, temperatures were 20 – 30 percent
higher than the seasonal average over much of Europe, from Spain to the
Czech Republic. French grapegrowing records — which contain histori
cal climate data — indicated that the event had no equal since 1370.
The odds of such a heat wave happening by chance, based on climate
trends from 1864 to 2002, were about one in ten million. “The 2003
anomaly can only be accounted for by a combination of global warming
and natural variability,” wrote Kevin Trenberth of the National Center
for Atmospheric Research.
What if a heat wave like the