8.2
TRMM Ground Validation at Melbourne, Florida: 1999-2007
David B. Wolff, NASA/GSFC and SSAI, Greenbelt, MD; and B. Fisher, J. Wang, and A. Tokay
NASA's Tropical Rainfall Measuring Mission (TRMM) is a joint U.S. – Japan program. The TRMM satellite was launched in November 1997, and was originally planned as a three-year mission; however, the satellite has continued to provide high quality rain rate estimates for the global tropics to this day, and operations are currently envisaged through 2012. A major component of TRMM is its Ground Validation (GV) program. Both the GV and satellite-retrieved rain estimates have shown a convergence at key GV sites, lending credibility to the global TRMM estimates. To be sure, there are some regional differences between the various satellite estimates themselves that need to be addressed; however, TRMM is providing a high-quality, long-term climatological data set that provides rain intensity errors on the order of 10-20%, rather than pre-TRMM-era error estimates on the order of 50-100%.
Central Florida (MELB) was selected as one of four primary sites for TRMM GV operations, and is well complemented by several state-operated gauge networks, as well as a NASA-operated network at NASA Kennedy Space Center (KSC). More recently, with the participation of the University of Central Florida, two Joss-Waldvogel disdrometers have been sited near the radar, which are providing near-real-time estimates of the drop size distributions of precipitation. The principal radar is located on the eastern Atlantic seaboard in Melbourne, Florida. The area observed by the radar is approximately 50% ocean and 50% land. Florida is a sub-tropical location that receives about 70% of its annual rainfall between June and September. Most of this rainfall is due to sea breeze induced isolated convective systems, and more organized tropical systems. Florida's annual rainfall budget also receives a contribution from mid-latitude synoptic systems during northern hemispheric winter months when frontal boundaries occasionally affect the area. The diurnal cycle of rainfall at MELB is dominated by the frequent occurrence of sea breeze induced convection in the mid-to-late afternoon. This study will use the near decade-long record of observations to provide a climatology of precipitation over central Florida over daily, monthly, seasonal, and yearly scales, including the following: rain rate distributions, drop size distribution characteristics, reflectivity distributions. A discussion of the various statistics during passage of easterly wave, tropical storms, and hurricanes will also be provided.
Recorded presentationSession 8, Validation of Hydrometeorological Observations, Part II
Wednesday, 23 January 2008, 10:30 AM-12:00 PM, 223
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