r/science Oct 17 '21

Global urban population exposure to extreme heat Environment


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u/Astrobubbers Oct 18 '21

Imagine what the wild animals are going through


u/unelaboratedov Oct 19 '21

I'm sorry, theres an article you're thinking of about how we can stop this, right?


u/happierinverted Oct 17 '21

Is this why population levels are dropping off a cliff and global life expectancy is crashing?


u/burtzev Oct 18 '21

No. It certainly contributes to excess deaths, but it is far from being the major factor. In any case global population 'levels' are not declining in most of the world. The present rate of growth is 1.05%, a considerable decline from 2.09% in the late 60s but still positive. What IS declining is the rate of growth. Any growth at all obviously leads to increased rather than decreased population. See here for further discussion. The wiki linked here also has a table of the exceptions, countries where population actually has declined and some discussion of the reasons for this. The one factor common to all these cases is a falling birth rate rather han a growing death rate.

What has declined is life expectancy, especially in the USA. Here's a comparison amongst OECD countries. This continues a long standing trend of lowered life expectancy in the USA as compared to other countries. The large American drop, however, is connected to the pandemic as it is elsewhere, and life expectancy there may level out after the emergency has passed. Don't expect any large gains though. The chronic problems that put the USA at the bottom of the OECD life expectancy list are still there.

Life expectancy probably has declined globally just as it generally has in the developed countries of the OECD, once more because of the effects of the pandemic.

So, summing up deaths from heat are a part of death rates, but the gross population numbers aren't decreasing. In terms of life expectancy once more they contribute, but pandemic factors have been more important.


u/happierinverted Oct 18 '21

I was being ironic. The graph was attempting to show that climate change was at some level affecting the success of the human species and posing an existential risk, but looking objectively at the top line numbers it simply isn’t.


u/BeNice_777 Oct 18 '21

Global exposure to urban heat islands isn't a measure of extreme heat, its a measure of urban population increase.

Correlation doesn't imply causation.



u/Swissaliciouse Oct 18 '21

Read first before offering your opinion:

Population growth (Fig. 1B) and total urban warming (Fig. 1C) contributed 66% (1.5 billion person-days/yr−1) and 34% (0.7 billion person-days/yr−1) to the annual rate of increase in exposure, respectively.