Wilbur Hubbard wrote:
http://www.dailytech.com/Article.aspx?newsid=13834

Sea ice at same levels as 1979. Another nail in the coffin of global
warming alarmists and kook believers.

Wilbur Hubbard



From the National Snow and Ice Data Center

http://www.nsidc.org/arcticseaicenews/

2008 year in review

Arctic sea ice in 2008 was notable for several reasons. The year
continued the negative trend in summer sea ice extent, with the
second-lowest summer minimum since record-keeping began in 1979. 2008
sea ice also showed well-below-average ice extents throughout the entire
year.

The ice cover in 2008 began the year heavily influenced by the
record-breaking 2007 melt season. Because so much ice had melted out
during the previous summer, a vast expanse of ocean was exposed to low
winter air temperatures, encouraging ice growth. Although still well
below average, March 2008 saw slightly greater ice extent at the annual
maximum than measured in recent years. However, the ice was also thin:
less than a year old and vulnerable to melting in summer. Even the
geographic North Pole was covered with thin ice, capturing the
imaginations of many in the media and general public.

Would 2008 break the 2007 record low summer minimum extent? Would the
geographic North Pole be ice free for the first time in the satellite
era? From May through July, cooler temperatures and winds less
favorable to ice loss slowed the decline in ice extent. Nevertheless, by
August the rate of ice loss was much faster than average—even faster
than in 2007—as the effects of a warm Arctic Ocean worked against the
thin ice cover. The melt season became a race: waning sunlight versus
rapid ice loss.


Oh, and this too from the same people.

http://nsidc.org/sotc/sea_ice.html

DECLINE CAUSES

Greenhouse gases emitted through human activities and the resulting
increase in global mean temperatures are the most likely underlying
cause of the sea ice decline, but the direct cause is a complicated
combination of factors resulting from the warming, and from climate
variability. The Arctic Oscillation (AO) is a see-saw pattern of
alternating atmospheric pressure at polar and mid-latitudes. The
positive phase produces a strong polar vortex, with the mid-latitude jet
stream shifted northward. The negative phase produces the opposite
conditions. From the 1950s to the 1980s, the AO flipped between positive
and negative phases, but it entered a strong positive pattern between
1989 and 1995. So the acceleration in the sea ice decline since the mid
1990s may have been partly triggered by the strongly positive AO mode
during the preceding years (Rigor et al. 2002 and Rigor and Wallace
2004) that flushed older, thicker ice out of the Arctic, but other
factors also played a role.

Since the mid-1990s, the AO has largely been a neutral or negative
phase, and the late 1990s and early 2000s brought a weakening of the
Beaufort Gyre. However, the longevity of ice in the gyre began to change
as a result of warming along the Alaskan and Siberian coasts. In the
past, sea ice in this gyre could remain in the Arctic for many years,
thickening over time. Beginning in the late 1990s, sea ice began melting
in the southern arm of the gyre, thanks to warmer air temperatures and
more extensive summer melt north of Alaska and Siberia. Moreover, ice
movement out of the Arctic through Fram Strait continued at a high rate
despite the change in the AO. Thus warming conditions and wind patterns
have been the main drivers of the steeper decline since the late 1990s.
Sea ice may not be able to recover under the current persistently warm
conditions, and a tipping point may have been passed where the Arctic
will eventually be ice-free during at least part of the summer (Lindsay
and Zhang 2005).

Examination of the long-term satellite record dating back to 1979 and
earlier records dating back to the 1950s indicate that spring melt
seasons have started earlier and continued for a longer period
throughout the year (Serreze et al. 2007). Even more disquieting,
comparison of actual Arctic sea ice decline to IPCC AR4 projections show
that observed ice loss is faster than any of the IPCC AR4 models have
predicted (Stroeve et al. 2007).

Ultimately, summer 2008 finished with the second-lowest minimum extent
in the satellite record, 9% above the 2007 minimum and 34% below
average. A more diffuse ice cover and a thinner pack nevertheless
suggested a record-low ice volume (ice area multiplied by thickness) at
the end of summer.

As the sun set in the Arctic with the advent of autumn, seasonal ice
growth was initially quite rapid, but slowed during early November.
Average ice extent in December was well below average and very close to
that measured in 2007. Heading into 2009, the Arctic sea ice cover is
again young and thin; given this set-up, a continuation of
well-below-average sea ice extent in 2009 is a near certainty.