Thanks John Nissen for finding this.
In case anyone missed it, it seems to be an unofficial update to IPCC 07 by a
group of the 07 authors. Executive summary follows -one page-The full report is
at http://www.copenhagendiagnosis.com/
John Gorman
Executive Summary; The most significant recent climate change findings are:
Surging greenhouse gas emissions: Global carbon dioxide emissions from fossil
fuels in 2008 were nearly 40% higher than those in 1990. Even if global
emission rates are stabilized at present -day levels, just 20 more years of
emissions would give a 25% probability that warming exceeds 2oC. Even with zero
emissions after 2030. Every year of delayed action increase the chances of
exceeding 2oC warming.
Recent global temperatures demonstrate human-based warming: Over the past 25
years temperatures have increased at a rate of 0.190C per decade, in every good
agreement with predictions based on greenhouse gas increases. Even over the
past ten years, despite a decrease in solar forcing, the trend continues to be
one of warming. Natural, short- term fluctuations are occurring as usual but
there have been no significant changes in the underlying warming trend.
Acceleration of melting of ice-sheets, glaciers and ice-caps: A wide array of
satellite and ice measurements now demonstrate beyond doubt that both the
Greenland and Antarctic ice-sheets are losing mass at an increasing rate.
Melting of glaciers and ice-caps in other parts of the world has also
accelerated since 1990.
Rapid Arctic sea-ice decline: Summer-time melting of Arctic sea-ice has
accelerated far beyond the expectations of climate models. This area of sea-ice
melt during 2007-2009 was about 40% greater than the average prediction from
IPCC AR4 climate models.
Current sea-level rise underestimates: Satellites show great global average
sea-level rise (3.4 mm/yr over the past 15 years) to be 80% above past IPCC
predictions. This acceleration in sea-level rise is consistent with a doubling
in contribution from melting of glaciers, ice caps and the Greenland and
West-Antarctic ice-sheets.
Sea-level prediction revised: By 2100, global sea-level is likely to rise at
least twice as much as projected by Working Group 1 of the IPCC AR4, for
unmitigated emissions it may well exceed 1 meter. The upper limit has been
estimated as - 2 meters sea-level rise by 2100. Sea-level will continue to rise
for centuries after global temperature have been stabilized and several meters
of sea level rise must be expected over the next few centuries.
Delay in action risks irreversible damage: Several vulnerable elements in the
climate system (e.g. continental ice-sheets. Amazon rainforest, West African
monsoon and others) could be pushed towards abrupt or irreversible change if
warming continues in a business-as-usual way throughout this century. The risk
of transgressing critical thresholds ("tipping points") increase strongly with
ongoing climate change. Thus waiting for higher levels of scientific certainty
could mean that some tipping points will be crossed before they are recognized.
The turning point must come soon: If global warming is to be limited to a
maximum of 2oC above pre-industrial values, global emissions need to peak
between 2015 and 2020 and then decline rapidly. To stabilize climate, a
decarbonized global society - with near-zero emissions of CO2 and other
long-lived greenhouse gases - need to be reached well within this century. More
specifically, the average annual per-capita emissions will have to shrink to
well under 1 metric ton CO2 by 2050. This is 80-90% below the per-capita
emissions in developed nations in 2000.
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