HR: 15:10h
AN: U33B-07    [Abstracts]
TI: An Intensified Arctic Water Cycle? Trend Analysis of the Arctic System Freshwater Cycle: Observations and Expectations
AU: * Rawlins, M A
EM: michael.rawlins@unh.edu
AF: Water Systems Analysis Group, University of New Hampshire, Durham, NH 03842, United States
AU: Adam, J C
EM: jadam@u.washington.edu
AF: Department of Civil & Environmental Engineering, University of Washington, Box 352700, Seattle, WA 98195, United States
AU: Vorosmarty, C J
EM: charles.vorosmarty@unh.edu
AF: Water Systems Analysis Group, University of New Hampshire, Durham, NH 03842, United States
AU: Serreze, M C
EM: serreze@kryos.colorado.edu
AF: CIRES, University of Colorado, Boulder, CO 80309, United States
AU: Hinzman, L D
EM: ffldh@uaf.edu
AF: International Arctic Research Center, University of Alaska Fairbanks, P.O. Box 757340, Fairbanks, AK 99775, United States
AU: Holland, M
EM: mholland@cgd.ucar.edu
AF: National Center for Atmospheric Research, PO BOX 3000, Boulder, CO 80307, United States
AU: Shiklomanov, A
EM: alex.shiklomanov@unh.edu
AF: Water Systems Analysis Group, University of New Hampshire, Durham, NH 03842, United States
AB: It is expected that a warming climate will be attended by an intensification of the global hydrological cycle. While there are signs of positive trends in several hydrological quantities emerging at the global scale, the scope, character, and quantitative significance of these changes are not well established. In particular, long-term increases in river discharge across Arctic Eurasia are assumed to represent such an intensification and have received considerable attention. Yet, no change in long-term annual precipitation across the region can be related with the discharge trend. Given linkages and feedbacks between the arctic and global climate systems, a more complete understanding of observed changes across northern high latitudes is needed. We present a working definition of an accelerated or intensified hydrological cycle and a synthesis of long-term (nominally 50 years) trends in observed freshwater stocks and fluxes across the arctic land-atmosphere-ocean system. Trend and significance measures from observed data are described alongside expectations of intensification based on GCM simulations of contemporary and future climate. Our domain of interest includes the terrestrial arctic drainage (including all of Alaska and drainage to Hudson Bay), the Arctic Ocean, and the atmosphere over the land and ocean domains. For the terrestrial Arctic, time series of spatial averages which are derived from station data and atmospheric reanalysis are available. Reconstructed data sets are used for quantities such as Arctic Ocean ice and liquid freshwater transports. Study goals include a comprehensive survey of past changes in freshwater across the pan-arctic and a set of benchmarks for expected changes based on an ensemble of GCM simulations, and identification of potential mechanistic linkages which may be examined with contemporary remote sensing data sets.
DE: 1600 GLOBAL CHANGE
DE: 1637 Regional climate change
DE: 1655 Water cycles (1836)
DE: 1833 Hydroclimatology
SC: Union [U]
MN: 2007 Fall Meeting