The first quarter of 2016 has seen climate records smashed, with the northern hemisphere briefly tipping over the two degrees of warming danger level. Climate scientists have already warned us that polar and glacial ice is melting faster than IPCC models anticipated. The resulting sea level rise is now expected to occur much more rapidly, with levels not expected until 2100 being reached as soon as 2050.
As if all of this bad news wasn’t enough, scientists at Yale University have added further data that suggests that even our worst case scenarios for climate change may be underestimates. This is because the models overestimate the volume of ice within clouds. Just like sea ice, ice in clouds reflects heat out to space. The more ice there is in the clouds, the greater the effect. So having the correct amount of cloud ice in climate models has a large impact on their forecasts. Trude Storelvmo, a Yale assistant professor of geology and geophysics explains:
“We saw that all of the models started with far too much ice. When we ran our own simulations, which were designed to better match what we found in satellite observations, we came up with more warming.”
What this means is that IPCC projections that put the likely temperature rise between 2 and 4.7 degrees should actually be projecting warming of 5 to 5.3 degrees. If correct, the implications are nothing short of catastrophe – “It goes to everything from sea level rise to more frequent and extreme droughts and floods,” said Ivy Tan, lead author of the study.