Climate Change: Arctic Sea Ice heading for Rapid
Disintegration
IndyMedia, Sydney
Posted October 12th, 2007 by takver
Arctic summer sea ice is headed towards rapid disintegration as early as
2013, a century ahead of the International Panel on Climate Change (IPCC)
projections, according to 'the Big Melt' (PDF), a new review of recent
scientific literature on climate change produced by
http://www.carbonequity.info/.
We have gone past the tipping point for Arctic sea ice and now we
watch the disintegration of the Greenland and the West Antarctic ice
sheets which will result in catastrophic changes in sea level of 5
metres or more in the next 100 years.
These changes are happening at much lower average temperature rises than
predicted. The rapid loss of Arctic sea ice will speed up the
disintegration of the Greenland ice sheet. Scientists are still arguing
over the impact on the thermo-haline circulation or the Great Ocean
Conveyor belt that transports heat in the oceans around the world from
the Pacific to the North Atlantic and back. This great current has
already slowed by a third by some measurements. The release of vast
amounts of fresh water from the Greenland Ice cap may cause the current
to stop for a period or produce another climate tipping point that will
heavily impact the climate of east coast North America and Northern
Europe.
"Every now and then enough fresh water goes into the North Atlantic
that it actually stops its circulation," Dr Timothy Burrows said
"And when that happens Europe cools dramatically," he said. Dr
Burrows, a paleoclimatologist at the Australian National University,
made these remarks in an article just published in Science journal
detailing that Australia may not be affected as much as northern
hemisphere countries if and when the next Ice Age hits. "The way
our world works, we actually transport heat from the southern hemisphere
into the north, because of this ocean conveyer belt," he said.
"And when you stop that, the heat doesn't have anywhere to go and
it accumulates in the southern hemisphere." he was reported the
Sydney Morning Herald.
The disintegration of the Arctic Sea Ice will also curtail polar bear
populations, presently numbering about 22,000. Polar bears rely on sea
ice to live and hunt for their prey. Reports prepared for the US
Geological Survey and released in September 2007 say that two-thirds the
world's polar bears could be threatened with extinction by 2050. If
Summer sea ice vanishes on a quicker timetable, so will the polar bear,
the largest of the carnivorous mammals.
With the reduction in the sea ice extent, there is increasing activity
to explore and later exploit the oil and mineral resources under the
arctic sea. One study has estimated that a quarter of the world's oil
and gas reserves might be found in the region, as well as significant
deposits of other mineral riches. So the rush is on for claims by the
five countries with territory inside the Arctic Circle - Russia, the US,
Norway, Denmark and Canada. Use of the Northwest passage for a short
route for shipping from the Atlantic to Asia is also in dispute with
Canada asserting it has a right to control, regulate and tax shipping.
America and the European Union say the passage is an international
strait and that all foreign ships have the right of "transit
passage." But it will probably be sometime before commercial
shipping lines judge the cost benefit is greater than the increased
risk.
Arctic Sea Ice Extent Decline: Graphs from 'the Big Melt -
Lessons from the Arctic summer of 2007' available from carbonequity.info,
October 2007
Carbon Dioxide Growing more Rapidly than Business As Usual
Projections Carbon dioxide emissions are now growing more rapidly
than "business as usual", and at a much greater rate than the
more pessimistic forecasts in IPCC scenarios. The US and Australia are
still refraining from signing the Kyoto protocol and setting minimal
progressive targets for greenhouse gas reduction. At the recent APEC
meeting in Sydney a Climate Declaration was signed which only had
non-binding aspirational targets.
Sea level rise already affects people such as the Carteret Islanders
forced to evacuate their homes. (Listen to them on this video by Pip
Starr). On the impact of sea level rise the report states that
"one-quarter of Bangladesh's population (~35 million people) lives
within the coastal floodplain. Many of the world's major cities (22 of
the top 50) are at risk of flooding from coastal surges, including
Tokyo, Shanghai, Hong Kong, Mumbai, Calcutta, Karachi, Buenos Aires, St
Petersburg, New York, Miami and London. In almost every case, the city
relies on costly flood defences for protection. Even if protected, these
cities would lie below sea level with a residual risk of flooding like
New Orleans today. The homes of tens of millions more people are likely
to be affected by flooding from coastal storm surges with rising sea
levels. People in South and East Asia will be most vulnerable, along
with those living on the coast of Africa and on small islands"
(Stern, 2006b). A rise of 5 metres would affect 669 million people and 2
million square kilometres of land of land would be lost (Kahn,
2007)."
Rising sea levels will also impact underground freshwater acquirfers
which more than 2 billion peopledepend on. These acquifers will become
contaminated by the salt water producing a crisis in drinking water in
cities such as Shanghai, Manila, Jakarta, Bangkok, Kolkata, Mumbai,
Karachi, Lagos, Buenos Aires and Lima. "The water supplies of
dozens of major cities around the world are at risk from a previously
ignored aspect of global warming. Within the next few decades rising sea
levels will pollute underground water reserves with salt... Long before
the rising tides flood coastal cities, salt water will invade the porous
rocks that hold fresh water... The problem will be compounded by sinking
water tables due to low rainfall, also caused by climate change, and
rising water usage by the world's growing and increasingly
urbanisedpopulation" (Pearce, 2006a).
If you want to see the impact of sea level rise on coastal geography
visit http://flood.firetree.net/ for a Google earth mashup showing what
a 1m to 14 m rise in sea level might do.
Scientific reticence and Diplomatic and political conservatism
The IPCC reports, have suffered from a scientific and diplomatic
reticence and conservatism which has under-estimated the extent, impact
and speed of climate change. The report quotes Barry Pittock, an
Australian CSIRO scientist on the limitations of the IPCC process:
"Vested interests harboured by countries heavily reliant on fossil
fuels for industry and development, or for export, lead to pressure to
remove worst case estimates; scientists... tend to focus on "best
estimates", which they consider most likely, rather than worst
cases that may be serious but which have only a small probability of
occurrence; many scientists prefer to focus on numerical results from
models, and are uncomfortable with estimates based on known but
presently un-quantified mechanisms; and due to the long (four-year)
process of several rounds of drafting and peer and government review, an
early cut-off date is set for cited publications" (often a year
before the reports appear)."
The report heavily criticized the IPCC process saying "The data
surveyed suggests strongly that in many key areas the IPCC process has
been so deficient as to be an unreliable and indeed a misleading basis
for policy-making." and that "The primary assumptions on which
climate policy is based need to be re-interrogated."
"Take just one example: the most fundamental and widely supported
tenet - that 2�C represents a reasonable maximum target if we are to
avoid dangerous climate change - can no longer be defended. Today at
less than a 1�C rise the Arctic sea ice is headed for very rapid
disintegration, in all likelihood triggering the irreversible loss of
the Greenland ice sheet and catastrophic sea level increases. Many
species are on the precipice, climate-change-induced drought or changing
monsoon patterns are sweeping every continent, the carbon sinks are
losing capacity and the seas are acidifying."
The report urges in the conclusion that "The simple imperative is
for us to very rapidly decarbonise the world economy and to put in place
the means to draw down the existing excess CO2 levels. We must choose
targets and take actions that can actually solve the problem in a timely
way. It is too late not to be honest with ourselves and our fellow
citizens."
This report does not propose solutions, although elsewhere on
carbonequity.info you can find discussion and proposals for carbon
rationing, carbon taxes, and links to articles on increasing energy
efficiency and renewable energy. What it does advocate is that political
leaders need to make the hard decisions now to set binding targets on
climate emissions and set in place the essential regulatory framework
and infrastructure for a carbon neutral society, and establish a system
where atmospheric carbon is reduced to stand a reasonable chance of
limiting impacts on society.
If you don't believe we are facing a climate disaster, then read the
report, and its extensive scientific references.
Sources:
� 'the Big Melt' (PDF), a new review of recent scientific literature on
climate change produced by http://www.carbonequity.info/. Published 6
October 2007.
� Sydney Morning Herald October 5, 2007 - Ice ages affect Australia
less: expert. See also ABC radio, The World Today October 5, 2007 - New
ice age might not affect Australia: research
� Mongabay.com September 7, 2007 - Two-thirds of polar bears at risk of
extinction by 2050
� Ethical Corporation, October 5, 2007 - Politics: Polar resources -
The next cold war See also Energy Bulletin, October 10, 2007 An oil
& gas Shangri-la in the Arctic?
� The New York Sun October 11, 2007 - Northwest Passage Open for
Business - Strife Looms Between U.S., Canada
� NASA - Record Arctic Sea Ice Loss in 2007
� NASA 15 May 2007 - NASA Finds Vast Regions of West Antarctica Melted
in Recent Past
� NASA 20 September 2007 - NASA Researchers Find Snowmelt in Antarctica
Creeping Inland
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