Improved Observation of Global Precipitation During the Satellite Era
Abstract
The development of global precipitation information is described moving from the pre-satellite era, through the first large-scale satellite estimates over ocean in the 1970s and 1980s into the use of routine passive microwave and IR observations in the 1990s and the development the modern system of global estimation with TRMM, GPM and CloudSat.
Intermittent, quasi-global ocean estimates began in the 1970s and 1980s and became somewhat routine in the early 1990s, with the beginning of SSM/I in 1987. This also led to an explosion of passive microwave algorithms, for both ocean and land backgrounds, and the merging of passive microwave and infrared-based estimates, along with raingauge analysis over land, to provide global monthly estimates, such as from the Global Precipitation Climatology Project (GPCP). In 1986 the space agencies of the U.S. and Japan initiated a joint research and development effort to accurately estimate tropical rainfall using both passive microwave and radar observations resulting in the Tropical Rainfall Measuring Mission (TRMM), flown from 1997-2014 followed by the Global Precipitation Measurement (GPM) mission (2014-present) continuing and expanding (both in latitude and sensor wavelengths) the observations. TRMM and GPM, along with CloudSat, with its higher frequency radar, form the core of the current, modern system of global precipitation observations. Results from these three missions will be compared to GPCP to understand how the new information will modify our knowledge of the long-term record. The development of fine time resolution (a day or less) global information during the TRMM/GPM period, and its impact on research and applications, will also be described. Despite these advances, there is still significant room for improvement, including in the accuracy of both mean and extreme precipitation values and in differences between the radar and passive microwave observations. In addition, high latitude and cold season retrievals are still problematic and the fine-time resolution products must be used cautiously because of inhomogeneities and other issues. However, the progress during the past decades has already led to expansive new knowledge of our climate and the global water cycle, improved daily monitoring and applications and a position from which to continue to advance.- Publication:
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AGU Fall Meeting Abstracts
- Pub Date:
- December 2019
- Bibcode:
- 2019AGUFM.H21E..01A
- Keywords:
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- 3354 Precipitation;
- ATMOSPHERIC PROCESSES;
- 3360 Remote sensing;
- ATMOSPHERIC PROCESSES;
- 1655 Water cycles;
- GLOBAL CHANGE;
- 1840 Hydrometeorology;
- HYDROLOGY