How much warming does new IPCC report see in our future?

Perhaps the most publicly visible products from the Intergovernmental Panel on Climate Change (IPCC) reports are the projections of future climate change. Aside from the evidence that humans are responsible for recent global warming, the projections are what make the nightly news. Maybe that’s why those projections are also the target of so much argument and, all too often, misrepresentation. When it comes to climate change, the globe isn’t the only thing that gets heated.

With a final draft of the physical science portion of the next IPCC report released a couple weeks ago, it’s worth taking a little time to examine what, exactly, the new projections entail.

Projections 101

What the heck is a projection anyway? A psychic might claim to predict the future, your local TV meteorologist forecasts the weekend weather. But climate model projections are different things entirely. First, since future climate change depends on many types of human-caused emissions and landscape changes, several projections are generated based on a range of potential changes. The relevance of a projection depends on how closely the emissions scenario it relies on matches what actually takes place.