adaptation
; Antarctica
; article
; glacier
; greenhouse effect
; greenhouse gas
; Greenland
; ice sheet
; physical model
; priority journal
; sea level
; simulation
; thermal analysis
; time
; chemistry
; computer simulation
; ice cover
; sea
; temperature
; theoretical model
; sea water
; Antarctic Regions
; Computer Simulation
; Global Warming
; Greenland
; Ice Cover
; Models, Theoretical
; Oceans and Seas
; Seawater
; Temperature
英文摘要:
Global mean sea level has been steadily rising over the last century, is projected to increase by the end of this century, and will continue to rise beyond the year 2100 unless the current global mean temperature trend is reversed. Inertia in the climate and global carbon system, however, causes the global mean temperature to decline slowly even after greenhouse gas emissions have ceased, raising the question of how much sea-level commitment is expected for different levels of global mean temperature increase above preindustrial levels. Although sealevel rise over the last century has been dominated by ocean warming and loss of glaciers, the sensitivity suggested from records of past sea levels indicates important contributions should also be expected from the Greenland and Antarctic Ice Sheets. Uncertainties in the paleo-reconstructions, however, necessitate additional strategies to better constrain the sea-level commitment. Here we combine paleo-evidence with simulations from physical models to estimate the future sea-level commitment on a multimillennial time scale and compute associated regional sea-level patterns. Oceanic thermal expansion and the Antarctic Ice Sheet contribute quasi-linearly, with 0.4 m °C -1 and 1.2 m °C-1 of warming, respectively. The saturation of the contribution from glaciers is overcompensated by the nonlinear response of the Greenland Ice Sheet. As a consequence we are committed to a sea-level rise of approximately 2.3 m °C-1 within the next 2,000 y. Considering the lifetime of anthropogenic greenhouse gases, this imposes the need for fundamental adaptation strategies on multicentennial time scales.
Levermann, A., Potsdam Institute for Climate Impact Research, 14473 Potsdam, Germany, Institute of Physics, Potsdam University, 14476 Potsdam, Germany; Clark, P.U., College of Earth, Ocean, and Atmospheric Sciences, Oregon State University, Corvallis, OR 97331, United States; Marzeion, B., Center for Climate and Cryosphere, Institute for Meteorology and Geophysics, University of Innsbruck, 6020 Innsbruck, Austria; Milne, G.A., Department of Earth Sciences, University of Ottawa, Ottawa, ON K1N 6N5, Canada; Pollard, D., Earth and Environmental Systems Institute, Pennsylvania State University, University Park, PA 16802, United States; Radic, V., University of British Columbia, Vancouver, BC V6T 1Z4, Canada; Robinson, A., Universidad Complutense de Madrid, 28040 Madrid, Spain, Instituto de Geociencias, Universidad Complutense de Madrid-Consejo Superior de Investigaciones Científicas, 28040 Madrid, Spain
Recommended Citation:
Levermann A.,Clark P.U.,Marzeion B.,et al. The multimillennial sea-level commitment of global warming[J]. Proceedings of the National Academy of Sciences of the United States of America,2013-01-01,110(34)