RAIN_CHANG: Monthly Oceanic Rainfall Indices from SSM/I Satellites, 1987-1995

RAIN_CHANG is an early Global Precipitation Climatology Project product providing monthly rainfall indices over oceans derived from Special Sensor Microwave Imager data from DMSP satellites F8 and F11. The dataset covers the period from July 1987 to December 1995 on a 5-degree by 5-degree grid from 50°N to 50°S. It was developed by NASA to support long-term climate research for EOS global change and GEWEX-related studies.

Use Cases

• Analyzing long-term monthly rainfall trends over oceans based on the 1987-1995 time range
• Comparing early satellite-derived precipitation estimates with newer products like GPCP based on the SSM/I source
• Studying spatial rainfall distribution on a 5-degree grid between 50°N and 50°S
• Investigating the impact of beam filling error corrections on rainfall estimates based on the described equation

Strengths

• Provides a continuous 8.5-year time series from July 1987 to December 1995
• Data is spatially gridded at a 5-degree resolution covering a 72 x 20 grid from 50°N to 50°S
• Includes quality flags for land pixels, island contamination, and non-convergent retrievals set to -10.0

Limitations

• Description metadata is limited; actual data quality requires manual inspection after download
• The dataset is an early product with recommended replacements (GPCP, GPROF), suggesting it may be superseded
• Valid values are only over ocean areas, with land and island pixels flagged out

Provenance

Source

National Aeronautics and Space Administration

Collection Method

Derived from Special Sensor Microwave Imager data using the Wilheit, Chang and Chiu (1991) method

Time Range

July 1987 to December 1995

Freshness

Last updated 2026-03-13 03:45:28.945558; freshness should be verified

Geography

Global oceans from 50°N to 50°S