“…societal change is sufficient to explain the increasing costs of disasters at the global level…”
We often hear of the wailing by climate activists and in the MSM about the huge cost numbers related to weather disasters, as if somehow these numbers are indicative of a trend linkable with ‘climate change’. For example, USA Today’s Doyle Rice reported in 2012 this headline:
The number of natural disasters per year has been rising dramatically on all continents since 1980, but the trend is steepest for North America where countries have been battered by hurricanes, tornadoes, floods, searing heat and drought, a new report says.
The study being released today by Munich Re, the world’s largest reinsurance firm, sees climate change driving the increase and predicts those influences will continue in years ahead, though a number of experts question that conclusion.
Atmospheric scientist Clifford Mass of the University of Washington also has a problem with Munich Re’s findings, saying that once the data are adjusted for population there is no recent upward trend in tornado or hurricane damages. Also, he adds that there is no evidence that global warming is causing more extreme weather in the USA.
Of course, any time an insurance company dabbles in science related to losses, you can be sure there’s a motivation other than pure science behind it. Shalini Mohleji and Roger Pielke Jr. thought this was worth examining to see if it such claims held up, and it turns out, they don’t.
The new paper:
Reconciliation of Trends in Global and Regional Economic Losses from Weather Events: 1980–2008
Shalini Mohleji and Roger Pielke Jr.
In recent years claims have been made in venues including the authoritative reports of the Intergovernmental Panel on Climate Change and in testimony before the US Congress that economic losses from weather events have been increasing beyond that which can be explained by societal change, based on loss data from the reinsurance industry and aggregated since 1980 at the global level. Such claims imply a contradiction with a large set of peer-reviewed studies focused on regional losses, typically over a much longer time period, which concludes that loss trends are explained entirely by societal change. To address this implied mismatch, we disaggregate global losses from a widely utilized reinsurance dataset into regional components and compare this disaggregation directly to the findings from the literature at the regional scale, most of which reach back much further in time. We find that global losses increased at a rate of $3.1 billion/year (2008 USD) from 1980–2008 and losses from North American, Asian, European, and Australian storms and floods account for 97% of the increase. In particular, North American storms, of which U.S. hurricane losses compose the bulk, account for 57% of global economic losses. Longer-term loss trends in these regions can be explained entirely by socioeconomic factors in each region such as increasing wealth, population growth, and increasing development in vulnerable areas. The remaining 3% of the global increase 1980 to 2008 is the result of losses for which regionally based studies have not yet been completed. On climate time scales, societal change is sufficient to explain the increasing costs of disasters at the global level and claims to the contrary are not supported by aggregate loss data from the reinsurance industry.