This fall the United Nations Intergovernmental Panel on Climate Change (IPCC) will publish its fifth “Assessment Report” (AR) with predictions for greenhouse gas emissions and global temperature impacts during this century ending 2100. Since its founding in 1988, the IPCC has produced these ARs about every six years – in 1990, 1995, 2001 and 2007.
The IPCC has been the primary intergovernmental organization for global climate change research funding, greenhouse gas control regulations and climate-carbon activism. Rajendra Pachauri has been Chairman of the IPCC for over a decade. Pachauri was jointly awarded the Nobel Peace Prize with Al Gore in 2007. Pachauri, an Indian engineer with a Ph.D. in economics, has been the principal promoter of the U.N.’s apocalyptic narrative that global warming from manmade greenhouse gases is an immediate and existential threat to life on Planet Earth. This year Pachauri has acknowledged that global warming has been “at a standstill” in recent decades.
Last month The Economist reported some early draft findings of the forthcoming “Fifth IPCC Assessment Report.” These findings reflect new variability in climate “sensitivity” to predicted atmospheric carbon levels. They further suggest: 1) a growing U.N. sense that climate impacts may have been overestimated in the past, and 2) climate science is too uncertain to justify a single estimate of future rises.
Here are past IPCC Assessment Report estimates of climate change impacts to end-of-century (2100) temperatures and sea level rise:
• AR 1990 estimated max. temp. rise of 4.5 degrees C and sea level rise of 1 meter (3.3 ft.);
• AR 1995 estimated max. temp. rise of 3.5 degrees C and sea level rise of 95 cm (3 ft.);
• AR 2001 estimated max. temp. rise of 5.8 degrees C and sea level rise of 88 cm (2.8 ft.);
• AR 2007 estimated most likely temp rise of 2 degrees C, no sea level rise estimated;
• Draft AR 2013 estimated most likely temp. rise 1.5 degrees C, no sea level rise estimated.
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