TRMM Ground Validation Radar Rain Rate Maps

Four primary ground validation sites in Darwin, Houston, Kwajalein, and Melbourne provide instantaneous rain rate data for satellite validation. The dataset contains cartesian-gridded rain rate maps derived from ground-based radar, rain gauges, and disdrometers, with units of mm/hr and a spatial range from 17 km to 150 km. It supports the validation of Tropical Rainfall Measuring Mission (TRMM) satellite precipitation products through quality-controlled, ground-truth measurements.

Use Cases

• Validating TRMM satellite rain rate retrievals based on ground-based radar and gauge measurements.
• Analyzing spatial patterns of precipitation at the four primary validation sites.
• Comparing drop size distribution (DSD) measurements from different instrument types (e.g., Joss-Waldvogel, Parsivel).
• Studying long-term rainfall trends using the high-quality network at NASA Wallops Flight Facility.

Strengths

• Data is quality-controlled as part of the TRMM Ground Validation effort.
• Includes measurements from a variety of instruments, including radar, rain gauges, and multiple disdrometer types.
• Provides long-term measurements from the NASA Wallops Flight Facility network.

Limitations

• Key metadata conflicts: last updated date differs significantly between platforms (2003 vs. 2026).
• Column names and dataset size (rows, file size) are not specified in any source.
• Documentation notes a potential data gotcha regarding the 'alt' and 'z_spacing' variables in the netCDF files.

Provenance

Source

University of Washington TRMM Ground Validation products, produced for NASA.

Collection Method

Data collected from ground-based radar, rain gauges, and disdrometers, then quality-controlled.

Freshness

Last updated dates conflict: one source reports 2003-12-31, another reports 2026-04-09.

Geography

Primary sites: Darwin, Australia; Houston, Texas; Kwajalein, Republic of the Marshall Islands; Melbourne, Florida. Additional site: NASA Wallops Flight Facility (WFF) and vicinity.