, including existing and newly developed algorithms. SatERR takes a bottom-up approach: errors are generated from root sources and forward propagate through radiance and science products. This is different from, but complementary to, the top-down approach of current diagnostics, which inversely solves unknown errors. The impact of different errors can be quantified and partitioned, and a ground-truth testbed can be produced to test and refine diagnostic methods. SatERR is a community error inventory, open-source on GitHub, which can be expanded and refined with input from engineers, scientists, and modelers. This debut version of SatERR is centered on microwave sensors, covering traditional large satellites and small satellites operated by NOAA, NASA, and EUMETSAT. [ABSTRACT FROM AUTHOR]

Published
2024
Full Text
View/download PDF

12. Enhancing GPM Passive and Combined Microwave Algorithms with Dynamic Surface Information for Drizzle Retrieval and Improved Precipitation Detection Over Land

Author

Ringerud, Sarah, Munchak, Joe, Peters-Lidard, Christa, and You, Yalei

Subjects
Earth Resources And Remote Sensing
Abstract

Following the 2014 launch of the Global Precipitation Measurement Mission (GPM), an unprecedented combination of coincident active and passive microwave observations are available for state of the art precipitation retrieval. The GPM Combined Algorithm forms the backbone of this effort, optimizing geophysical variables for agreement with the full suite of multi-spectral information content. These combined retrievals are then utilized, along with a radiative transfer model, as a database applied for retrievals across a constellation of passive microwave radiometers of varying frequencies. By keeping such retrievals related through the transfer standard of the combined algorithm, level 3 products such as the Integrated Multi-satellitE Retrievals for GPM (IMERG) are able to provide consistent global products for users at the higher temporal resolution required for hydrological applications. In initial versions of the combined product, precipitation retrievals are carried out only in the presence of a signal from the active radar. As a result, light precipitation and drizzle below the threshold of DPR sensitivity are not included in any of the products down the chain from the constellation to IMERG. In this work, the effects of enhancing the retrievals with a surface emissivity and non-raining water vapor retrieval using the passive observations are explored. Over both ocean and land, the surface retrieval is used to identify areas with high probability of light precipitation and drizzle which is then quantified using techniques derived from the higher sensitivity CloudSat mission. Results indicate successful inclusion of drizzle in the retrievals that can then be included in the constellation databases, as well as improvement in passive microwave false positive precipitation signals over land in cases where surface scattering was misinterpreted as precipitation signal. The inclusion of the dynamic surface information also creates a more robust, radiometrically consistent retrieval scheme for process studies and hydrologic applications.

Published
2019

13. SatERR: A Community Error Inventory for Satellite Microwave Observation Error Representation and Uncertainty Quantification

Author

Yang, John Xun, primary, You, Yalei, additional, Blackwell, William, additional, Da, Cheng, additional, Kalnay, Eugenia, additional, Grassotti, Christopher, additional, Liu, Quanhua (Mark), additional, Ferraro, Ralph, additional, Meng, Huan, additional, Zou, Cheng-Zhi, additional, Ho, Shu-Peng, additional, Yin, Jifu, additional, Petkovic, Veljko, additional, Hewison, Timothy, additional, Posselt, Derek, additional, Gambacorta, Antonia, additional, Draper, David, additional, Misra, Sidharth, additional, Kroodsma, Rachael, additional, and Chen, Min, additional

Published
2023
Full Text
View/download PDF

19. Impact of Microwave Sounder (and Imager) Calibration on Precipitation for the Global Precipitation Measurement (GPM) Mission

Author

Kroodsma, Rachael and You, Yalei

Subjects
Earth Resources And Remote Sensing
Abstract

Cross-track microwave sounders make up a significant percentage of the radiometers included in the Global Precipitation Measurement (GPM) constellation. Therefore, it is important to properly assess the calibration of each sounder instrument and to understand the impact of the calibration on the derived precipitation rates. This ensures an accurate precipitation product is produced for the entire constellation. This paper will use data from past and current microwave sounders to show how offsets in the calibration can impact the precipitation using the GPM Level 2 GPROF algorithm. Potential improvements to the instrument calibration will be assessed by analyzing how they would positively impact the precipitation trends and agreement among the constellation sensors.

Published
2019

31. Extreme Lake-Effect Snow from a GPM Microwave Imager Perspective: Observational Analysis and Precipitation Retrieval Evaluation

Author

Milani, Lisa, primary, Kulie, Mark S., additional, Casella, Daniele, additional, Kirstetter, Pierre E., additional, Panegrossi, Giulia, additional, Petkovic, Veljko, additional, Ringerud, Sarah E., additional, Rysman, Jean-François, additional, Sanò, Paolo, additional, Wang, Nai-Yu, additional, You, Yalei, additional, and Skofronick-Jackson, Gail, additional

Published
2021
Full Text
View/download PDF

34. Raindrop Signature from Microwave Radiometer Over Deserts

Author

You, Yalei, primary, Joseph Munchak, S., additional, Ferraro, Ralph, additional, Mohr, Karen, additional, Peters‐Lidard, Christa, additional, Prigent, Catherine, additional, Ringerud, Sarah, additional, Rudlosky, Scott, additional, Wang, Heshun, additional, Norouzi, Hamidreza, additional, and Prakash, Satya, additional

Published
2020
Full Text
View/download PDF

41. Applicability of cumulus convective parameter schemes in RegCM3 to the rainfall over the Longitudinal Range-Gorge Region

Author

Cao Jie, Zhang XiuNian, Yang Ruo-wen, and You YaLei

Subjects
Convection, Multidisciplinary, Climatology, Range (statistics), Environmental science, Climate simulation
Abstract

To test the applicability of cumulus convective parameter schemes in RegCM3 to the rainfall over the Longitudinal Range-Gorge Region (LRGR), the May and the summer rainfalls from 1982 to 2001 were simulated with different cumulus convective parameter schemes in RegCM3. The results of quantitative analysis contrasting simulation rainfall with observational one indicate that Fritsch-Chappell cumulus convective parameter scheme has the best simulation ability to the 20-year total May rainfall over LRGR, and the simulation ability of Anthes-Kuo cumulus convective parameter scheme takes the second place. Anthes-Kuo cumulus convective parameter scheme has the best simulation ability to the 20-year total summer rainfall over LRGR, and the simulation ability of Fritsch-Chappell gets the second place. The total rainfall simulated over LRGR is less than the observational one. The result of simulating interannual variation of May and summer rainfalls over LRGR is almost the same as that of simulating 20-year total rainfall. The Anthes-Kuo and the Fritsch-Chappell cumulus convective parameter schemes adapt to describing cumulus convective process in May and summer over LRGR.

Published
2007

Catalog

Books, media, physical & digital resources
See catalog results