The pull of the “front-page thought” and the eagerness of climate campaigners to jog the public have sometimes created a tendency to tie mounting losses from weather-related disasters to human-driven global warming.
But finding a statistically robust link between such disasters and the building human climate influence remains a daunting task. A new analysis of nearly two dozen papers assessing trends in disaster losses in light of climate change finds no convincing link. The author concludes that, so far, the rise in disaster losses is mainly a function of more investments getting in harm’s way as communities in places vulnerable to natural hazards grow.
The paper — “Have disaster losses increased due to anthropogenic climate change?” — is in press in the Bulletin of the American Meteorological Society. It was written by Laurens M. Bouwer, a researcher at Vrije University in Amsterdam focused on climate and water resources (and a lead author of a chapter in the 2001 assessment from the Intergovernmental Panel on Climate Change). You can read more about the paper at the blog of Roger Pielke, Jr., which drew my attention to this work.
Here’s the summary and a link to the full paper:
The increasing impact of natural disasters over recent decades has been well documented, especially the direct economic losses and losses that were insured. Claims are made by some that climate change has caused more losses, but others assert that increasing exposure due to population and economic growth has been a much more important driver. Ambiguity exists today, as the causal link between climate change and disaster losses has not been addressed in a systematic manner by major scientific assessments. Here I present a review and analysis of recent quantitative studies on past increases in weather disaster losses and the role of anthropogenic climate change. Analyses show that although economic losses from weather related hazards have increased, anthropogenic climate change so far did not have a significant impact on losses from natural disasters. The observed loss increase is caused primarily by increasing exposure and value of capital at risk. This finding is of direct importance for studies on impacts from extreme weather and for disaster policy. (Read the rest.)
The bottom line? Regardless of what happens due to global warming, on a crowding, urbanizing planet, increased exposure to, and losses from, nature’s hard knocks are a sure thing if people keep settling in harm’s way.
None of this negates the importance of moving to limit emissions of long-lived greenhouse gases; the analysis just reinforces the reality that while that effort proceeds, there’s plenty of other work to do, as well, if humanity desires a relatively smooth journey in this century (as was recently stressed by Robert Verchick here).