[1]ZHANG Hanbo,XU Yong,DOU Shiqing,et al.TRMM Downscaling Data of Yangtze Based on GWR Model[J].Research of Soil and Water Conservation,2021,28(03):149-155.
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Research of Soil and Water Conservation[ISSN 1005-3409/CN 61-1272/P] Volume:
28
Number of periods:
2021 03
Page number:
149-155
Column:
Public date:
2021-04-20
- Title:
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TRMM Downscaling Data of Yangtze Based on GWR Model
- Author(s):
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ZHANG Hanbo1, XU Yong1, DOU Shiqing1, JING Juanli1, ZHANG Nan1, ZHANG Weidong2
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(1.College of Geomatics and Geoinformation, Guilin University of Technology Guilin, Guangxi 541006, China; 2.Heilongjiang Academy of Agricultural Reclamation, Harbin 150038, China)
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- Keywords:
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TRMM 3B43; GWR; scale down; vegetation index; Yangtze River Basin
- CLC:
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P426.6
- DOI:
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- Abstract:
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Remote sensing precipitation data is widely used, but its spatial resolution fails to meet the regional spatial accuracy requirements. Based on the Tropical Rainfall Measuring Mission(TRMM)precipitation product TRMM 3B43 from 2001 to 2019, combining with the digital elevation model(DEM), enhanced vegetation index(EVI), normalized difference vegetation index(NDVI), and aspect data, a geographically weighted regression model(GWR)was construct. The current mainstream vegetation indices(NDVI, EVI)were selected as explanatory variables to downscale the TRMM data of the Yangtze River Basin. We verified the accuracies of the TRMM data before and after downscaling based on the observation values of 147 meteorological stations located in the study area. The results showed that:(1)the TRMM data and in situ observation data showed good consistency and applicability in space and time; the correlation coefficient of each station ranged from 0.46 to 0.97;(2)the spatial resolution of downscaling data was greatly improved(from 0.25° to 1 km)under the premise of ensuring the accuracy of the data; the NDVI downscaling TRMM data were better than the EVI downscaling TRMM data, which could more truthfully reflect the characteristics of precipitation in the study area;(3)compared with the original TRMM data, the precipitation range of the downscaling data was extended; the downscaling results of precipitation of wet years were better than those of dry years. Downscaling TRMM data are of great importance to advance the research on the temporal and spatial variability of regional precipitation, which has the certain research significance.