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1995-2005 was no different from that of the decade 1923-1933. Therefore, “based on the
simulations of these two periods,” according to Wake et al., “it could as well be stated that the
recent changes that have been monitored extensively (Krabill et al., 2004; Luthcke et al., 2006;
Thomas et al., 2006) are representative of natural sub-decadal fluctuations in the mass balance
of the ice sheet and are not necessarily the result of anthropogenic-related warming.”
Contemporaneously, Ettema et al. (2009) applied a regional atmospheric climate model over a
domain that included the Greenland Ice Sheet and its surrounding oceans and islands at what
they described as an “unprecedented high horizontal resolution (~11 km),” which for use over
Greenland was coupled to a physical snow model that treated surface albedo as a function of
snow/firn/ice properties, meltwater percolation, retention and refreezing. The atmospheric
part of this model was forced at the lateral boundaries and the sea surface by the global model
of the European Centre for Medium-Range Weather Forecasts for the period September 1957
to September 2008. This work revealed the “total annual precipitation in the Greenland ice
sheet for 1958-2007 to be up to 24% and surface mass balance up to 63% higher than
previously thought,” with the largest differences occurring in coastal southeast Greenland,
where the seven scientists said that the much higher-resolution facilitates captured snow
accumulation peaks that past five-fold coarser resolution regional climate models missed.
Averaged over the entire study period, the total ice sheet’s SMB was 469 ± 41 Gt per year; and
before 1990 none of the mass balance components exhibited a significant trend. Since 1990,
however, there has been a slight downward trend in Greenland’s SMB of 12 ± 4 Gt per year,
which is probably not all that significant, considering the fact that over the one-year-period
1995 to 1996 its SMB rose by a whopping 250%. With respect to the stability/longevity of the
Greenland Ice Sheet, therefore, Ettema et al. state that “considerably more mass accumulates
on the Greenland Ice Sheet than previously thought, adjusting upwards earlier estimates by as
much as 63%,” which suggests that the Northern Hemisphere’s largest ice sheet may well hang
around a whole lot longer than many climate alarmists have been willing to admit.
In the Southern Hemisphere, Cofaigh et al. (2001) analyzed five sediment cores from the
continental rise west of the Antarctic Peninsula and six from the Weddell and Scotia Seas for
their ice rafted debris (IRD) content in an attempt to determine if there are Antarctic analogues
of the Heinrich layers of the North Atlantic Ocean, which testify of the repeated collapse of the
eastern margin of the Laurentide Ice Sheet and the concomitant massive discharge of icebergs.
This they did because if such IRD layers exist around Antarctica, they reasoned they would be
evidence of “periodic, widespread catastrophic collapse of basins within the Antarctic Ice
Sheet,” which could obviously occur again. After carefully analyzing their data, however, they
concluded that “the ice sheet over the Antarctic Peninsula did not undergo widespread
catastrophic collapse along its western margin during the late Quaternary,” and that this
evidence “argues against pervasive, rapid ice-sheet collapse around the Weddell embayment
over the last few glacial cycles.” Therefore, if there was no dramatic break-up of the Antarctic
Ice Sheet “over the last few glacial cycles,” there’s a good chance there will also be none before
the current interglacial ends. And since the data of Petit et al. (1999) indicate that each of the
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