The Australian Journal of General Practice (AJGP) promotes climate alarm
By Dr D Weston Allen (MBBS, FRACGP, Grad Dip Phys Med)
The August edition of the AJGP published a dreadful article authored by members of the Doctors for the Environment Australia (DEA), linking climate change to increased mortality from extreme weather events, bushfires, infectious diseases, water insecurity and reduced crop yields.1 The AJGP editor found the following letter “informative and interesting” but rejected it for publication.
The health impacts of climate change are mixed. Cold weather has more prolonged effects than heat2 and a much greater global mortality.3 Anthropogenic warming may be saving over a million lives annually.4 Cold-related deaths are projected to exceed heat-related deaths for some decades across most of the globe,5 even without adaptation and based on very improbable future emissions6 and climate models that run too hot.7
The latest scientific Assessment Report of the IPCC admits uncertainty regarding the climate sensitivity to CO2 and its impact on extreme weather events,8 whose global mortality has dramatically declined9 and normalised cost not increased.10
The diurnal temperature range (DTR) impacts health, increasing cardiac mortality by up to 3%,11 respiratory infections by 1-2%,12 childhood asthma by 6%13 and gastroenteritis by 3%14 per 1⁰C increase in DTR. By slowing the radiative cooling of Earth’s surface, greenhouse gases increase minimum temperatures more than maximums15 and thus reduce DTR and its adverse health impacts.16
Global crop yields keep reaching record levels,17 partly due to CO2 promoting growth18 and mitigating both heat-stress19 and drought.20 Protein content can be maintained by genotype selection21 and nitrogen fertilization.22 Global irrigation demand is expected to decline by about 17% by the 2080s due to the beneficial effects of CO2, shorter growing periods and regional precipitation increases,23 thus reducing the net global population at high risk of water stress.24
Energy policies impact human and planetary health.25 Promoting diesel to reduce CO2 emissions actually increased air pollution.26 Burning wood can be worse than burning coal.27 Intermittent renewables and the infrastructure required for baseload power are very resource intensive 28 and thus threaten biodiversity.29 Mining neodymium for wind turbine magnets produces radioactive waste.30 Nuclear power uses the least land/resources,31 has the lowest life-cycle emissions32 and fewest human deaths per unit of energy produced.33
Objectively evaluating all the evidence is essential. Whereas carbon dioxide is greening the planet and benefitting human health, climate action driven by ideology and vested interests may do far more harm than good.
1 Pendry CGA, Beaton L, Kneebone JA. General practice in the era of planetary health. AJGP 2020; 49 (8): 520-523
2 Braga ALF, Zanobetti A, Schwartz J. The effect of weather on respiratory and cardiovascular deaths in 12 U.S. cities. Environmental Health Perspectives 2002; 110: 859-863.
3 Gasparrini A, Guo Y, Hashizume M, et al. Mortality risk attributable to high and low ambient temperature: a multicountry observational study. The Lancet. 2015: 386 (9991): 369-375. DOI: 10.1016/S0140-6736(14)62114-0.
4 Bosello F, Roson R, Tol RSJ. Economy-wide Estimates of the Implications of Climate Change: Human Health. Ecological Economics 2006; 58(3): 579-91.
6 Hausfather Z, Peters GP. Emissions – the ‘business as usual’ story is misleading. Nature 2020; 577: 618-620 doi: 10.1038/d41586-020-00177-3
8 Bindoff NL, Stott PA, et al. Detection and Attribution of Climate Change: from Global to Regional. In: Climate Change 2013: The Physical Science Basis. Contribution of Working Group I to the Fifth Assessment Report of the Intergovernmental Panel on Climate Change [Stocker TF, Qin D et al. (eds.)] 2013: 871-924. Cambridge University Press, Cambridge, United Kingdom and New York, NY, USA
9 Goklany IM. Deaths and death rates due to extreme weather events: 1900-2008. Journal of American Physicians and Surgeons 2009; 14 (4): 102-109.
10 Pielke R. Economic ‘normalisation’ of disaster losses 1998-202: a literature review and assessment. Environmental Hazards 2020; DOI: 10.1080/17477891.2020.1800440
11 Cao J, Cheng Y, Zhao N, Song W, Jiang C, Chen R, Kan H. Diurnal temperature range is a risk factor for coronary heart disease death. Journal of Epidemiology 2009;19: 328-332.
12 Ge WZ, Xu F, Zhao ZH, Zhao JZ, Kan HD. Association between diurnal temperature range and respiratory tract infections. Biomedical and Environmental Sciences 2013; 26: 222-225.
13 Xu Z, Huang C, Su H, Turner LR, Qiao Z, Tong S. Diurnal temperature range and childhood asthma: a time-series study. Environmental Health 2013; 12: https://doi.org/10.1186/1476-069X-12-12
14 Xu Z, Huang C, Turner LR, Su H, Qiao Z, Tong S. Is diurnal temperature range a risk factor for childhood diarrhea? PLoS One 2013; 8(5):e64713. DOI: 10.1371/journal.pone.0064713.
15 Alexander LV, Zhang X, Peterson TC et al. Global observed changes in daily climate extremes of temperature and precipitation. J. Geophys. Res. Atmos. 2006; 111 (D5): 109-141 https://doi.org/10.1029/2005JD006290
16 Braganza K, Karoly DJ, Arblaster JM Diurnal temperature range as an index of global climate change during the twentieth century. Geophysical Research Letters 2004: 31 (13): 217-221 doi.org/10.1029/2004GL019998
18 Ainsworth EA, Long SP What have we learned from fifteen years of free-air CO2 enrichment FACE? A meta-analytic review of the responses of photosynthesis, canopy properties and plant production to rising CO2. New Phytologist 2005; 165:351-372.
19 Gutiérrez del Pozo D, Gutierrez E, Pérez P, et al. Acclimation to future atmospheric CO2 levels increases photochemical efficiency and mitigates photochemistry inhibition by warm temperatures in wheat under field conditions. Physiologia Plantarum 2009; 137 (1):86-100. DOI: 10.1111/j.1399-3054.2009.01256.x
20 Fleisher DH, Timlin DJ, Reddy VR. Elevated carbon dioxide and water stress effects on potato canopy gas exchange, water use and productivity. Agricultural and Forest Meteorology 2008; 148:1109-1122. https://doi.org/10.1016/j.agrformet.2008.02.007
21 De Costa J, Weerakoon WMW, Chinthaka KGR. et al. Genotypic variation in the response of rice (Oryza sativa) to increased atmospheric carbon dioxide and its physiological basis. Journal of Agronomy and Crop Science 2007; 193:117-130. DOI: 10.1111/j.1439-037X.2007.00255.x
22 Sultana H, Armstrong R, Suter H, et al. A short-term study of wheat grain protein response to post-anthesis foliar nitrogen application under elevated CO2 and supplementary irrigation. Journal of Cereal Science 2017; 75:135-137.
23 Konzmann M, Gerten D, Heinke J. Climate impacts on global irrigation requirements under 19 GCMs, simulated with a vegetation and hydrology model. Hydrological Sciences Journal 2013; 58 (1): 88-105.
24 Wiltshire A, et al. The importance of population, climate change and carbon dioxide plant physiological forcing in determining future global water stress. Global Environmental Change. 2013; 23 (5): 1083-1097.
25 ÓhAiseadha C, Quinn G, Connolly R, Connolly M, Soon W. Energy and Climate Policy-An Evaluation of Global Climate Change Expenditure 2011-2018. Energies 2020; (13) 4839. https://doi.org/10.3390/en13184839
26 Jenkins HW. Dieselgate is a political disaster. WSJ 2017; Feb. 14 https://www.wsj.com/articles/dieselgate-is-a-political-disaster-1487116586
27 Sterman JD, Siegel L, Rooney-Varga JN. Does replacing coal with wood lower CO2 emissions? Dynamic life cycle analysis of wood bioenergy. Environmental Research Letters 2018; 13 (1): 1-10
31 Cheng VKM and Hammond GP. Life-cycle energy densities and land-take requirements of various power generators: a UK perspective. Journal of the Energy Institute 2017; 90 (2): 201-213 https://doi.org/10.1016/j.joei.2016.02.003
32 Pehl M, Arvesen A, Humpenöder F. et al. Understanding future emissions from low-carbon power systems by integration of life-cycle assessment and integrated energy modelling. Nat Energy 2017; 2: 939-945 https://doi.org/10.1038/s41560-017-0032-9
33 Conca J. How deadly is your kilowatt? We rank the killer energy sources. Forbes 2012 https://www.forbes.com/sites/jamesconca/2012/06/10/energys-deathprint-a-price-always-paid/#17d1380d709b