The missing link in many discussions of global warming is how temperature rises affect the ecosystem as a whole, and subsequently our own society. The upcoming report promises to make those connections in frightening detail. Details include:
A 1 degree Celsius increase would means up to 1.7 billion extra people (equivalent to the entire population of the United States and China) will not have enough water, some infectious diseases and allergenic pollens rise, and some amphibians go extinct. The world’s food supply, especially in northern areas, could increase. This is the likely world outcome for the year 2020.
A further 1 degree rise means as many as 2 billion people could be without water and about 20 percent to 30 percent of the world’s species will be near extinction. More people start dying because of malnutrition, disease, heat waves, floods and droughts. This is the likely world outcome for the year 2050.
The report's authors give these findings a 90% level of confidence.
For those who think this is too far into the future to do anything about, it's time to start looking beyond the end of your own nose. I will personally be 44 and 74 at these intervals. On behalf of the under forty crowd I can assure you these problems are far to close to the horizon to continue to ignore.
However, there's good news. The report also stresses that these projections are based on a status quo of failing to curb greenhouse gases. There are "many turnoffs" along the highway to extinction and ultimately its up to us to take control of the wheel and head for one of them. Oceanographer James McCarthy summed it up even better,
“The worst stuff is not going to happen because we can’t be that stupid,” said Harvard University oceanographer James McCarthy, who was a top author of the 2001 version of this report. “Not that I think the projections aren’t that good, but because we can’t be that stupid.”