Loading...
Please wait, while we are loading the content...
Similar Documents
Evaluation and Improvement of FY-4A AGRI Quantitative Precipitation Estimation for Summer Precipitation over Complex Topography of Western China
| Content Provider | MDPI |
|---|---|
| Author | Ren, Jing Xu, Guirong Zhang, Wengang Leng, Liang Xiao, Yanjiao Wan, Rong Wang, Junchao |
| Copyright Year | 2021 |
| Description | Satellite quantitative precipitation estimation (QPE) can make up for the insufficiency of ground observations for monitoring precipitation. Using an Advanced Geosynchronous Radiation Imager (AGRI) on the FengYun-4A (FY-4A) satellite and rain gauges (RGs) for observations in the summer of 2020. The existing QPE of the FY-4A was evaluated and found to present poor accuracy over the complex topography of Western China. Therefore, to improve the existing QPE, first, cloud classification thresholds for the FY-4A were established with the dynamic clustering method to identify convective clouds. These thresholds consist of the brightness temperatures (TBs) of FY-4A water vapor and infrared channels, and their TB difference. Then, quantitative cloud growth rate correction factors were introduced to improve the QPE of the convective-stratiform technique. This was achieved using TB hourly variation rates of long-wave infrared channel 12, which is able to characterize the evolution of clouds. Finally, the dynamic time integration method was designed to solve the inconsistent time matching between the FY-4A and RGs. Consequently, the QPE accuracy of the FY-4A was improved. Compared with the existing QPE of the FY-4A, the correlation coefficient between the improved QPE of the FY-4A and the RG hourly precipitation increased from 0.208 to 0.492, with the mean relative error and root mean squared error decreasing from −47.4% and 13.78 mm to 8.3% and 10.04 mm, respectively. However, the correlation coefficient is not sufficiently high; thus, the algorithm needs to be further studied and improved. |
| Starting Page | 4366 |
| e-ISSN | 20724292 |
| DOI | 10.3390/rs13214366 |
| Journal | Remote Sensing |
| Issue Number | 21 |
| Volume Number | 13 |
| Language | English |
| Publisher | MDPI |
| Publisher Date | 2021-10-29 |
| Access Restriction | Open |
| Subject Keyword | Remote Sensing Marine Engineering Fy-4a Satellite Quantitative Precipitation Estimation Brightness Temperature Dynamic Time Integration Method Complex Topography |
| Content Type | Text |
| Resource Type | Article |
