HR: 1340h
AN: H33C-0479    [Abstracts]
TI: Rainfall Variability Studies Based on a Long Term Radar-Rainfall Data Set
AU: * Nelson, B R
EM: brian.nelson@noaa.gov
AF: National Research Council NOAA/NESDIS/NCDC, 151 Patton Ave, Asheville, ND 28801
AU: Bates, J J
EM: john.j.bates@noaa.gov
AF: National Climatic Data Center NOAA/NESDIS, 151 Patton Ave, Asheville, NC 28801
AB: A radar rainfall climatology has been developed based on approximately 10 years of NEXRAD level III data for several radars in the Carolina region of the southeast U.S. We are using this radar rainfall climatology to investigate the variability and trends of precipitation patterns based on the high resoution radar rainfall data. The data set is provided at hourly 4x4 km2 resolution and will be integrated to daily, monthly, seasonal, and annual temporal scales. Several issues have arisen during the development of the radar rainfall climatology related to inherent biases in the radar rainfall estimates, and several steps have been taken to reduce or eliminate these biases. Image processing techniques have been applied to try and elimate bright band and anomalous propagation. The radar range extent has been reduced to eliminate the effects of range on the rainfall estimates, and radar calibration bias adjustment has been applied to smooth radar to radar bias effects. These improved rainfall estimates will be used in studies that look at the variability of rainfall in space-time domains and they will be used to determine trends of rainfall from seasonal and interannual. Further studies will be carried out to extract extreme events through data mining techniques. Extreme events are important when investigating the variability of rainfall as they help to more accurately define the overall distribution of rainfall events, and this has implications in climate prediction and weather and flood forecasting for example.
DE: 1833 Hydroclimatology
DE: 1854 Precipitation (3354)
SC: Hydrology [H]
MN: 2004 AGU Fall Meeting