Bad weather ≠ Climate change.
Natural disasters around the world last year caused a record US$380 billion in economic losses. That’s more than twice the tally for 2010, and about $115 billion more than in the previous record year of 2005, according to a report from Munich Re, a reinsurance group in Germany. But other work emphasizes that it is too soon to blame the economic devastation on climate change.
Almost two-thirds of 2011’s exceptionally high costs are attributable to two disasters unrelated to climate and weather: the magnitude-9.0 earthquake and tsunami that hit Japan in March, and February’s comparatively small but unusually destructive magnitude-6.3 quake in New Zealand.
And the long-term rise in the costs of global disasters is probably due mainly to socio-eco- nomic changes, such as population growth and development in vulnerable regions. That conclusion is backed up by a forthcoming study — supported by Munich Re — by economists Fabian Barthel and Eric Neumayer at the London School of Economics. Their analysis of events worldwide between 1990 and 2008 concludes that “the accumulation of wealth in disaster-prone areas is and will always remain by far the most important driver of future economic disaster damage” (F. Barthel and E. Neumayer Climatic Change; in the press). Any major weather event hitting densely populated areas now causes huge losses because the value of the infrastructure has increased tremendously, they note, adding that if the 1926 Great Miami hurricane happened today, for example, it would cause much more damage than it did at the time…
But attempts to attribute specific events to global warming are in their infancy (see Nature 477, 148–149; 2011). “Disasters are a tempting image for advocacy, but the science is just not there to support strong claims,” says Roger Pielke Jr, a climate-policy researcher at the University of Colorado in Boulder. “We cannot yet attribute increasing dollar losses to human-caused climate change. Maybe we will one day, but not at present.”