However, it’s not just high and low temperatures that matter. How many degrees the temperature swings within a day – the daily temperature variation – itself poses health risks.

Global warming has so far seen a gradual rise in average temperatures. But that may change, with extreme variations. And poor countries could bear the brunt of it.

The map shows the variation in temperature differences between ground level and above canopy level (ground level always cooler) on the South American continent. The map is based on actual data ...

We mapped daily temperature variations at the neighborhood scale across the U.S. to get a better picture of where these temperature swings are highest and who is most affected.