Climate Impacts Potentially Immense, Overwhelming
March 30, 2014
The Intergovernmental Panel on Climate Change Working Group II report is now out.
This is the second of a series from the Intergovernmental Panel on Climate Change (IPCC) due out this year that outlines the causes, effects and solutions to global warming.
This latest Summary for Policymakers document highlights the fact that the amount of scientific evidence on the impacts of warming has almost doubled since the last report in 2007.
In the words of the report, “increasing magnitudes of warming increase the likelihood of severe, pervasive and irreversible impacts”.
“Before this we thought we knew this was happening, but now we have overwhelming evidence that it is happening and it is real,” said Dr Saleemul huq, a convening lead author on one of the chapters.
Michel Jarraud, secretary-general of the World Meteorological Organization, said that, previously, people could have damaged the Earth’s climate out of “ignorance”.
“Now, ignorance is no longer a good excuse,” he said.
The report details significant short-term impacts on natural systems in the next 20 to 30 years. It details five reasons for concern that would likely increase as a result of the warming the world is already committed to.
These include threats to unique systems such as Arctic sea ice and coral reefs, where risks are said to increase to “very high” with a 2C rise in temperatures.
As grim as the Working Group 2 report on impacts is, it explicitly has very little to say about the catastrophic impacts and vulnerability in the business as usual case where the Earth warms 4°C to 5°C [7°F-9°F] — and it has nothing to say about even higher warming, which the latest science suggests we are headed toward.
The report states:
“Relatively few studies have considered impacts on cropping systems for scenarios where global mean temperatures increase by 4°C [7°F] or more.
“… few quantitative estimates [of global annual economic losses] have been completed for additional warming around 3°C [5.4°F] or above.”
D’oh! You may wonder why hundreds of the world leading climate experts spend years and years doing climate science and climate projections, but don’t bother actually looking at the impacts of merely staying on our current carbon pollution emissions path — let alone looking at the plausible worst-case scenario (which is typically the basis for risk-reducing public policy, such as military spending).
Partly it’s because, until recently, climate scientists had naively expected the world to act with a modicum of sanity and avoid at all costs catastrophic warming of 7°F let alone the unimaginable 10°F (or higher) warming we are headed toward. Partly it’s because, as a recent paper explained, “climate scientists are biased toward overly cautious estimates, erring on the side of less rather than more alarming predictions.”
On top of the overly cautious nature of most climate scientists, we have the overly cautious nature of the IPCC. As the New York Times explained when the IPCC released the Working Group 1 report last fall:
“The I.P.C.C. is far from alarmist — on the contrary, it is a highly conservative organization,” said Stefan Rahmstorf of the Potsdam Institute for Climate Impact Research in Germany, whose papers on sea level were among those that got discarded. “That is not a problem as long as the users of the I.P.C.C. reports are well aware of this. The conservatism is built into its consensus structure, which tends to produce a lowest common denominator on which a large number of scientists can agree.”
That’s why the latest report is full of these sorts of bombshells couched in euphemism and buried deep in the text:
By 2100 for the high-emission scenario RCP8.5, the combination of high temperature and humidity in some areas for parts of the year is projected to compromise normal human activities, including growing food or working outdoors.
Yes, “compromise.” A clearer word would be “obliterate.” And the “high-emission scenario RCP8.5″ — an atmospheric concentration of carbon dioxide of about 936 parts per million — is in fact where we are headed by 2100 or soon thereafter on our current do-little path.
Bottom line: We are at risk of making large parts of the planet’s currently arable and populated land virtually uninhabitable for much of the year — and irreversibly so for hundreds of years.
The devastating effects of recent extreme events and extreme weather disasters also prove that our ability to adapt to a changing climate is low, according to the report.
If left unchecked, the report finds that climate-change risks include:
•Coastal flooding, which will devastate areas near the shore.
•Widespread hunger due to warming, drought and severe downpours.
•Damage to big cities because of inland flooding.
•Extreme weather and storms, damaging some of the things we take for granted, like electricity, running water and emergency services.
“We live in an era of man-made climate change,” said Vicente Barros, co-chair of the group that prepared the report. “In many cases, we are not prepared for the climate-related risks that we already face.”