Improving the STARFM Fusion Method for Downscaling the SSEBOP Evapotranspiration Product from 1 km to 30 m in an Arid Area in China
Continuous evapotranspiration (ET) data with high spatial resolution are crucial for water resources management in irrigated agricultural areas in arid regions. Many global ET products are available now but with a coarse spatial resolution. Spatial-temporal fusion methods, such as the spatial and te...
Main Authors: | , , , |
---|---|
Format: | Article |
Language: | English |
Published: |
MDPI AG
2023-11-01
|
Series: | Remote Sensing |
Subjects: | |
Online Access: | https://www.mdpi.com/2072-4292/15/22/5411 |
_version_ | 1797457865406939136 |
---|---|
author | Jingjing Sun Wen Wang Xiaogang Wang Luca Brocca |
author_facet | Jingjing Sun Wen Wang Xiaogang Wang Luca Brocca |
author_sort | Jingjing Sun |
collection | DOAJ |
description | Continuous evapotranspiration (ET) data with high spatial resolution are crucial for water resources management in irrigated agricultural areas in arid regions. Many global ET products are available now but with a coarse spatial resolution. Spatial-temporal fusion methods, such as the spatial and temporal adaptive reflectance fusion model (STARFM), can help to downscale coarse spatial resolution ET products. In this paper, the STARFM model is improved by incorporating the temperature vegetation dryness index (TVDI) into the data fusion process, and we propose a spatial and temporal adaptive evapotranspiration downscaling method (STAEDM). The modified method STAEDM was applied to the 1 km SSEBOP ET product to derive a downscaled 30 m ET for irrigated agricultural fields of Northwest China. The STAEDM exhibits a significant improvement compared to the original STARFM method for downscaling SSEBOP ET on Landsat-unavailable dates, with an increase in the squared correlation coefficients (r<sup>2</sup>) from 0.68 to 0.77 and a decrease in the root mean square error (RMSE) from 10.28 mm/10 d to 8.48 mm/10 d. The ET based on the STAEDM additionally preserves more spatial details than STARFM for heterogeneous agricultural fields and can better capture the ET seasonal dynamics. The STAEDM ET can better capture the temporal variation of 10-day ET during the whole crop growing season than SSEBOP. |
first_indexed | 2024-03-09T16:28:54Z |
format | Article |
id | doaj.art-e16c3e10cbca496d8f5128352a057a96 |
institution | Directory Open Access Journal |
issn | 2072-4292 |
language | English |
last_indexed | 2024-03-09T16:28:54Z |
publishDate | 2023-11-01 |
publisher | MDPI AG |
record_format | Article |
series | Remote Sensing |
spelling | doaj.art-e16c3e10cbca496d8f5128352a057a962023-11-24T15:04:48ZengMDPI AGRemote Sensing2072-42922023-11-011522541110.3390/rs15225411Improving the STARFM Fusion Method for Downscaling the SSEBOP Evapotranspiration Product from 1 km to 30 m in an Arid Area in ChinaJingjing Sun0Wen Wang1Xiaogang Wang2Luca Brocca3State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering, Hohai University, Nanjing 210098, ChinaState Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering, Hohai University, Nanjing 210098, ChinaThe Pearl River Water Resources Research Institute, Guangzhou 510611, ChinaResearch Institute for the Geo-Hydrological Protection, National Research Council (CNR), Via Madonna Alta 126, 06128 Perugia, ItalyContinuous evapotranspiration (ET) data with high spatial resolution are crucial for water resources management in irrigated agricultural areas in arid regions. Many global ET products are available now but with a coarse spatial resolution. Spatial-temporal fusion methods, such as the spatial and temporal adaptive reflectance fusion model (STARFM), can help to downscale coarse spatial resolution ET products. In this paper, the STARFM model is improved by incorporating the temperature vegetation dryness index (TVDI) into the data fusion process, and we propose a spatial and temporal adaptive evapotranspiration downscaling method (STAEDM). The modified method STAEDM was applied to the 1 km SSEBOP ET product to derive a downscaled 30 m ET for irrigated agricultural fields of Northwest China. The STAEDM exhibits a significant improvement compared to the original STARFM method for downscaling SSEBOP ET on Landsat-unavailable dates, with an increase in the squared correlation coefficients (r<sup>2</sup>) from 0.68 to 0.77 and a decrease in the root mean square error (RMSE) from 10.28 mm/10 d to 8.48 mm/10 d. The ET based on the STAEDM additionally preserves more spatial details than STARFM for heterogeneous agricultural fields and can better capture the ET seasonal dynamics. The STAEDM ET can better capture the temporal variation of 10-day ET during the whole crop growing season than SSEBOP.https://www.mdpi.com/2072-4292/15/22/5411evapotranspirationdata fusionSTARFMdownscalingTVDISSEBOP |
spellingShingle | Jingjing Sun Wen Wang Xiaogang Wang Luca Brocca Improving the STARFM Fusion Method for Downscaling the SSEBOP Evapotranspiration Product from 1 km to 30 m in an Arid Area in China Remote Sensing evapotranspiration data fusion STARFM downscaling TVDI SSEBOP |
title | Improving the STARFM Fusion Method for Downscaling the SSEBOP Evapotranspiration Product from 1 km to 30 m in an Arid Area in China |
title_full | Improving the STARFM Fusion Method for Downscaling the SSEBOP Evapotranspiration Product from 1 km to 30 m in an Arid Area in China |
title_fullStr | Improving the STARFM Fusion Method for Downscaling the SSEBOP Evapotranspiration Product from 1 km to 30 m in an Arid Area in China |
title_full_unstemmed | Improving the STARFM Fusion Method for Downscaling the SSEBOP Evapotranspiration Product from 1 km to 30 m in an Arid Area in China |
title_short | Improving the STARFM Fusion Method for Downscaling the SSEBOP Evapotranspiration Product from 1 km to 30 m in an Arid Area in China |
title_sort | improving the starfm fusion method for downscaling the ssebop evapotranspiration product from 1 km to 30 m in an arid area in china |
topic | evapotranspiration data fusion STARFM downscaling TVDI SSEBOP |
url | https://www.mdpi.com/2072-4292/15/22/5411 |
work_keys_str_mv | AT jingjingsun improvingthestarfmfusionmethodfordownscalingthessebopevapotranspirationproductfrom1kmto30minanaridareainchina AT wenwang improvingthestarfmfusionmethodfordownscalingthessebopevapotranspirationproductfrom1kmto30minanaridareainchina AT xiaogangwang improvingthestarfmfusionmethodfordownscalingthessebopevapotranspirationproductfrom1kmto30minanaridareainchina AT lucabrocca improvingthestarfmfusionmethodfordownscalingthessebopevapotranspirationproductfrom1kmto30minanaridareainchina |