Older People and Climate Change: Vulnerability and Health Effects

Adaptation, by the community and the individual, can make a difference. Climate change has the potential to affect the environment in a number of ways that place increased stress on everyone, but disproportionately on the most vulnerable populations, including the young, the old, those with chronic illness, and the poor. Older people are among the most at risk because of decreased mobility resulting from age, changes in physiology, and more restricted access to resources, all of which may limit adaptive capacity. The challenges older people will face adapting to climate change have potentially far-reaching implications for the health of individuals and the population as a whole. A number of societal strategies to cope will be required. Habitability, health, and environmental justice will be challenged as the adverse effects of climate change interact with factors that are characteristic of older people. Overview of Climate Change The Intergovernmental Panel on Climate Change (IPCC) (2007a), a scientific body formed to evaluate the risks of climate change, has prepared their fourth assessment on the scientific, technical, and socioeconomic information relevant for the understanding of the risk of human-induced climate change. Their findings indicate that use of fossil fuel, agricultural practices, and changes in land use have been the dominant cause of the increase in greenhouse gases emitted to the atmosphere over the past 250 years. Global mean surface temperatures have continued to rise as these associated emissions have increased. Eleven of the last twelve years rank among the twelve warmest years on record since 1850. Since the 1970s, droughts have become more common, especially in the tropics and subtropics. Furthermore, since 1961, global average sea level has risen at a mean rate of 1.8 millimeters per year and even higher since 1993, at 3.1 millimeters per year, with contributions from thermal expansion, melting glaciers and ice caps, and the degeneration of the polar ice sheets. These findings indicate that unabated climate change will have serious impacts on the environment and on food production, political stability, and human health. Heightened Vulnerability For older adults, the changing climate brings heightened vulnerability to environmental risks, which include extreme weather events, exacerbated vectorborne diseases, compromised agriculture, reduced availability of fresh water, and decreased habitability of human population centers. Older people are more vulnerable to the effects of temperature extremes and have a significantly higher mortality risk in extreme weather events. The older population is also at greater risk because of increased susceptibility to disease and to the effects of stresses on the food and water supply, and reduced ability to mobilize quickly. The health effects of climate change on older people can be classified into two categories: (1) those due to the greater exposure of older people to the threat ("the dose" in public health terminology) and (2) those that are a combination of exposure plus greater reactivity as a characteristic of aging (increased physiological susceptibility) or social factors that vary across individuals (social vulnerability). Overall, the research literature suggests that greater physiological susceptibility and social vulnerability may best account for many of the negative health effects of climate change on older people. The effects of climate change are variable, depending on pre-exposure health status, psychological well-being, and social characteristics (Geller and Zenick, 2005). Indeed, turning age 65 does not in itself make a person more vulnerable to the negative effects of climate change. Rather, it is the individual physiological and social factors associated with aging that may bring greater negative impact. For example, the oldest old (age 85 and over) are more likely to suffer negative health effects from climate change (Haq, Whitelegg, and Kohler, 2008) because of physical decline or frailty (McGeehin and Mirabelli, 2001). …