TY - JOUR

T1 - History of the Greenland Ice Sheet: paleoclimatic insights

AU - Alley, Richard B.

AU - Andrews, John Thomas

AU - Brigham-Grette, Julia

AU - Clarke, G. K. C.

AU - Cuffey, K. M.

AU - Fitzpatrick, J. J.

AU - Funder, Svend Visby

AU - Marshall, S. J.

AU - Miller, G. H.

AU - Mitrovica, J. X.

AU - Muhs, D. R.

AU - Otto-Bliesner, B. L.

AU - Polyak, L.

AU - White, J. W. C.

N1 - Paper id:: doi:10.1016/j.quascirev.2010.02.007

PY - 2010

Y1 - 2010

N2 - Paleoclimatic records show that the Greenland Ice Sheet consistently has lost mass in response to warming, and grown in response to cooling. Such changes have occurred even at times of slow or zero sea-level change, so changing sea level cannot have been the cause of at least some of the ice-sheet changes. In contrast, there are no documented major ice-sheet changes that occurred independent of temperature changes. Moreover, snowfall has increased when the climate warmed, but the ice sheet lost mass nonetheless; increased accumulation in the ice sheet's center has not been sufficient to counteract increased melting and flow near the edges. Most documented forcings and ice-sheet responses spanned periods of several thousand years, but limited data also show rapid response to rapid forcings. In particular, regions near the ice margin have responded within decades. However, major changes of central regions of the ice sheet are thought to require centuries to millennia. The paleoclimatic record does not yet strongly constrain how rapidly a major shrinkage or nearly complete loss of the ice sheet could occur. The evidence suggests nearly total ice-sheet loss may result from warming of more than a few degrees above mean 20th century values, but this threshold is poorly defined (perhaps as little as 2 C or more than 7 C). Paleoclimatic records are sufficiently sketchy that the ice sheet may have grown temporarily in response to warming, or changes may have been induced by factors other than temperature, without having been recorded.

AB - Paleoclimatic records show that the Greenland Ice Sheet consistently has lost mass in response to warming, and grown in response to cooling. Such changes have occurred even at times of slow or zero sea-level change, so changing sea level cannot have been the cause of at least some of the ice-sheet changes. In contrast, there are no documented major ice-sheet changes that occurred independent of temperature changes. Moreover, snowfall has increased when the climate warmed, but the ice sheet lost mass nonetheless; increased accumulation in the ice sheet's center has not been sufficient to counteract increased melting and flow near the edges. Most documented forcings and ice-sheet responses spanned periods of several thousand years, but limited data also show rapid response to rapid forcings. In particular, regions near the ice margin have responded within decades. However, major changes of central regions of the ice sheet are thought to require centuries to millennia. The paleoclimatic record does not yet strongly constrain how rapidly a major shrinkage or nearly complete loss of the ice sheet could occur. The evidence suggests nearly total ice-sheet loss may result from warming of more than a few degrees above mean 20th century values, but this threshold is poorly defined (perhaps as little as 2 C or more than 7 C). Paleoclimatic records are sufficiently sketchy that the ice sheet may have grown temporarily in response to warming, or changes may have been induced by factors other than temperature, without having been recorded.

U2 - 10.1016/j.quascirev.2010.02.007

DO - 10.1016/j.quascirev.2010.02.007

M3 - Journal article

VL - 29

SP - 1728

EP - 1756

JO - Quaternary Science Reviews

JF - Quaternary Science Reviews

SN - 0277-3791

IS - 15-16

ER -