How serious is global warming of a few degrees? Couldn warming be beneficial?
A warming of 1°F over the past century and a further 2-6°F over the 21st century, as projected by the IPCC, may appear minor compared to short-term weather changes from night to day and winter to summer. But in global climate terms, a warming at this rate would be much larger and faster than any of the climatic changes over the past 10,000 years. Global temperatures during the last ice age (about 20,000 years ago) were ‘only’ 9°F cooler than today, but that was enough to allow massive ice sheets to reach as far south as the Great Lakes and New York City. The warming that humans are causing will change Earth’s climate in the opposite direction, but tens or possibly a hundred times faster than natural rates of climate change. Warming of a few degrees would lead to more frequent droughts and heat waves, cause greater rainfall, and possibly change the strength of storms. It is possible that some areas would benefit from global warming even as other areas were harmed. Certain farming areas,
