In:
Earth System Science Data, Copernicus GmbH, Vol. 12, No. 3 ( 2020-07-08), p. 1525-1544
Abstract:
Abstract. Precipitation estimates with fine quality and spatio-temporal resolutions
play significant roles in understanding the global and regional cycles of
water, carbon, and energy. Satellite-based precipitation products are capable
of detecting spatial patterns and temporal variations of precipitation at
fine resolutions, which is particularly useful over poorly gauged regions.
However, satellite-based precipitation products are the indirect estimates
of precipitation, inherently containing regional and seasonal systematic
biases and random errors. In this study, focusing on the potential drawbacks
in generating Integrated Multi-satellitE Retrievals for Global Precipitation
Measurement (IMERG) and its recently updated retrospective IMERG in the
Tropical Rainfall Measuring Mission (TRMM) era (finished in July 2019),
which were only calibrated at a monthly scale using ground observations,
Global Precipitation Climatology Centre (GPCC, 1.0∘/monthly), we
aim to propose a new calibration algorithm for IMERG at a daily scale and to
provide a new AIMERG precipitation dataset (0.1∘/half-hourly,
2000–2015, Asia) with better quality, calibrated by Asian Precipitation – Highly Resolved Observational Data Integration Towards Evaluation of Water Resources (APHRODITE, 0.25∘/daily) at the daily scale for the Asian applications. The main
conclusions include but are not limited to the following: (1) the proposed daily calibration
algorithm (Daily Spatio-Temporal Disaggregation Calibration Algorithm,
DSTDCA) is effective in considering the advantages from both satellite-based
precipitation estimates and the ground observations; (2) AIMERG performs
better than IMERG at different spatio-temporal scales, in terms of both
systematic biases and random errors, over mainland China; and (3) APHRODITE demonstrates significant advantages compared to GPCC in calibrating IMERG, especially over mountainous regions with complex terrain, e.g.
the Tibetan Plateau. Additionally, results of this study suggest that it is
a promising and applicable daily calibration algorithm for GPM in generating
the future IMERG in either an operational scheme or a retrospective manner. The
AIMERG data are freely accessible at https://doi.org/10.5281/zenodo.3609352 (for the period from 2000 to 2008)
(Ma et al., 2020a) and https://doi.org/10.5281/zenodo.3609507
(for the period from 2009 to 2015) (Ma et al., 2020b). Highlights. A new effective daily calibration approach, DSTDCA, for improving the GPM-era IMERG is provided. New AIMERG precipitation data (0.1∘/half-hourly, 2000–2015,
Asia) are provided. Bias of AIMERG is significantly improved compared with that of IMERG. APHRODITE is more suitable than GPCC in anchoring IMERG over Asia.
Type of Medium:
Online Resource
ISSN:
1866-3516
DOI:
10.5194/essd-12-1525-2020
Language:
English
Publisher:
Copernicus GmbH
Publication Date:
2020
detail.hit.zdb_id:
2475469-9
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