Claim 1: In Philidelphia, the optimal temperature seems to be about 80F; in 1960 when it got hotter, the death rate increased sharply. When temperatures dropped below freezing, it increased sharply. Death rates dropped in general due to better health care, but temperatures of 100F cause almost no excess deaths, while more people still die due to cold.
Source: Changing Heat-Related Mortality in the United States, and Decadal changes in heat-related human mortality in the eastern United States
Status of Claim: In general, this seems accurate (see Fig. 4 in the second link, and pay attention to the drop of the left-hand tails, heat related, but he should have mentioned the other cities studied. Also Figure 1 from the first paper:
Also, some quotes from 'conclusions': "In 4 of the 6 cities examined, mortality rates were less influenced by hot and humid summertime conditions in the 1980s and 1990s than they were in the 1960s–70s. " "The strength of relationships between daily weather conditions and mortality varies seasonally. In the US
and other countries, mortality is higher in winter than in summer (Langford & Bentham 1995, Donaldson & Keatinge 1997, Eurowinter Group 1997, Lerchl 1998), possibly because of increased transmission rates of infectious diseases such as influenza (Monto & Kioumehr 1975, Mandell et al. 1995). Though winter death rates are higher than those in summer, daily mortality is not typically highest on the coldest winter days. When examined on a daily (as opposed to a weekly, monthly, or seasonal) basis, mortality is more closely coupled to daily weather conditions in summer than in winter (Kalkstein & Davis 1989, Langford & Bentham 1995, Kalkstein & Greene 1997), although some significant winter relationships have also been found (Glass & Zack 1979, Larson 1990a,b, Gorjanc et al. 1999)."
No comments:
Post a Comment