2012 AGU Chapman Conference on Remote Sensing of the ...

ABSTRACTSlisted by name of presenterAdachi, AhoroRainfall estimation and detection of hazardousconvective cells with a dual-polarized C-band radarAdachi, Ahoro 1 ; Kobayashi, Takahisa 1 ; Yamauchi, Hiroshi 1 ;Onogi, Shigeru 21. Meteorological Satellite and Observation SystemDepartment, Meteorological Research Institute, Tsukuba,Japan2. Physical Meteorology Department, MeteorologicalResearch Institute, Tsukuba, JapanLocal heavy rainfalls in urban area are drawing attentionin Japan because many people have been injured or even diedrecently due to flush floods associated with local heavyconvective rainfalls. Horizontal distributions of rainfall havebeen estimated from conventional weather radarobservations using the so-called Z-R relationship. Althoughthis relationship is relatively accurate for stratiform rain, thismethod is unreliable for convective precipitation, whichproduces heavy rainfall. It is well known that dual-polarizedradars can improve the accuracy of rainfall estimation, andthe accuracy of dual-polarized radar rainfall productsimproves with increasing rain intensity (Bringi andChandrasekar 2001). One key application of dual-polarizedradars at the operational frequency bands (S, C, and X) is theradar-based rainfall input to hydrological models (e.g.,Krajewski and Smith 2002, and Bringi et al. 2011). A varietyof rain-rate algorithms that uses the dual-polarized radardata have been proposed in the literature. Variables obtainedby the dual-polarized radars include radar reflectivity factor(Zhh), differential propagation phase (dp) and differentialreflectivity (Zdr). Because the differential reflectivity (Zdr)measured with C-band radar is more sensitive to largeraindrops associated with heavy rainfalls than is radarsoperating at other frequencies because of Mie scatteringresonance effect, the rain intensity estimated from thedifferential reflectivity (Zdr) and radar reflectivity factor(Zhh) measured with the dual-polarized C-band radar at theMeteorological Research Institute (MRI) in Tsukuba, Japanis used in the present study to analyze a local heavy rainfallevent that occurred on 7 July 2010 as a case study. Theestimate of rainfall using data from the MRI C-pol radar inthe local heavy rainfall event is compared against two opticaldisdrometers (PARSIVEL) located at about 30 km and 60 kmaway from the radar, respectively, with time intervals of 2minutes. Results show that the rainfall intensity estimatedfrom the Zdr and Zhh agrees well with the disdromterobservations and is more reliable than that estimated fromthe Z-R relationship. Moreover, the so-called high Zdrcolumn, a large differential reflectivity region was clearlyanalyzed aloft about 10 minutes prior to the local heavyrainfall on the ground, suggesting that the differentialreflectivity observed with dual-polarized C-band radar canbe a good index to detect subsequent heavy precipitationevents on the ground in advance.Adeaga, OlusegunEstimation of Terrestrial Water Storage for waterresources system managementAdeaga, Olusegun 11. Geography, University of Lagos, Lagos, NigeriaExtreme hydrological events have continued to poseserious threats to mankind with unique challenges to globalsocio-economic development and growth as aftermath. Suchchallenges demands for better understanding anddevelopment of an integrated water resources system withcapacity to accommodate the varied extreme events andexpected modification in water resources quantity andavailability at varied spatio-temporal level. The system is alsoof importance since water remains the fundamental linkbetween the climate system, human society and theenvironment. Unfortunately, suitable water resourcesassessment scheme has been greatly affected by pressure ofeconomic stringency through insufficient budget allocationand varied neglect of water resources assessmentinfrastructure. Vital information required in mosthydrological analysis for the purpose of water resourcesplanning are therefore in paucity, except for a fewcatchments. Intensive studies on hydrological processes andmechanisms have therefore being neglected for a longtimewith reported cases of station neglect while in most cases,the level and accuracy of available dataset is notcommensurate with present water developmental needs,especially in the developing countries. Paucity of groundbasedhydrological data has resulted in poor understandingof hydrologic response processes and its spatio-temporalvariability within drainage basins. Hence, Proper estimationof space-based Terrestrial Water Storage data will go a longway to provide adequate indices needed for achievingappropriate lead time information on extreme hydrologicalevents magnitude, intensity, occurrence and other waterrelated hazards. Such information will also play animportant supportive decision role in resolving practicalwater resource management and planning sinceprecipitation is invaluable as a source of renewablefreshwater. In this paper, terrestrial water storage estimationwas carried-out using 3-hourly TRMM Rainfall estimate andGRACE terrestrial water storage data in order to estimateavailable surface water distribution and its variability as wellas the uncertainty quantification for the period 2001 to2010, in Nigeria. This is necessary since adequate knowledgeon the distribution and quantification of terrestrial waterand its storage will be helpful as a measure towardsaddressing disaster prevention and water management in thedata scare region. The region is also characterizes with lowdensehydro-meteorological gauging network and little or no28