Erich Franz Stocker

The TRMM Multisatellite Precipitation Analysis (TMPA): Quasi-Global, Multiyear, Combined-Sensor Precipitation Estimates at Fine Scales

Abstract The Tropical Rainfall Measuring Mission (TRMM) Multisatellite Precipitation Analysis (TMPA) provides a calibration-based sequential scheme for combining precipitation estimates from multiple satellites, as well as gauge analyses where feasible, at fine scales (0.25° × 0.25° and 3 hourly). TMPA is available both after and in real time, based on calibration by the TRMM Combined Instrument and TRMM Microwave Imager precipitation products, respectively. Only the after-real-time product incorporates gauge data at the present. The dataset covers the latitude band 50°N–S for the period from 1998 to the delayed present. Early validation results are as follows: the TMPA provides reasonable performance at monthly scales, although it is shown to have precipitation rate–dependent low bias due to lack of sensitivity to low precipitation rates over ocean in one of the input products [based on Advanced Microwave Sounding Unit-B (AMSU-B)]. At finer scales the TMPA is successful at approximately reproducing the s...

The Global Precipitation Measurement (GPM) Mission for Science and Society

The GPM mission collects essential rain and snow data for scientific studies and societal benefit.

NASA’s Remotely Sensed Precipitation: A Reservoir for Applications Users

AbstractPrecipitation is the fundamental source of freshwater in the water cycle. It is critical for everyone, from subsistence farmers in Africa to weather forecasters around the world, to know when, where, and how much rain and snow is falling. The Global Precipitation Measurement (GPM) Core Observatory spacecraft, launched in February 2014, has the most advanced instruments to measure precipitation from space and, together with other satellite information, provides high-quality merged data on rain and snow worldwide every 30 min. Data from GPM and the predecessor Tropical Rainfall Measuring Mission (TRMM) have been fundamental to a broad range of applications and end-user groups and are among the most widely downloaded Earth science data products across NASA. End-user applications have rapidly become an integral component in translating satellite data into actionable information and knowledge used to inform policy and enhance decision-making at local to global scales. In this article, we present NASA p...

Ground validation of TRMM and AMSU microwave precipitation estimates

Global rain gauge data were used to validate the instantaneous and 3-hourly TRMM TMI and AMSU microwave rainfall products for a two-year period from January 2001 to December 2002. In the comparison of instantaneous rainfall products, all satellite data were aggregated to a 0.1/spl deg//spl times/0.1/spl deg/ grid with gauge location at the grid center and compared to the 60-minute gauge rain. The biases against gauge rain are +15% and -20% for TMI and AMSU land/coastal rain estimates, respectively. The gauge data from ocean area in this study were only from Kwajalein, The biases as compared to the Kwajalein gauge data are +12% and +65% for TMI and AMSU ocean rain estimates respectively. The correlation is about 0.56 between TMI and gauge data and about 0.50 between AMSU and gauge data.

Gridded hourly text products: a TRMM data reduction approach

The quantity of satellite observations available for the study of global precipitation is both a blessing and a curse. The sheer volume and complexity of many of the data products makes it difficult for many researchers to use. This paper describes one approach that TRMM used to reduce the volume and complexity of data.

Advances in spatial data infrastructure, acquisition, analysis, archiving & dissemination

The authors review recent contributions to the state-of-thescience and benign proliferation of satellite remote sensing, spatial data infrastructure, near-real-time data acquisition, analysis on high performance computing platforms, sapient archiving, multi-modal dissemination and utilization for a wide array of scientific applications. The authors also address advances in Geoinformatics and its growing ubiquity, as evidenced by its inclusion as a focus area within the American Geophysical Union (AGU), European Geosciences Union (EGU), as well as by the evolution of the IEEE Geoscience and Remote Sensing Societys (GRSS) Data Archiving and Distribution Technical Committee (DAD TC).

A generalized logical format for inter-calibrated brightness temperatures for the global precipitation measurement mission

An important aspect of the GPM mission is the merging of precipitation data from multiple radiometers on different satellites. This requires that each radiometer be consistently calibrated and that each be intercalibrated with a mission reference standard. For GPM the reference standard is to be the core satellite carrying a dual frequency precipitation radar and a well calibrated conically scanning radiometer. This paper describes a common format for representing these intercalibrated brightness temperatures which will be used for all radiometer products from GPM partner satellites. The use of common formats ensures that users obtain all the required information and also facilitates the rain retrieval algorithm code preparation as it can always except to have the data that it needs for the retrieval.

GPM precipitation processing system

NASA’s Earth Science Enterprise (ESE) is changing focus from single satellite missions to measurement oriented programs. An example of this paradigm shift is the Global Precipitation Measurement (GPM) project. GPM is conceptualized as a rolling-wave of measurement possibilities all focused on the key precipitation parameter. In response to this shift to measurement programs and also integral to the ESE’s new strategy for processing and management its data, a measurement based approach is also critical for data processing system that support measurement programs like GPM. This paper provides an overview of the paradigm shift from mission to measurement. It also presents a summary of the ESE’s new strategy for its data systems. Building on this background the paper details the architectural, design and implementation aspects of the Precipitation Processing System (PPS). The PPS is an evolution of a single point system developed for the Tropical Rainfall Measurement Mission to a generic precipitation data system. The paper provides the context within which PPS will support the GPM program.

TRMM fire algorithm, product and applications

The TRMM Science Data and Information System (TSDIS) fire algorithm is a contextual approach that uses the TRMM Visible Infrared Scanner (VIRS) thermal channel brightness temperature, visible/near-infrared channel reflectance, and global land type data to retrieve fire pixels. The products include global images of daily hot spots and monthly fire counts at 0.5/spl deg//spl times/0.5/spl deg/ resolution, as well as text files that details necessary information of all fire pixels. In order to understand the variability of global land fires and their effects on the distribution of atmospheric aerosols, statistical methods were applied to the TSDIS fire products as well as the Total Ozone Mapping Spectrometer (TOMS) aerosol index products for a period of four years from January 1998 to December 2001. The statistical results showed contrast between North and South hemispheres and also inter-continental transitions in Africa and America. These analyses also identified 25-60 day intra-seasonal oscillations that were superimposed on the annual cycles of both fire and aerosol data. The intra-seasonal variability of fires showed similarity of Madden-Julian oscillation mode. The VIRS fire data were also compared with coincident TRMM rainfall data to investigate the interaction between fire and cloud.

Precipitation processing system for the global precipitation measurement mission

The Global Precipitation Measurement (GPM) mission is a major NASA initiative in establishing its programs on a “measurement-based” approach rather than the traditional “mission-based” approach. It also provides the opportunity to examine the appropriateness of precipitation measurement as a systematic measurement to support both ongoing research and applications. GPM will be an international partnership to offer an “unorthodox” constellation of satellites carrying radiometers. Each of the partner-contributed assets may have specific research objectives other than those of the GPM mission. Each partner will control the satellite they contribute. Control is distributed rather than centered in a single GPM control center. GPM facilitates an important effort to evolve to measurementbased missions. To support the research carried out in this new environment, NASA will provide a precipitation focused processing system that will be evolved to support GPM as well as other precipitation activities as required. Keywords—GPM; PPS; measurement-based; precipitation;