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Temperature-related Human Mortality in Southern New England

Paper Reviewed
Weinberger, K.R., Kirwa, K., Eliot, M.N., Gold, J., Suh, H.H. and Wellenius, G.A. 2018. Projected changes in temperature-related morbidity and mortality in Southern New England. Epidemiology 29: 473-481.

Despite a plethora of data to the contrary (see the many reviews posted on our website under the heading Health Effects of Temperature), climate alarmists continue to claim that global warming will result in a net increase of human mortality, leading to a public health crisis just a few short decades from now.

The latest peer-reviewed study to debunk this false claim comes from Weinberger et al. (2018). Writing in the scientific journal Epidemiology, this team of six researchers investigated the relationship between daily mean temperature and mortality in Rhode Island over the period 1999-2011 using "distributed lag nonlinear models with an overdispersed Poisson distribution and a 21-day distributed lag function." The results of the analysis can be summed up in Figure 1(a) below.

As seen there, all-cause mortality rates are much higher below the minimum mortality temperature (MMT) of 22.5°C than they are above it. In fact, 12% of the deaths that occurred during the study period were attributable to deviations below the MMT, whereas a much smaller, 0.13% of deaths were attributable to temperatures above the MMT. Or, expressed as an attributable number, 1129 cold-related deaths occurred each year versus only 9 heat-related deaths, indicating that the number (or percent) of deaths caused by cold weather is over two orders of magnitude larger than those caused by hot weather!

Looking to the future, Weinberger et al. coupled temperature projections from the CMIP5 multimodel ensemble with their empirically-derived temperature/mortality relationship for Rhode Island to estimate changes in all-cause mortality in 2050 and 2090 based on the IPCC's RCP4.5 and RCP8.5 emission scenarios. The results of that exercise are illustrated in Figure 1(b). In short, the authors find that although heat-related deaths may increase, they are more than offset by declines in deaths from cold temperatures, resulting in a net savings of lives. In 2090, under RCP8.5, that net savings amounts to 218 fewer annual temperature-related deaths, compared to the present. And these favorable findings are not limited to Rhode Island, as Weinberger et al. repeated their analysis using data for Boston, Massachusetts, obtaining nearly identical results.

Clearly, cold temperatures are far more deadly to human health than warm temperatures; and a little global warming would help to save human lives.

Figure 1. Panel (A): Cumulative 21-day all-cause deaths relative to the location-specific minimum mortality temperature in Rhode Island. Panel (B): Bar plots of the predicted change (and 95% empirical confidence interval) in annual all-cause deaths attributable to deviations from the minimum mortality temperature in Rhode Island in 2045-2054 and 2085-2094 versus 2001-2010 under two IPCC emissions scenarios (RCP4.5 and RCP8.5). Source: Weinberger et al. (2018).

Posted 6 March 2019