Jason E. Box,1,2 Noel Cressie,3,4 David H. Bromwich,1,2 Ji-Hoon Jung,1,2 Michiel van den Broeke,5 J. H. van Angelen,5 Richard R. Forster,6 Clement Miège,6 Ellen Mosley-Thompson,1,2 Bo Vinther,7 and Joseph R.McConnell8
4 National Institute for Applied Statistics Research Australia (NIASRA), University of Wollongong, Wollongong, New South Wales, Australia
We find a 12% or 86 Gt y-1 increase in ice sheet accumulation rate from the end of the Little Ice Age in ~1840 to the last decade of the reconstruction. This 1840-1996 trend is 30% higher than that of 1600-2009, suggesting an accelerating accumulation rate. The correlation of Ât(G) with the average surface air temperature in the Northern Hemisphere(SATNHt) remains positive through time, while the correlation of Ât(G) with local near-surface air temperatures or North Atlantic sea surface temperatures is inconsistent, suggesting a hemispheric-scale climate connection. We find an annual sensitivity of Ât(G) to SATNHt of 6.8% K-1 or 51 Gt K-1.
The reconstuction, Ât(G), correlates consistently highly with the North Atlantic Oscillation index. Yet, at the 11-year time scale, the sign of this correlation flips four times in the 1870-2005 period.