title: What effect will a few degrees of climate change have on human heat balance? Implications for human activity.
abstract: While many factors affecting human health that will alter with climate change are being discussed, there has been no discussion about how a warmer future will affect man's thermoregulation. Using historical climate data for an Australian city and projections for Australia's climate in 2070, we address the issue using heat balance modelling for humans engaged in various levels of activity from rest to manual labour. We first validate two heat balance models against empirical data and then use the models to predict the number of days at present and in 2070 that (1) sweating will be required to attain heat balance, (2) heat balance will not be possible and hyperthermia will develop, and (3) body temperature will increase by 2.5°C in less than 2 h, which we term "dangerous days". The modelling is applied to people in an unacclimatised and an acclimatised state. The modelling shows that, for unacclimatised people, outdoor activity will not be possible on 33-45 days per year, compared to 4-6 days per year at present. For acclimatised people the situation is less dire but leisure activity like golf will be not be possible on 5-14 days per year compared to 1 day in 5 years at present, and manual labour will be dangerous to perform on 15-26 days per year compared to 1 day per year at present. It is obvious that climate change will have important consequences for leisure, economic activity, and health in Australia.
authors.affiliation: School of Biomedical, Biomolecular, and Chemical Science, The University of Western Australia, Physiology M311, 35 Stirling Highway, Crawley, WA, 6009, Australia. shanem@cyllene.uwa.edu.au
authors.forename: Shane K
authors.initials: SK
authors.lastname: Maloney
authors.forename: Cecil F
authors.initials: CF
authors.lastname: Forbes
mesh_terms: D000064:Acclimatization / Q000502:physiology*; D001315:Australia; D057231:Climate Change; D003198:Computer Simulation; D006801:Humans; D007899:Leisure Activities; D008954:Models, Biological; D009043:Motor Activity / Q000502:physiology*; D013546:Sweating / Q000502:physiology*; D013696:Temperature
references.citation: Med Sci Sports Exerc. 1996 Dec;28(12):i-x
references.pmid: 8970149
references.citation: Am J Physiol. 1990 Mar;258(3 Pt 1):E399-412
references.pmid: 2180312
references.citation: Fed Proc. 1973 May;32(5):1598-601
references.pmid: 4705206
references.citation: Science. 1916 May 19;43(1116):716-9
references.pmid: 17773961
references.citation: J Appl Physiol (1985). 1999 Mar;86(3):1032-9
references.pmid: 10066720
references.citation: Exp Physiol. 2004 Nov;89(6):691-700
references.pmid: 15328309
references.citation: J Hyg (Lond). 1935 May;35(2):255-61
references.pmid: 20475276
references.citation: Int J Epidemiol. 2008 Apr;37(2):309-17
references.pmid: 18194962
references.citation: Ind Health. 2006 Jul;44(3):388-98
references.pmid: 16922182
references.citation: Arch Sci Physiol (Paris). 1973;27(3):271-84
references.pmid: 4807385
references.citation: Acta Physiol Scand. 1996 Dec;158(4):365-75
references.pmid: 8971258
references.citation: J Sci Med Sport. 2008 Jan;11(1):40-7
references.pmid: 17553744
references.citation: Science. 2009 Feb 20;323(5917):1020-1
references.pmid: 19229026
references.citation: J Physiol. 1973 Apr;230(2):255-71
references.pmid: 4708895
references.citation: J Appl Physiol Respir Environ Exerc Physiol. 1983 Apr;54(4):972-7
references.pmid: 6853304
references.citation: J Appl Physiol. 1969 Jan;26(1):111-8
references.pmid: 5762862
references.citation: J Physiol. 1956 Jun 28;132(3):559-76
references.pmid: 13332594
references.citation: Lancet. 2006 Mar 11;367(9513):859-69
references.pmid: 16530580
references.citation: Ergonomics. 1996 Feb;39(2):225-31
references.pmid: 8851527
references.citation: Med J Aust. 2003 May 5;178(9):427-32
references.pmid: 12720507
references.citation: Crit Care. 2004 Feb;8(1):1-2
references.pmid: 14975035
references.citation: JAMA. 1984 Sep 7;252(9):1165-9
references.pmid: 6471340
references.citation: J Appl Physiol Respir Environ Exerc Physiol. 1979 Mar;46(3):522-8
references.pmid: 438022
references.citation: J Appl Physiol. 1976 Jul;41(1):71-6
references.pmid: 972135
references.citation: Int J Public Health. 2010 Apr;55(2):113-21
references.pmid: 19771392
references.citation: J Appl Physiol (1985). 2002 Jun;92(6):2256-63
references.pmid: 12015334
references.citation: Proc Natl Acad Sci U S A. 2008 Jul 15;105(28):9841-6
references.pmid: 18626008
references.citation: J Appl Physiol Respir Environ Exerc Physiol. 1980 Aug;49(2):254-61
references.pmid: 7400008
references.citation: Science. 2000 Sep 22;289(5487):2068-74
references.pmid: 11000103
references.citation: Eur J Appl Physiol Occup Physiol. 1986;55(3):281-9
references.pmid: 3732255
references.citation: J Hyg (Lond). 1933 Aug;33(3):330-48
references.pmid: 20475187
references.citation: Age Ageing. 1993 Jan;22(1):S26-33
references.pmid: 8438652
references.citation: Fed Proc. 1963 May-Jun;22:801-9
references.pmid: 13993226
references.citation: Fed Proc. 1973 May;32(5):1602-6
references.pmid: 4705207
references.citation: Am J Forensic Med Pathol. 2001 Jun;22(2):196-9
references.pmid: 11394759
references.citation: Ind Health. 2006 Jul;44(3):331-44
references.pmid: 16922177
references.citation: Eur J Appl Physiol Occup Physiol. 1985;54(5):480-7
references.pmid: 4085475
references.citation: Am J Public Health. 2002 May;92(5):830-3
references.pmid: 11988455
references.citation: J Sci Med Sport. 2008 Jan;11(1):20-32
references.pmid: 17765661
references.citation: Am J Public Health (N Y). 1924 Nov;14(11):978-9
references.pmid: 18011371