Last week’s report from the Intergovernmental Panel on Climate Change reaffirmed the scientific consensus that global warming is happening and is primarily caused by human use of fossil fuels (coal, oil and natural gas) for our energy needs.
For the first time, however, the IPCC stated an upper limit on total greenhouse gas emissions — a global “carbon budget” to keep temperature increase below 2°C, the aspirational target for international negotiations, and considered the threshold for “dangerous” climate change…more