Climate change is the greatest health threat of the 21st century, according to a report from a commission assembled by University College London’s Institute for Global Health and the Lancet. And two local health experts say there’s an urgent need to understand how global warming will affect our aging population.

“It’s absolutely guaranteed that the climate will be warmer 20, 30, 50 years from now than it is now,” says Heather Stewart, research associate at SFU’s Gerontology Research Centre and the UBC Brain Research Centre, in a phone interview along with GRC director Andrew Sixsmith. “But nobody is really talking very much about the impact on older people”¦.We need to start planning realistically.”

Sixsmith adds: “Population aging and climate change might seem to be separate topics, but when you start looking at issues of sustainability, they’re very much related. Both climate change—in particular, greenhouse gases—and the growing number of older people are byproducts of technological progress of the last 100, 200 years”¦.How are we going to live in the world long-term with those implications?”

Around the world, the number of people older than 60 is growing faster than any other age group. The World Health Organization, meanwhile, has concluded that changes in weather patterns are disrupting the balance of natural systems that supply the necessities of life: air, water, and food. When those basics are threatened, the elderly are among the hardest hit.

To get a firm grip on how—not if—the changing climate will affect the health of seniors, the upcoming 20th annual John K. Friesen Conference will focus on the impending challenges. Growing Old in a Changing Climate: Exploring the Interface Between Population Aging and Global Warming takes place May 25 and 26 at SFU’s downtown Segal Graduate School of Business. The conference series is named after the late educator and humanitarian who was a major contributor to SFU’s Gerontology Research Centre.

Sixsmith, the conference director, and Stewart, its program chair, note that the goals are to raise awareness of the connection between aging and climate change and to identify where research, resources, and action are most needed.

Speakers include Bettina Menne, medical officer of global change and health at the World Health Organization’s regional office for Europe; Sir Andrew Haines, professor of public health and primary care at the London School of Hygiene and Tropical Medicine; Kathy Sykes, senior adviser with the U.S. Environmental Protection Agency’s aging initiative; and Gloria Gutman, research associate at the SFU Gerontology Research Centre.

Environmental epidemiologist Carlos Corvalán, senior adviser on risk assessment and global environmental change with the Pan American Health Organization and the WHO, will give a free public lecture on climate change and human health on the night of May 25.

The toll that global warming can take on vulnerable populations was seen during the heat wave that hit Europe in 2003. More than 30,000 people died, largely because of cardiovascular and respiratory conditions, and, with temperatures reaching 41.5 ° C, the elderly were most affected.

But the health effects of climate change can be caused by many things besides extreme heat.

According to the abovementioned report issued by the Lancet–Institute for Global Health commission, rising temperatures will affect the spread and transmission rates of vector-borne and rodent-borne diseases, for example. Temperature affects the rate of pathogen maturation and the density of insects in a particular area. Vector reproduction, the parasite-development cycle, and bite frequency tend to rise with temperature. So conditions like malaria, tick-borne encephalitis, and dengue fever will become increasingly widespread.

Furthermore, mosquitoes carrying malaria will likely start to appear in places previously free of the disease, areas that are increasingly warm. As many as 320 million more people will be affected by malaria by 2080 because of new transmission zones. About six billion people will be at risk of contracting dengue fever by 2080 as a result of climate change, compared with 3.5 billion people if the climate were to stay the same.

There’s more. As ocean temperatures go up, cholera outbreaks might rise too. Floods promote outbreaks of cryptosporidiosis. Rising sea levels and the flooding of coastal areas can lead to the contamination of fresh water and agricultural lands, plus the loss of nursery areas for fishing.

Drought, changing rates of plant and livestock diseases and pest infestations, and diminished crop yields and forest productivity will all affect food production and security.

To make matters worse, health problems can be exacerbated by the breakdown of sanitation, drainage, and water-supply systems. Then there is the potential for escalating rates of mental-health conditions, such as depression and anxiety, following natural disasters.

The commission report makes it clear that no nation, no matter how prosperous, will be immune to the health effects of climate change.

But urgent, collective action can help mitigate the potential for disastrous consequences. “We call for a public health movement that frames the threat of climate change for humankind as a health issue,” the commission report states. “Apart from a dedicated few, health professionals have come late to the climate change debate.”

Vancouver’s Stewart and Sixsmith are as hopeful as they are confident that the conference, the first of its kind, will attract everyone from health professionals, government representatives, and environmental experts to researchers, community planners, and scientists.

“We want to identify some gaps and address the unknowns,” Stewart says. “What are the key areas we need to focus on? We need to understand these issues in more depth.”