HR: 0830h
AN: C41C-0983    [PDF]
TI: From the Sun to the Ice - Then Where? A Bi-polar, Integrated View of the Role of Polar Snow and Floating Ice Covers in the Earth's Heat Budget During IPY 2007/08
AU: * Eicken, H
EM: hajo.eicken@gi.alaska.edu
AF: Geophysical Institute University of Alaska Fairbanks, POB 757320, Fairbanks, AK 99775-7320
AU: Grenfell, T
EM: tcg@atmos.washington.edu
AF: Dept. of Atmospheric Sciences University of Washington, POB 351640, Seattle, WA 98195-1640
AU: Jeffries, M
EM: martin.jeffries@gi.alaska.edu
AF: Geophysical Institute University of Alaska Fairbanks, POB 757320, Fairbanks, AK 99775-7320
AU: Perovich, D
EM: perovich@crrel.usace.army.mil
AF: Cold Regions Research and Engineering Laboratory, 72 Lyme Rd., Hanover, NH 03775
AU: Sturm, M
EM: msturm@crrel.usace.army.mil
AF: Cold Regions Research and Engineering Laboratory, POB 35170, Ft. Wainwright, AK 99703-0170
AB: The polar regions play a key role in the disposition of energy and in particular solar radiation in the earth's climate system. With the largest seasonal variations in surface albedo occurring over the polar oceans and with substantial changes in the extent and nature of the snow and ice covers in recent decades, the polar regions are a critical link between top-of-the atmosphere radiative fluxes and solar energy absorbed by the earth system. While recent studies have greatly improved our knowledge of the heat budget of the polar oceans, we are still far from understanding a number of fundamental questions related to the role of snow and ice in the global radiation budget and their importance for albedo feedback processes. For example, currently albedo parameterizations in large-scale sea ice and climate models are only partially successful in taking into account the physical processes driving seasonal and interannual albedo changes. In fact, the majority of models employ different albedo parameterizations for northern and southern hemisphere snow and sea ice. This is dictated by the strong contrasts in snow and ice melt processes in Arctic and Antarctic, which in of themselves are not all that well understood. Our own research in the Western Arctic and in the southern Ross Sea indicates that snow may play a crucial, currently underestimated role in governing these processes and hence the nature and magnitude of ice-albedo feedback processes. Here, we propose that an integrated, bi-polar examination of the interaction between snow and floating ice covers (sea and lake ice), coupled with a global-scale analysis of the role of polar ice masses in affecting the earth's radiation budget would provide an interesting and scientifically significant cryospheric thread within the framework of the IPY 2007/08. This work would also address other important aspects such as large-scale cloud radiative forcing over ice surfaces and spatio-temporal partitioning of the radiation reaching the surface. At the same time, such a program would provide direct linkages to the aims of the International Heliospheric Year. The observational effort would comprise a pan-polar approach to ground-based measurements along with satellite remote sensing, augmented by numerical simulations. Based on studies of the energy and mass balance of Arctic and Antarctic snow and ice covers, we will show how such a cryospheric component could be integrated into the overall aims of the IPY. IPY will provide an extraordinary opportunity to capture the imagination of the general public and school children. Our proposed effort will take advantage of this opportunity to convey information about the solar radiation and about the role the polar regions play in global climate. There will be an extensive educational outreach component that will include media contacts, web sites, classroom programs, and public lectures. Examples of such approaches, e.g., the Alaska Lake Ice and Snow Observatory Network (ALISON, www.gi.alaska.edu/alison) or Barrow Coastal Ice Observations (www.arcticice.org) will be discussed.
DE: 0360 Transmission and scattering of radiation
DE: 1863 Snow and ice (1827)
DE: 4540 Ice mechanics and air/sea/ice exchange processes
SC: Cryosphere [C]
MN: 2003 Fall Meeting