Mudelsee, M., Borngen, M., Tetzlaff, G. and Grunewald, U. 2003. No upward trends in the occurrence of extreme floods in central Europe. Nature 425: 166-169.
According to John Hooper's 14 August 2002 article in The Guardian, in the midst of that year's massive flooding in Europe, Gallus Cadonau (the managing director of the Swiss Greina Foundation) called for a punitive tariff on U.S. imports to force cooperation on greenhouse gas emissions, claiming that the flooding "definitely ha[d] to do with global warming" and stating that "we must change something now." He was joined in this sentiment by Germany's environment minister, Jurgen Trittin, who implied much the same thing when he said "if we don't want this development to get worse, then we must continue with the consistent reduction of environmentally harmful greenhouse gasses." A thorough analysis of historical flood accounts and more recent river-flow data, however, suggests something very different.
What was done
Mudelsee et al. analyzed historical documents stretching from the 11th century to 1850 and subsequent water stage and daily runoff records from then until 2002 pertaining to two of the largest rivers in central Europe, the Elbe and Oder rivers, seeking to determine trends in flood occurrence over the past thousand years.
What was learned
The team of German scientists report that "for the past 80 to 150 years" -- which climate alarmists typically describe as a period of unprecedented global warming -- "we find a decrease in winter flood occurrence in both rivers, while summer floods show no trend, consistent with trends in extreme precipitation occurrence."
What it means
The strident claims of the world's Cadonaus and Trittins clearly don't stand up to scrutiny when compared with reality. As the world has recovered from the global chill of the Little Ice Age, flooding of the Elbe and Oder rivers has not materially changed in summer and has actually decreased in winter. Blaming anthropogenic CO2 emissions for the European flooding of 2002 must thus have been a political ploy, for it was surely not a reasoned deduction based on scientific evidence.
Reviewed 8 October 2003