Regional impact of global 2 Degrees C actually means far higher temperatures

Here is a good reason why we should be aspiring to meet the lower end of the Paris Agreement temperature goal of 1.5 degrees Celsius (2.7F).

In Paris diplomats adopted a temperature goal of "well below 2 degrees" of global warming and aspire to reach 1.5 degrees. This was a laudatory effort to bring climate policy into line with the climate science, which argues that beyond the 2 degree barrier we are likely to experience abrupt climate tipping points and enhanced climate feedbacks.

But 2 degrees Celsius average global temperature rise is a little misleading. "This climate target is abstract and invites misunderstanding,” says Sonia Seneviratne, Professor of Land-Climate Dynamics at ETH Zurich.

Seneviratne says that many people are likely to interpret two degrees globally as two degrees of warming in their region. They may then not push as hard for reducing CO2 emissions in their countries.

Major drop in solar activity will slow global warming minimally

Image: Potsdam Institute for Climate Impact Research

The latest buzz by global warming skeptics is the announcement of a Major drop in solar activity predicted at the American Astronomical Society’s Solar Physics Division conference. But the effect of a weakenng sun would hardly slow global warming according to modelling by climate scientists at the Potsdam Institute for Climate Impact Research. Their research shows global warming may be reduced by only about 0.3 degrees Celsius by 2100 by a new period of extensive solar inactivity.

You can read the best of the climate skeptic analysis and reporting of the press release and images and further analysis on Anthony Watt's Watt's Up With That blog. There is mainstream media coverage of this in National Geographic and the Sydney Morning Herald, Science Magazine or read other climate blogs on this at Climate Denial Crock of the Week and Climate Progress.

Albedo Feedback: Climate Models under estimate loss of reflectivity in the Arctic

Loss of reflectivity in the Arctic is double the estimate used in current state-of-art climate models according to new analysis of the Northern Hemisphere's "albedo feedback" over a 30-year period.

The albedo feedback is the change in the reflectivity of surfaces in a constant reinforcing feedback loop. In the Arctic snow and ice is highly reflective. Global warming has reduced sea ice exposing darker ocean and increased the size of dark melt pools on the Greenland ice sheet, which then increases the warming effect on ice in a positive feedback.

"The cryosphere isn't cooling the Earth as much as it did 30 years ago, and climate model simulations do not reproduce this recent effect," said Karen Shell, an Oregon State University atmospheric scientist and one of the authors of the study. "Though we don't necessarily attribute this to global warming, it is interesting to note that none of the climate models used for the 2007 International Panel on Climate Change report showed a decrease of this magnitude."