Scientist explains how Earth shows its anger

Angry Weather: Heat Waves, Floods, Storms and The New Science of Climate Change

By Friederike Otto

Greystone Books

An exciting new volume from Vancouver's Greystone Books introduces an important new development in climate science.

Although the broad strokes of climate-change theory are clear and have stood up well to peer review and debate, until the emergence of this new approach of weather attribution, it was difficult for scientists to connect the dots and show the impacts of global climate change on specific extreme weather events. This gap in the explanatory power of the science has been exploited by fossil-fuel industry apologists and some politicians to cast doubt on the need for decarbonizing the economy before it is too late.

Friederike Otto and her colleagues at Oxford's Environmental Change Institute have developed an approach they believe addresses this issue.

Using global weather observations extending back into the historical record and generated in real time by weather stations and satellites plus deploying sophisticated computer modelling methods, they now say they can determine whether or not a specific storm, flood or heat spell has been caused by human-created climate change, and where climate change has been a factor they can quantify the scope of its impact.

This elegant new branch of climate science depends upon massive networks of computers linked together to process dizzying volumes of data.

By comparing actual extreme events to a baseline computer model that portrays what Earth's climate system would look like absent any human-caused emissions, Otto and her colleagues can calculate, for example, that human-caused climate change made the disastrous rainfall over Houston, Texas associated with 2017's hurricane Harvey three times more likely to occur.

Of the 190 extreme weather events Otto's team has studied so far, climate change has made about two-thirds of them more intense or more likely. (This underscores an important point that Otto makes,: Not every extreme weather event can be attributed to climate change. Most, it looks like, but not all.)

These findings have profound implications for public policy and planning, and will lead to even more useful research in the future. Otto and her colleagues, like the Cassandra of Greek myth, have some ability to see the future. For all our sakes, let's hope they don't share Cassandra's curse of never being believed.