MIT Greenhouse Gamble: No-Policy Case (left) where emissions are not limited, and Policy Case (right) where carbon emissions are limited, indicate likelihood of future temperature increases. The size of a pie slice indicates likelihood.
Called
The Greenhouse Gamble, the project calculates the odds of temperature increases by 2100 based on what we do, or don't do, to limit carbon emissions. The project began in 2003, and updated projections released this year see significantly warmer temperatures for earth in the absence of stringent emissions reductions.
If we do nothing, odds are 1 in 11 (9 percent) that average temperatures will rise by 7 degrees C. by 2100. (That's 12.6 degrees F.) So far, we are doing less than nothing as global carbon emissions keep rising at record rates beyond any previous expectation. As we keep on this path the chance is less than 1 in 100 (1 percent) that temperatures will rise less than 3 degrees C. (5.4 degrees F.) Is it getting warm in here?
The longer we wait to cut back carbon emissions the higher future temperatures are likely to get. The
2002 gamble showed that 5 degrees C. was the previous ceiling if emissions continued unabated.
So now the 2009 gamble tells us the future is going to be warmer than we thought it might be.
Climatologist Stephen Schneider of Stanford uses a
fire insurance analogy to help people understand the risk from rising temperatures: Most people have fire insurance on their homes even though few have ever had fires. Reduced carbon emissions would be the equivalent of fire insurance for the earth.
We are looking at odds of 1 in 11 (nine percent) that earth (our house) is going to heat up more than 12 degrees F. by 2100. Essentially the earth we know is going to burn down, we're doing nothing to insure ourselves against this, and at the rate carbon emissions are rising we are in effect throwing gasoline on the fire.