the explorers journal the climate change issue - The Explorers Club

southern victoria land
antartica
Mt. Erebus, the only active volcano exposed on the Antarctic
continent; the massive Ross Ice Shelf, which drains glaciers
flowing out of the Transantarctic Mountains and portions of
West Antarctica; and the city block-size icebergs spawned off
the ice shelf can be seen from the coast of Southern Victoria
Land, East Antarctica.
Arctic), allowing solar radiation to penetrate to the
surface, and along with the global rise in CO 2
,
CH 4
, and N 2
O, provides immense potential for climate
change over the Southern Hemisphere. The
Southern Ocean is our most biologically productive
ocean and a significant sink for both heat and
CO 2
, making it critical to the evolution of climate
past and present. Therefore it acts as a wild card
for future climate change that is human-induced.
The Arctic Ocean is expected to be nearly ice
free by the latter twenty-first century in response to
greenhouse gas warming. In the process, habitats
and lifestyles throughout the Arctic will continue to
change dramatically. A climate surprise portented
by our ice core research in Greenland may appear
in the cooling of northern Europe, induced through
warming, which increases Arctic ice melt. This in
turn increases the influx of fresh water into the North
Atlantic. The salinity decrease as a consequence
of the freshening in the Arctic may be sufficient to
reduce the density of North Atlantic surface water,
leading to a reduction in deepwater production and,
as a consequence, reduced heat transport to northern
Europe. In addition, changes in precipitation
and atmospheric circulation are evolving over the
Northern Hemisphere as a result of warming over
the Arctic and lower latitudes.
Temperatures of the last few decades are the
highest recorded in the instrumental era—the
last 100 years—and through examination of temperature
reconstructions utilizing ice core, tree
ring, historical, and other data series, it is clear
that Northern Hemisphere temperatures are the
highest of at least the last millennium. This finding,
repeated by several investigators and validated by
numerous reviews of the data, is a consequence
26 the explorers journal