Estimating human health damage factors related to CO2 emissions by considering updated climate-related relative risks
Frequent updates on the evaluation of health risks associated with climate change are made. The existing health damage factors associated with CO2 emission are based on the findings compiled by the 2004 World Health Organization (WHO) report. An updated version of the 2014 WHO report is now available, and based on its contents, this study aimed to estimate relative risk (RR) and calculate health damage factors for each shared socioeconomic pathway (SSP) scenario.
Damage factors (DALY/kg-CO2) were calculated as increment of temperature (°C/kg) multiplied by increment of RR per °C, base mortality rate without climate change (−), population, and disability-adjusted life year (DALY) per case of death. RRs and base mortality rates were calculated for each SSP scenario. RRs by SSP scenario were estimated based on the RRs of three economic growth scenarios (high growth, base case, and low growth), which were calculated based on the results of the 2014 WHO report. Base mortality rates for each SSP scenario were calculated based on its relationship with gross domestic product per capita.
Results and discussion
In relation to undernutrition, diarrhea, malaria, dengue, heat stress, and coastal floods, the health damage factors (DALY/kg) for the SSP1, SSP2, and SSP3 scenarios were 1.3 × 10−6, 1.5 × 10−6, and 2.0 × 10−6, respectively. During a 100-year evaluation period, the damage factors obtained in the current study were 3–5 times higher than those in previous studies mainly because relative risk per degree Celsius (RR/°C) in the 2014 WHO report was larger than that in the 2004 WHO report. When RRs were estimated for each SSP scenario, the RR of SSP3 (with higher base mortality) was relatively low, particularly in case of undernutrition. Therefore, differences in the damage factors between the scenarios were more likely smaller than before when a single RR was used.
New health damage factors for the SSP1, SSP2, and SSP3 scenarios were estimated using an updated RR calculated based on the 2014 WHO report. These factors can be further updated in the future using RRs obtained from upcoming researches on climate-related health impact that were based on SSP scenarios.
KeywordsClimate change Disability adjusted life years Human health damage Life cycle impact assessment Relative risk Shared socioeconomic pathway scenario
We thank Dr. Sophie Bonjour and Dr. De. Colin Mathers for providing us the data of base mortality and population. This study was supported by the Environmental Research and Technology Development Fund (S-14) of the Ministry of the Environment of Japan.
- Ezzati M, Lopez AD, Rodgers A, Murray CJL (2004) Comparative quantification of health risks. Global and regional burden of diseases attributable to selected major risk factors. World Health Organization, GenevaGoogle Scholar
- Hales S, Kovats RS, Lloyd S, Campbell-Lendrum D (eds) (2014) Quantitative risk assessment of the effects of climate change on selected causes of death, 2030s and 2050s. World Health Organization (WHO), GenevaGoogle Scholar
- International Institute for Applied Systems Analysis (IIASA) (2016) SSP Database - Version 1.1. https://tntcat.iiasa.ac.at/SspDb. Accessed 19 May 2017
- IPCC (2007) Climate Change 2007: The Physical Science Basis. In: Solomon S, Qin D, Manning M, Chen Z, Marquis M, Averyt KB, Tignor M, Miller HL (eds) Contribution of Working Group I to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change. Cambridge University Press, Cambridge 996 ppGoogle Scholar
- IPCC (2013) Climate Change 2013: The Physical Science Basis. In: Stocker TF, Qin D, Plattner G-K, Tignor M, Allen SK, Boschung J, Nauels A, Xia Y, Bex V, Midgley PM (eds) Contribution of Working Group I to the Fifth Assessment Report of the Intergovernmental Panel on Climate Change. Cambridge University Press, Cambridge, 1535 pp. https://doi.org/10.1017/CBO9781107415324 CrossRefGoogle Scholar
- IPCC (2014) In: Field CB, Barros VR, Dokken DJ, Mach KJ, Mastrandrea MD, Bilir TE, Chatterjee M, Ebi KL, Estrada YO, Genova RC, Girma B, Kissel ES, Levy AN, MacCracken S, Mastrandrea PR, White LL (eds) Climate Change 2014: Impacts, adaptation, and vulnerability. Summaries, frequently asked questions, and cross-chapter boxes. A contribution of working group II to the fifth assessment report of the intergovernmental panel on climate change. World Meteorological Organization, Geneva 190 ppGoogle Scholar
- Mathers CD, Loncar D (2005) Updated projections of global mortality and burden of disease, 2002–2030: data sources, methods and results. WHO, GenevaGoogle Scholar
- Murray CJL (1996) Rethinking DALYs. In: Murray CJL, Lopez AD (eds) The global burden of disease, Global Burden of Disease and Injury Series, vol 1. Harvard University Press, Cambridge, pp 1–98Google Scholar
- United Nations (UN), Department of Economic and Social Affairs, Population Division (2011). World population prospects: the 2010 revision, volume I: comprehensive tables. ST/ESA/SER.A/313Google Scholar
- WHO (2017a) CAUSE-SPECIFIC MORTALITY http://www.who.int/healthinfo/global_burden_disease/estimates/en/index1.html. Accessed 10 May 2017
- WHO (2017b) DISEASE BURDEN http://www.who.int/healthinfo/global_burden_disease/estimates/en/index2.html. Accessed 10 May 2017
- Wigley TML (2008) MAGICC/SCENGEN 5.3: USER MANUAL (version 2). http://www.cgd.ucar.edu/cas/wigley/magicc/UserMan5.3.v2.pdf. Accessed 8 April 2017