Heat, Health, and Habitats: Analyzing the Intersecting Risks of Climate and Demographic Shifts in Austrian Districts

TL;DR

This study analyzes how climate change and demographic aging in Austrian districts increase heat-related mortality, highlighting the importance of green infrastructure in mitigating health risks amidst rising temperatures and aging populations.

Contribution

It provides empirical evidence linking heat days, demographic factors, and mortality, and forecasts future risks while emphasizing the moderating role of green infrastructure.

Findings

Each additional hot day increases mortality by 2.4% per 1000 inhabitants.

Districts with more elderly populations face roughly double the heat-related mortality risk.

Green infrastructure significantly reduces the impact of heat on mortality.

Abstract

The impact of hot weather on health outcomes of a population is mediated by a variety of factors, including its age profile and local green infrastructure. The combination of warming due to climate change and demographic aging suggests that heat-related health outcomes will deteriorate in the coming decades. Here, we measure the relationship between weekly all-cause mortality and heat days in Austrian districts using a panel dataset covering $2015-2022$. An additional day reaching $30$ degrees is associated with a $2.4\%$ increase in mortality per $1000$ inhabitants during summer. This association is roughly doubled in districts with a two standard deviation above average share of the population over $65$. Using forecasts of hot days (RCP) and demographics in $2050$, we observe that districts will have elderly populations and hot days $2-5$ standard deviations above the current mean in just $25$ years. This predicts a drastic increase in heat-related mortality. At the same time, district green scores, measured using $10\times 10$ meter resolution satellite images of residential areas, significantly moderate the relationship between heat and mortality. Thus, although local policies likely cannot reverse warming or demographic trends, they can take measures to mediate the health consequences of these growing risks, which are highly heterogeneous across regions, even in Austria.