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Deaths Due to Heat and Cold in US Cities
Davis, R.E., Knappenberger, P.C., Michaels, P.J. and Novicoff, W.M. 2004. Seasonality of climate-human mortality relationships in US cities and impacts of climate change. Climate Research 26: 61-76.

What was done
The authors examined the seasonality of mortality due to all causes using monthly data for 28 major US cities from 1964 to 1998, after which they calculated the consequences of a future 1C warming of the conglomerate of those cities.

What was learned
At all locations studied, Davis et al. report that "warmer months have significantly lower mortality rates than colder months." Hence, they calculate that "a uniform 1C warming results in a net mortality decline [our italics] of 2.65 deaths (per standard million) per metropolitan statistical area." Since the annual death rate of about 9500 deaths (per standard million) is so much larger, however, the "death benefits" of the warming are extremely small, i.e., a reduction in the annual number of deaths of less than 0.03%, which also pales in comparison to the nearly 20% reduction in annual mortality that has occurred as a consequence of technological advancements experienced between the 1960s/70s and the 1990s. Nevertheless, the result is extremely important for the specific people included in that particular 0.03% of the population!

What it means
The primary implication of Davis et al.'s findings, in their words, "is that the seasonal mortality pattern in US cities is largely independent of the climate and thus insensitive to climate fluctuations, including changes related to increasing greenhouse gases." Hence, it would appear that we in the developed world should be concentrating our efforts on fostering the same technological advancements we have experienced in all other parts of the planet, if we are truly serious about improving the quality - and length - of people's lives everywhere.

Reviewed 9 June 2004