Dataset Information

Global daily 1 km land surface precipitation based on cloud cover-informed downscaling.

ABSTRACT: High-resolution climatic data are essential to many questions and applications in environmental research and ecology. Here we develop and implement a new semi-mechanistic downscaling approach for daily precipitation estimate that incorporates high resolution (30 arcsec, ≈1 km) satellite-derived cloud frequency. The downscaling algorithm incorporates orographic predictors such as wind fields, valley exposition, and boundary layer height, with a subsequent bias correction. We apply the method to the ERA5 precipitation archive and MODIS monthly cloud cover frequency to develop a daily gridded precipitation time series in 1 km resolution for the years 2003 onward. Comparison of the predictions with existing gridded products and station data from the Global Historical Climate Network indicates an improvement in the spatio-temporal performance of the downscaled data in predicting precipitation. Regional scrutiny of the cloud cover correction from the continental United States further indicates that CHELSA-EarthEnv performs well in comparison to other precipitation products. The CHELSA-EarthEnv daily precipitation product improves the temporal accuracy compared with a large improvement in the spatial accuracy especially in complex terrain.

SUBMITTER: Karger DN

PROVIDER: S-EPMC8626457 | biostudies-literature | 2021 Nov

REPOSITORIES: biostudies-literature

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Global daily 1 km land surface precipitation based on cloud cover-informed downscaling.

Karger Dirk Nikolaus DN Wilson Adam M AM Mahony Colin C Zimmermann Niklaus E NE Jetz Walter W

Scientific data 20211126 1

High-resolution climatic data are essential to many questions and applications in environmental research and ecology. Here we develop and implement a new semi-mechanistic downscaling approach for daily precipitation estimate that incorporates high resolution (30 arcsec, ≈1 km) satellite-derived cloud frequency. The downscaling algorithm incorporates orographic predictors such as wind fields, valley exposition, and boundary layer height, with a subsequent bias correction. We apply the method to t ...[more]

PMID: 34836980

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Dataset Information

Global daily 1 km land surface precipitation based on cloud cover-informed downscaling.

Publications

Global daily 1 km land surface precipitation based on cloud cover-informed downscaling.

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