ABSTRACT
Floods are among the deadliest natural disasters in the world. Floods are closely associated with heavy precipitation and snowmelt. Nonetheless, precipitation data are essential for flood monitoring, modeling, assessment, and research. Traditional methods (e.g., gauges, radars) of precipitation measurement can be costly and difficult to deploy, particularly in remote and mountainous regions, resulting in sparse observations available for flood operation, research, and applications. In the past several decades, techniques for satellite-based precipitation estimates have been developed and with a constellation of satellites, spatiotemporal resolution of satellite-based precipitation products and abilities to detect light rain and snow with new sensor techniques have been greatly improved. As a result, satellite-based precipitation products are widely used in flood research and applications.
In this chapter, NASA global near-real-time and research precipitation products at the NASA Goddard Earth Sciences and Data and Information Services Center (GES DISC), including the near-real-time Integrated Multi-satellitE Retrievals for GPM (IMERG) product suite that consists of half-hourly near-real-time and research precipitation products on a 0.1 deg. x 0.1 deg. grid, are introduced. The GES DISC is home to the data archive for two major NASA satellite precipitation measurement missions (Tropical Rainfall Measuring Mission [TRMM] and Global Precipitation Measurement [GPM]) as well as other satellite missions and projects. Other global and regional precipitation and their ancillary products at the GES DISC are listed.
To facilitate data access, the GES DISC has developed user-friendly data services and a user support system, including an online visualization and analysis tool, Giovanni, for rapid product evaluation and exploration without downloading data and software. These services are described along with examples. Bias and systematic differences are common in satellite-based products, which is important to understand in flood research and applications. An example is presented to characterize systematic differences between the IMERG Early and Final products in a flooding event.
