Editing Heat wave (section)

=== Mortality ===
[[File:NWS HeatRisk Categories.jpg|thumb|The National Weather Service risk categories for ''NWS HeatRisk'']]
{{excerpt|Effects of climate change on human health#Heat-related mortality|paragraphs=1-2|file=no}}

==== Underreporting of fatalities ====
The number of heat fatalities is probably highly underreported. This is due to a lack of reports and to misreporting.<ref name="heat epidemiology">{{cite journal |last=Basu |first=Rupa |author2=Jonathan M. Samet |year=2002 |title=Relation between Elevated Ambient Temperature and Mortality: A Review of the Epidemiologic Evidence |journal=[[Epidemiologic Reviews]] |volume=24 |issue=2 |pages=190–202 |doi=10.1093/epirev/mxf007 |pmid=12762092 |doi-access=free}}</ref> When considering heat-related illnesses as well, actual death tolls from extreme heat may be six times higher than official figures. This is based on studies of California<ref>{{Cite web |title=Heat waves are far deadlier than we think. How California neglects this climate threat |url=https://www.latimes.com/projects/california-extreme-heat-deaths-show-climate-change-risks/ |access-date=2022-09-04 |website=Los Angeles Times |date=7 October 2021 |language=en}}</ref> and Japan.<ref>{{Cite journal |last1=Fujibe |first1=Fumiaki |last2=Matsumoto |first2=Jun |date=2021 |title=Estimation of Excess Deaths during Hot Summers in Japan |url=https://www.jstage.jst.go.jp/article/sola/17/0/17_2021-038/_article/-char/ja |journal=Scientific Online Letters on the Atmosphere |volume=17 |pages=220–223 |bibcode=2021SOLA...17..220F |doi=10.2151/sola.2021-038 |s2cid=241577645 |doi-access=free}}</ref>

Part of the mortality during a heat wave may be due to short-term forward [[mortality displacement]]. In some heat waves there is a decrease in overall mortality in the weeks after a heat wave. These compensatory reductions in mortality suggest that heat affects people who would have died anyway, and brings their deaths forward.<ref name="pmid11401757">{{cite journal |last1=Huynen |first1=Maud M. T. E |last2=Martens |first2=Pim |last3=Schram |first3=Dieneke |last4=Weijenberg |first4=Matty P |last5=Kunst |first5=Anton E |year=2001 |title=The Impact of Heat Waves and Cold Spells on Mortality Rates in the Dutch Population |journal=Environmental Health Perspectives |volume=109 |issue=5 |pages=463–70 |doi=10.2307/3454704 |jstor=3454704 |pmc=1240305 |pmid=11401757}}</ref>

Social institutions and structures influence the effects of risks. This factor can also help explain the underreporting of heat waves as a health risk. The deadly [[2003 European heat wave#France|French heat wave]] in 2003 showed that heat wave dangers result from a combination of natural and social factors.<ref>{{cite journal |last1=Poumadère |first1=M. |last2=Mays |first2=C. |last3=Le Mer |first3=S. |last4=Blong |first4=R. |year=2005 |title=The 2003 Heat Wave in France: Dangerous Climate Change Here and Now |url=http://www.coe.int/t/dg4/majorhazards/activites/murcia_26-27oct2009/heatwave2003_poumadere2005.pdf |journal=Risk Analysis |volume=25 |issue=6 |pages=1483–1494 |citeseerx=10.1.1.577.825 |doi=10.1111/j.1539-6924.2005.00694.x |pmid=16506977 |bibcode=2005RiskA..25.1483P |s2cid=25784074}}</ref> Social invisibility is one such factor. Heat-related deaths can occur indoors, for instance among elderly people living alone. In these cases it can be challenging to assign heat as a contributing factor.<ref>{{Cite journal |last=Ro |first=Christine |date=2022-09-01 |title=Can Japan really reach "zero deaths" from heat stroke? |url=https://www.bmj.com/content/378/bmj.o2107 |journal=BMJ |language=en |volume=378 |pages=o2107 |doi=10.1136/bmj.o2107 |issn=1756-1833 |s2cid=251954370 |doi-access=free|url-access=subscription }}</ref>