Sleepless Nights: Faster nighttime warming due to climate change is impacting sleep quality across the globe


The purpose of this analysis is to analyze nighttime temperatures in the context of a warming global climate, with a focus on summer (December-February in the Southern Hemisphere, June-August in the Northern Hemisphere). To do this, we calculated the number of days where the nighttime temperature — the minimum temperature — exceeded 18°, 20°C, and 25°C. We also used the Climate Shift Index daily attribution system to quantify how climate change has influenced the number of uncomfortably hot nights. The Climate Shift Index system uses observed patterns of warming and 24 global climate models to estimate the nighttime temperature that would have occurred in a counterfactual climate without human-caused 1climate change. The difference between the observed number and the counterfactual number gives the number of uncomfortable nights added by climate change. For this analysis, we focus on the average over the last 10 years — 2014-2023.

VIEW REPORT>