Extreme temperature events threaten vulnerable populations with limited access to shelter and water and/or with pre-existing health conditions. Funded by CPO’s Climate Observations and Monitoring Program (COM), a recent study helps improve understanding of what atmospheric circulation patterns are associated with extreme temperature events and therefore are likely to negatively impact human health and thermal comfort. It also provides a potential method for making this information useful on local scales.
The authors examined the relationship between atmospheric circulation and metrics related to extreme temperature events within five North American regions (Canada, North, West, Gulf, East) over the 1979 to 2016 period. They quantified extreme temperature events through a number of metrics, such as extreme dew point and excess cold factor, and identified atmospheric circulation patterns using daily sea-level pressure and 500 hPa geopotential height data from the North American Regional Reanalysis. Results show that while geopotential height is generally more strongly associated with extreme temperature events than sea level pressure, there is a lot of spatial variability in the strength of the relationship for many of the metrics. This variability is likely due to local geographical influence. The authors suggest that these findings may offer a potential path forward for inferring extreme temperature event potential on local scales, which could prove useful for investigating human health and thermal comfort under future climate scenarios.