TCS Daily

Disaster Area

By Sallie Baliunas - October 18, 2002 12:00 AM

The United Nations Environmental Program (UNEP) just released a document that calls for reductions in carbon dioxide and other greenhouse gas emissions. No surprise there. But this time UNEP is saying such reductions are needed so that climate-disaster economic losses can be curtailed. The UNEP Finance Initiatives Climate Change Working Group report (October 8, 2002) tries to pin economic losses from natural disasters like storms and floods to the airs increase in human-made greenhouse gases which supposedly has caused a globally-averaged warming. This warming, the report alleges, should have spawned more - or more powerful - climate-related disasters like storms. Thus, UNEP asks developed economies like the United States to ration energy: ...[P]olicymakers should commit to clear GHG [greenhouse gas] emissions reduction targets via policies and measures consistent with the Kyoto Protocol that establish a clear value on carbon ... (p. 5, Module 1). How credible is UNEPs speculation on increased storm or other weather damage? Not very, since it includes several errors of fact and logic. The UNEP report says, Worldwide economic losses due to natural disasters appear to be doubling every ten years, and have reached almost $1 trillion [in U.S. 2001 dollars] over the past 15 years... If the current trends persist, the annual loss amounts will, within the next decade, come close to US$150 billion ... (p. 6, Module 1). UNEP shows a chart representing losses owing to Great natural catastrophes over the last 50 years. It is complete with a red line curving quickly upward demonstrating rapidly increasing losses (Figure 1, p. 6, Module 1). UNEP extends that red line into the future in order to reach its projection of US $150 billion annual losses within the next decade. But to have minimal credibility, a forecast trend needs to start by fitting the extant data. Mathematically, the UNEP fast-rising red line fails to fit the data. For example, 1994 and 1995 had the highest loss costs of any years in the 50-year record. Since then, losses have dropped. The rapidly-rising red line fails to reflect the post-1995 data, and that failure means the forecast trend for future high losses rests on all the confidence of quicksand. Next consider the relevance of the record of natural disasters to the airs increased carbon dioxide content. The extraordinary losses in 1994 (over $80 billion) and 1995 (over $167 billion) are dominated by the costs of the Northridge and Kobe earthquakes. Natural disasters like earthquakes and volcanic eruptions cannot be linked in any believable way to the airs increased concentration of greenhouse gases. Once non-weather events are discarded from the analysis, the upswept curve is even less justifiable. The possibility of grave economic losses in the future must be based on credible predictions of weather disasters, a task not considered in the UNEP report, since no one - including the United Nations Intergovernmental Panel on Climate Change - knows just how to do so. To examine the believability of the UNEP claim of increasing carbon-emission-related weather disasters, lets concentrate on the U.S. record of economic losses due to hurricanes, which are Americas costliest weather disasters. The record accounting for these losses is thorough and reaches back 100 years. Thats a period that can be split into two parts, before and after 1950 - that is, before and after the airs dramatic rise in carbon dioxide content. To make a fair comparison, the history of U.S. economic losses for hurricanes must be adjusted for socio-economic factors. To compare losses across decades, the values must be adjusted for increased population density in areas harmed by hurricanes, increased property values and wealth, and inflation. Once thats done, the normalized losses would have to show a rise related to the airs increased content in carbon dioxide, in parallel with a rise in storm severity or number of intense storms, as rated by measured meteorological parameters. Colorado and Florida researchers have provided the normalized losses for U.S. hurricane damage over the last 100 years. In terms of normalized losses, the most destructive year was 1926 with the Great Miami Hurricane. That hurricane would have caused $80-90 billion in losses had it occurred in the year 2000. The largest annual loss since 1926 occurred in 1992 with $40 billion in losses attributable primarily to Hurricane Andrew. Of the years with normalized losses totaling $20 billion or more, five of them occurred prior to 1950 (1900 including the unnamed Galveston Hurricane which killed over 6,000 people, the largest hurricane death toll in U.S. history - then 1915, 1926, 1938 and 1944). But after 1950 there are only two such years: 1954 (Hurricanes Carol and Hazel) and 1992 (Hurricane Andrew). Thus, the single largest normalized loss year for hurricanes, and five out of seven of the years in which losses exceed $20 billion, occurred before 1950 - before the major increase in the airs concentration of human-produced greenhouse gases. A linear trend of the normalized losses from most-costly hurricanes through the 20th century would slope downward, not upward, as UNEP contends. As for measured hurricane parameters, consider maximum intensity or maximum wind speed. If those parameters increase, it would likely yield greater economic losses. But the maximum wind speed of the strongest Atlantic hurricanes decreased from 1944 to 2000, the period studied by Florida and Colorado hurricane experts. Moreover, the most intense hurricanes come in three categories: Categories 3, 4 and 5 with a value of 5 indicating the most intense on the Saffir-Simpson Hurricane scale. But the annual total number of the most intense hurricanes over the Atlantic decreased since 1944. More precisely, U.S. hurricane experts concluded that [b]y far the biggest decade during the last active era was the 1940s, where five major hurricanes made landfall in Florida. This contrasts dramatically with the very low activity of the 1970s, 1980s and 1990s. Thus, there is no evidence that a greenhouse-gas enhanced atmosphere has produced either more intense or a greater number of severe hurricanes for the U.S or evidence of greater economic losses, in terms of normalized losses that fairly account for socio-economic changes. The UNEP report goes so far as to acknowledge that any recent upsurge in devastation is due not to climate-related factors, but to socio-economic factors: Although the steady increase in economic and insured losses is more a function of the concentration of economic development in vulnerable regions than climate change per se, it is clear that climate change will exacerbate these loss trends (p. 7, Module 1). Nonetheless, against the views of normative science, the UNEP report claims that, Scientific and technical reports present compelling evidence that human-induced climate change is upon us, and that its consequences could be devastating... (p. 8, Module 2). And then the report frankly reveals its anxiety about being sidetracked by recent U.S. corporate governance and accounting scandals or increasing concerns over the ability to fund burgeoning health and retirement programs. UNEP frets: ...there is clearly a risk that the climate change issue will not garner the level of attention necessary for any serious action to take place (p. 15, Module 2). The UNEP disaster claim may be expected but is scientifically unsupported.

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