title: Global and regional changes in exposure to extreme heat and the relative contributions of climate and population change.
abstract: The frequency and intensity of extreme heat wave events have increased in the past several decades and are likely to continue to increase in the future under the influence of human-induced climate change. Exposure refers to people, property, systems, or other elements present in hazard zones that are thereby subject to potential losses. Exposure to extreme heat and changes therein are not just determined by climate changes but also population changes. Here we analyze output for three scenarios of greenhouse gas emissions and socio-economic growth to estimate future exposure change taking account of both climate and population factors. We find that for the higher emission scenario (RCP8.5-SSP3), the global exposure increases nearly 30-fold by 2100. The average exposure for Africa is over 118 times greater than it has been historically, while the exposure for Europe increases by only a factor of four. Importantly, in the absence of climate change, exposure is reduced by 75-95% globally and across all geographic regions, as compared with exposure under the high emission scenario. Under lower emission scenarios RCP4.5-SSP2 and RCP2.6-SSP1, the global exposure is reduced by 65% and 85% respectively, highlighting the efficacy of mitigation efforts in reducing exposure to extreme heat.
authors.affiliation: State Key Laboratory of Earth Surface Processes and Resource Ecology, Beijing Normal University, Beijing, 100875, China.|Department of Earth and Environment, Boston University, Boston, 02115, USA.|Academy of Disaster Reduction and Emergency Management, Beijing Normal University, Beijing, 100875, China.
authors.forename: Zhao
authors.initials: Z
authors.lastname: Liu
authors.affiliation: Department of Earth and Environment, Boston University, Boston, 02115, USA.
authors.forename: Bruce
authors.initials: B
authors.lastname: Anderson
authors.affiliation: School of Geography, State Key Laboratory of Remote Sensing Science, Beijing Normal University, Beijing, 100875, China.
authors.forename: Kai
authors.initials: K
authors.lastname: Yan
authors.affiliation: School of Geography, State Key Laboratory of Remote Sensing Science, Beijing Normal University, Beijing, 100875, China.
authors.forename: Weihua
authors.initials: W
authors.lastname: Dong
authors.affiliation: School of Geography, State Key Laboratory of Remote Sensing Science, Beijing Normal University, Beijing, 100875, China.
authors.forename: Hua
authors.initials: H
authors.lastname: Liao
authors.affiliation: State Key Laboratory of Earth Surface Processes and Resource Ecology, Beijing Normal University, Beijing, 100875, China.|Academy of Disaster Reduction and Emergency Management, Beijing Normal University, Beijing, 100875, China.
authors.forename: Peijun
authors.initials: P
authors.lastname: Shi
mesh_terms: D000349:Africa; D057231:Climate Change; D003198:Computer Simulation; D017753:Ecosystem; D004781:Environmental Exposure; D005060:Europe; D055874:Extreme Heat; D006801:Humans; D011157:Population Dynamics