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

Wood, Eric F.Challenges in Developing Long-term Climate DataRecords for the Terrestrial Water and Energy CyclesINVITEDWood, Eric F. 1 ; Pan, Ming 1 ; Sahoo, Alok K. 1 ; Troy, Tara J. 3 ;Vinukollu, Raghuveer K. 2 ; Sheffield, Justin 11. Dept Civil & Environmental Engineering, PrincetonUniversity, Princeton, NJ, USA2. Swiss Re, Armonk, NY, USA3. Columbia Univsersity, New York, NY, USAComprehensive documentation of the terrestrial watercycle at the global scale and its evolution over time isfundamental to understanding Earth’s climate system andassessing the impacts due to climate change. Suchdocumentation is also needed to characterize the memories,pathways and feedbacks between key water, energy andbiogeochemical cycles. With such enhanced understanding,there is the potential for research programs to resolveoverarching scientific goals to document the energy andwater cycles. GEWEX’s long-term scientific goal is to obtaina quantitative description of weather-scale variations in theglobal energy and water cycles over a period of at least 20years, which will provide the needed scientific basis forunderstanding climate variability and change. Such longtermdata sets have been referred to as Earth System DataRecords (ESDRs) by NASA’s MEaSUREs program, ClimateData Records (CDRs) by NOAA’s National Climatic DataCenter and the European Organization for the Exploitationof Meteorological Satellites (EUMETSAT). In developingglobal-scale climate data records, satellite-based observationsoffer global consistency that can fill spatial-temporal gaps inground-based data collection. Observations from satellitemissions over the last two decades are already providingimportant observations that are being used to developCDRs. In this presentation the underlying challenges will bediscussed in using remote sensing based variables fordeveloping long-term CDRs for the terrestrial water andenergy budget variables. These challenges include temporalconsistency among sensors and algorithms on differentsatellites, uncertainty in retrieval algorithms, and lack ofbudget closure when using the independently estimatedterms. Recent results show that using multiple remotesensing estimates, merged with in-situ and model estimatesand applying budget closure constraints can lead toconsistent long-term CDRs. These CDRs will be used toassess variability and trends in regional and global water andenergy budgets.Worden, JohnConstraints on High Latitude Moisture Fluxes andContinental Recycling Using Satellite and AircraftMeasurements of Water Vapor IsotopesWorden, John 1 ; Lee, Jung-Eun 1 ; Cherry, Jessie 2 ; Risi, Camille 4 ;Frankenberg, Christian 1 ; Welker, Jeff 2 ; Cable, Jessie 2 ; Noone,David 31. JPL / California Institute of Techonology, Pasadena, CA,USA2. University of Alaska Fairbanks, Fairbanks, AK, USA3. University of Colorado, Boulder, CO, USA4. Le Laboratoire de Météorologie Dynamique, Paris, FranceChanges in the water cycle at high latitudes couldsubstantially change the global energy balance due to severalpositive and negative feedbacks. For example, the decrease inthe arctic ice cap can have a positive feedback resulting fromthe decreased albedo and increased water vapor in theatmosphere. The change in cloud cover can be either apositive or negative feedback. If the frequency of snowfallincreases as a result of increased moisture, it would be anegative feedback because fresh snow has higher albedo thanold snow or bare ground. Characterizing the distribution ofthe moisture sources, rainfall, continental recycling and theprocesses controlling cloud distributions are then critical forunderstanding how changes in the polar sea ice and snowdistributions will affect future climate. Measurements ofwater isotopes can place constraints on the distribution ofthese processes because local and transported water vaporhave different isotope signals . In this poster we use newmeasurements of water vapor isotopes from the Aura TESand JAXA GOSAT satellites, in situ measurements fromground and aircraft, and the LMDz model to examine thedistribution of moisture sources at high latitudes and toestimate the amount of continental recycling.Xaver, AngelikaRecent progress on the International Soil MoistureNetworkXaver, Angelika 1 ; Gruber, Alexander 1 ; Hegyiova, Alena 1 ;Dorigo, Wouter A. 1 ; Drusch, Matthias 21. Institute of Photogrammetry & Remote Sensing, ViennaUniversity of Technology, Vienna, Austria2. ESTEC, European Space Agency, Noordwijk, NetherlandsFor the calibration and validation of satellite- and landsurface model based soil moisture estimates in situ soilmoisture measurements are indispensable. Although acouple of meteorological networks measuring soil moistureexist, on a global and long-term scale, ground-basedobservations are few. In addition, measurements fromdifferent networks are performed in quite different ways,resulting in significant disparities, e.g., with respect to soilmoisture units, measurement depths, and sampling rates.This has been the reason for initiating the International SoilMoisture Network (ISMN;http://www.ipf.tuwien.ac.at/insitu/), a centralized data153