We have delayed action for so long on handling climate change, we now can no longer can “will it happen?” Rather we have to ask “how bad will it be?” and “what can be done about it?” As our society thinks about what we should do to reduce our carbon pollution and the consequences of electing science-denying politicians, scientists are actively studying the pros and cons of various emission reductions.
Readers of this column have certainly heard about temperature targets such as 1.5°C or 2°C. These targets refer to allowable temperature increases over pre-industrial temperatures. If humans take action to hit a 1.5°C target, it means we are committed to keeping the human-caused global temperature rise to 1.5°C. Similarly for a 2°C target.
The lower the target, the smaller the climate change. The smaller the climate change, the better. But is it worth the effort to set lower targets? I mean, if 2°C is good enough, why take the trouble to keep temperatures within 1.5°C?
Fortunately, a new paper just out in the Philosophical Transactions of the Royal Society A asks this question. Specifically, they ask “How much larger are the impacts at 2°C compared to 1.5°C?” A follow-on question asked by the authors relates to what conditions occur at a particular level of warming, such as 2°C. This is a really important question because policymakers need to know what it will take to adapt to a 1.5°C world or a 2°C world. Read more