Comparison of GPM and TRMM Satellite-Derived Precipitation Rates in Tropical Cyclones

The Tropical Rainfall Measuring Mission (TRMM) satellite, a joint mission between NASA and the Japan Aerospace Exploration Agency (JAXA) to study rainfall for weather and climate research, officially ended on 15 April 2015, after producing scientific data for over 17 years. The TRMM Product 3B42 (V7) (http://disc.sci.gsfc.nasa.gov/precipitation/documentation/TRMM_README/TRMM_3B42_readme.shtml), which has 0.25° horizontal grid spacing (latitude and longitude) and 3-hourly temporal frequency, has been particularly useful for estimating precipitation rate in tropical cyclones. As a replacement for TRMM, NASA and JAXA launched the Global Precipitation Measurement (GPM) Mission satellite on 27 February 2014 (http://pmm.nasa.gov/data-access/downloads/gpm). In conjunction with the launch of GPM, NASA has initiated a transition from the TRMM Product 3B42 (V7), also known as the TRMM Multi-satellite Precipitation Analysis (TMPA), to the Integrated Multi-satellitE Retrievals for GPM (IMERG) (http://pmm.nasa.gov/sites/default/files/document_files/TMPA-to-IMERG_transition.pdf), which has 0.1° horizontal grid spacing (latitude and longitude) and up to 30-minute temporal frequency since 12 March 2014. Scientists at AIR Worldwide are conducting their own comparisons between the TMPA and IMERG precipitation rate products for various landfalling tropical cyclones in order to determine whether risk analysis algorithms derived from satellite-based precipitation estimates can be applied to the IMERG data in a similar way as those algorithms were applied to the TMPA data, accounting for the differences in spatial and temporal resolution of the data.