Science of Measuring Precipitation: Why It Matters Water cycling and the future availability of fresh water resources are immense societal concerns that impact every nation on Earth.... + Read More Why Measure Rainfall from Space? Precipitation is difficult to measure because precipitation systems tend to be somewhat random in character and also evolve very rapidly.... + Read More NASA'S TRMM Satellite: Prelude to GPM TRMM was the first satellite dedicated to rainfall measurement, and is the only satellite that carries a weather radar..... + Read More Towards An Integrated Satellite Estimate of Rainfall Scientists use a variety of techniques for measuring rain from space. Rainfall can be inferred from the temperature of cloud tops..... + Read More What is GPM Composed Of? GPM will be capable of measuring rain rates as small as a hundredth of an inch per hour to as large as 4 inches an hour...... + Read More

The GPM Precipitation-Measuring Instruments GPM's two versatile instruments include the GPM Microwave Imager (GMI), and GPM Dual Frequency Radar (DFR) .... + Read More GPM Ground Validation GPM is broader than a fleet of satellites. A ground validation, research and calibration program will be employed to ensure proper accuracy of the measurements..... + Read More GPM Data Products and the Data Processing System A globally diversified data acquisition and distribution network will serve as a resource for agriculture, public health, water resources management, aviation safety, etc. ..... + Read More GPM Science Serving Society GPM science will proviide advances in world health, homeland security, agriculture, land use change, and science education. + Read More