This study has examined the key drivers that underlie year-to-year variations in excess winter deaths.
It has found that the association between the year-to-year variation in winter deaths and the number of cold days in a winter (those below 5C), has disappeared.
This link is apparent until the mid-1970s, but has diminished over recent decades to leave only the incidence of flu-like illnesses to explain any of the year-to-year variation in the winter death rate.
The authors cite improvements in housing and health care, higher incomes, and greater awareness of the risks of cold as reasons for the disappearance of this link.
These results show that whilst more deaths occur in winter, winter cold severity no longer predicts the numbers affected. They suggest that there is no evidence that excess winter deaths in England and Wales will fall if winters warm due to climate change.
This paper is interested in explaining the year to year variation in excess winter deaths – not the daily variation – and it is not suggesting that temperature does not play a role, if it didn’t there would not be an increase in deaths at this time of year. What it aims to demonstrate is that how harsh a winter is no longer predicts how many excess winter deaths there will be.
Up until now, it has been widely assumed by policymakers and health professionals that the harmful health impacts of anthropogenic climate change will be partially offset by a decline in excess winter deaths in temperate countries, as winters warm. This research has shown that is unlikely to be the case.
The paper is published in Nature Climate Change
Image courtesy of Ulf Bodin