Climate change and population ageing in China – an emerging public health perspective

Climate change and population ageing in China – an emerging public health perspective

by Dr Ying Zhang
CSC academic group: Health

Ying joined the Sydney School of Public Health as a lecturer in International Public Health in January 2013. Before coming to Sydney, she was a National Health and Medical Research Council (NHMRC) Public Health Training Fellow at the University of Adelaide. Her research focuses on climate change and population health, particularly the adaptation to climate change among the elderly, both in Australia and in China. She is a Chief Investigator of national and international research projects on climate change and health. She is now collaborating with Chinese colleagues on a national key project (the 973 program) entitled “Climate change impacts on human health and adaptation mechanism research”.

Due to rapid increasing economic growth and rising energy demand, China has overtaken the USA as the largest single emitter of carbon dioxide since 2007, even though its per capita emissions are just one quarter of that of the US, and 60 percent of EU levels1. Nevertheless, the current development pattern in China brings a range of public health challenges. Many of the most important are related to environmental changes. Climate change is the clearest example. Observed data from the China Meteorological Administration show a 1.1°C increase in the average surface temperature in China between 1908 and 2007, higher than the 0.74 °C increase in the global average temperature2. Moreover, since the 1990s, China has experienced frequent extreme weather events, such as a 40-day episode heat-wave in Shanghai in 2003, the longest heat-wave recorded in the last 50 years. The severe drought in Yunan Province of southwest China in 2010 highlights the climate threat in China. More extreme weather events are likely to occur more frequently and intensively. It is projected that China will need 10 trillion yuan (approximately $1.6 trillion) by 2020 to mitigate climate change3.

Another fact of the 21st century is population ageing. The world population is rapidly ageing. Globally, the number of people aged 80 years and over will almost quadruple to 395 million by 20504. The majority of older people live in low- or middle-income countries with a projected 80% increase by 2050. Due to improved healthcare, as well as the one-child policy, the population in China as a whole is ageing faster than that in developed countries. The percentage of people aged 65 years and over in China has risen from 68 million in 1990 to 110 million in 2010, with a projected a quarter of the population aged over 60 (over 330 million) by 20505.

quote Both climate change and population ageing will have a profound impact on the Chinese environment, society and culture, which will bring significant challenges to the already overloaded public health system in China.

Double health burden from population ageing and climate change

Both climate change and population ageing will have a profound impact on the Chinese environment, society and culture, which will bring significant challenges to the already overloaded public health system in China. Being called the ‘biggest global health threat in the 21st century’, the health impacts of climate change and extremes have been evident globally6. Climate change would also exacerbate inequalities between and within countries. The most vulnerable are in developing countries. Climate change will have the greatest effect on health in societies that are already vulnerable due to a lack of resources, little technology and poor infrastructure. Research suggests that changes in climatic conditions have had and will lead to more cases of infectious diseases, injuries and non-communicable diseases (NCDs) in various regions of China7. The pubic health implications of population ageing mainly include changes in disease patterns, increased demand for healthcare for the elderly, and soaring health costs. According to the latest Global Burden of Disease Study 2010, the top three causes for premature deaths in China are stroke, ischemic heart disease and chronic obstructive pulmonary disease, together accounting for 30.4% of the total premature mortality8. The increasing number of older people with NCDs will lead to a greater need for long-term healthcare for the elderly. It is also noted that the elderly are amongst the most vulnerable to climate change and extreme weather events. For example, it is the elderly who are the most affected during heat-waves, with the highest proportion of deaths always occurring amongst those who are older. The 2003 heat-wave in Shanghai caused a 13% increase in total deaths and 19% in cardiovascular mortality9. Contributing factors to heat intolerance in the aged include an age-related decline in both general health and the physiological capacity to effectively regulate temperature. Multiple co-existing conditions, particularly cardiovascular diseases, are common in the elderly, thus resulting in is concomitant poly-pharmacy being required to treat these ailments. In addition, living conditions, socio-economic status and available support from communities and family can all affect the elderly in adapting to climate change and extreme weather conditions.

Help the elderly better adapt to climate change

China has committed to take action on climate change mitigation and adaptation by addressing the challenges and opportunities from the future environmental and demographic scenarios. China issued its first National Environment and Health Action Plan (2007-2015) in 2007, aiming to develop an efficient system for environmental health by 2015. The plan addresses some of the important issues regarding environment and health, such as the need to develop relevant laws and regulations, to establish nationwide surveillance networks and early warning systems and to share information among different government agencies and stakeholders. Unfortunately, even the most optimistic mitigation measures cannot reverse the accelerate increase in climate change and environment deterioration. Communities and individuals need to adapt.

quote The question is how we can achieve healthy ageing in a changing climate.

The question is how we can achieve healthy ageing in a changing climate. Strategies to prevent and reduce health burdens from climate change among the elderly, such as strengthening primary and secondary prevention of NCDs and providing more long-term health care, should be taken by the government at all levels, for all sectors. In addition, it is essential to understand older people’s perceptions, and attitudes towards climate change and extremes to assist in the development of intervention programs. Thanks to the support from the Endeavour Australian Award and the Australia-China Science and Research Fund, with colleagues at Shandong University, I conducted a questionnaire survey last year in Jinan, China, with 1200 participants of elderly living in the city and rural areas. Our study reveals that the Chinese elderly living in the rural areas are more worried about climate change but live with fewer resources to cope with the health impact of heat-waves. It suggests that the differences in choosing adaptive behaviors between urban and rural areas, as well as the socio-economic determinates, should be considered in developing adaptive strategies and targeted intervention programs for elderly Chinese. (The manuscript from this study is under preparation.)

There is a need to call for more collective efforts between China and other countries to deal with the consequences of climate change and population ageing, which are global issues faced by many developed and developing countries. In the White Paper on climate change, the Chinese government committed to “continuously increasing the financial support to climate change related scientific and technological work2.” For example, 30 million yuan (approximately AUD$4.6 million) has been allocated by the National Nature Science Foundation of China to conduct the first National Key Project to systematically assess the climate change impacts on human health. International collaborations are contributing to the successful completion of this project by 2015, and will assist in policy-making and capacity building to help the ageing population better adapt to climate change in the future.

1 United Nations Statistics Division (2009) Carbon dioxide emissions (CO2), thousand metric tons of CO2 (CDIAC). United Nation. Accessed May 2010. Available at
2 White Paper on China’s Policies and Actions for Addressing Climate Change. Information Office of the State Council of the People’s Republic of China. Beijing, 2008.
3 The Second National Assessment Report on Climate Change. Beijing, 2011.
4 World Health Day 2012 - Ageing and Health. WHO. 2012.
5 United Nations, Department of Economic and Social Affairs, Population Division, 2010. J Woo, T Kwok, KH Sze and HJ Yuan. Ageing in China: health and social consequences and responses. Int. J. Epidemiol. (2002) 31 (4): 772-775.
6 A Costello, et al. 'Managing the health effects of climate change’. The Lancet, vol. 373 (9676), pp. 1693-1733.
7 Zhang Y, Bi P, Jiang B. (2011) Climate Variability and Population Health in China: Updated Knowledge, Challenges and Opportunities. In: Climate Change - Socioeconomic Effects. Ed. Houshan Kheradmand: InTech Open Access Publisher. ISBN: 9789533074191. Available at :
8 The Global Burden of Disease Study 2010. China profile. Available at
9 Huang et al. The impact of the 2003 heat wave on mortality in Shanghai, China. Science of The Total Environment. (2010) 408 (11):2418-20.