Latest warming report draws a line not to cross

Greenland ice
This 2009 file photo shows Ice Fjord of Ilulissat in Greenland. The Greenland ice sheet has lost 1,500 billion tons of ice since 2000.
AFP/AFP/Getty Images

U.N. Secretary-General Ban Ki-moon greeted the release of the latest world report on climate change with the words, "Now we must act."

The U.N.-appointed Intergovernmental Panel on Climate Change issued its fifth assessment last week, and this one went further than its predecessors. The IPCC found at least a 95 percent chance that global warming is being caused by human activity and set a limit for the amount of greenhouse gases that the world community should release into the atmosphere.

More than 1 trillion tons of carbon in the atmosphere, the panel decided, would risk the worst effects of global warming. The world is already more than halfway there. Presumably, the world's governments would need to require some kind of containment — underground storage, for example — to keep future carbon releases from pushing the atmosphere over the limit.

The New York Times reports that "at current rates of energy consumption, the trillionth ton will be released around 2040, according to calculations by Myles R. Allen, a scientist at the University of Oxford and one of the authors of the new report. More than 3 trillion tons of carbon are still left in the ground as fossil fuels."

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The Daily Circuit checks in with MPR News Meteorologist Paul Huttner and other scientists to discuss the report and its ramifications.


Global Warming Slowdown Complicates IPCC's Job
Even though the greenhouse gas emissions keep rising, the global warming has slowed down in past 15 years. Scientists are working on a U.N. report how to address this wrinkle in the meteorological data. (Pentagon Post)

IPCC report: skeptic groups launch global anti-science campaign
Because the IPCC's conclusions are produced by a consensus process, they are inherently conservative. ...

In addition, scientists have become more proactive when it comes to squashing scientific inaccuracies pushed by skeptic groups. Dozens of prominent scientists involved with drafting IPCC reports formed a Climate Science Rapid Response Team that punches back against misleading claims about climate research. (The Guardian)

IPCC climate report: humans 'dominant cause' of warming
For the future, the report states that warming is projected to continue under all scenarios. Model simulations indicate that global surface temperature change by the end of the 21st Century is likely to exceed 1.5 degrees Celsius, relative to 1850. Prof. Sir Brian Hoskins, from Imperial College London, told BBC News: "We are performing a very dangerous experiment with our planet, and I don't want my grandchildren to suffer the consequences of that experiment." (BBC)