Older people face increasing health risks from extreme heat as climate change intensifies, the United Nations Environment Programme (Unep) has warned.
(Envato Elements)
Older people face increasing health risks from extreme heat as climate change intensifies, the United Nations Environment Programme (Unep) has warned.
In the latest edition of its Frontiers Report, released this week, it said adults aged 65 and above are becoming an increasingly dominant part of societies worldwide, especially in the cities of low and middle-income countries.
The report highlights other effects of climate change, including the melting of glaciers that reawaken ancient pathogens and floods that risk releasing dangerous chemicals, as well as potential solutions to these emerging environmental issues.
Older people are highly vulnerable to extreme weather events. Since the 1990s, there is an estimated 85% rise in annual heat-related deaths of older people. Poor air quality arising from extreme weather events also results in subsequent health issues. Similarly, floods affect low-lying coastal cities, which are home to many older persons.
The global population aged 65 and older is projected to increase from 10% in 2024 to 16% by 2050, primarily in low and middle-income countries, the report notes. Concurrently, climate change is exacerbating risks such as heatwaves, air pollution and floods, which disproportionately threaten older human beings.
The world is also becoming increasingly urbanised, with about 57% of its population now living in cities. By 2050, this figure is expected to rise to 68%.
“A rising number of cities will therefore soon face the new reality of increasingly ageing urban dwellers. Maintaining good health and vitality is crucial at any age and minimising risk factors for diseases become even more critical as we age,” the report said.
“In addition to the genetic, physiological, behavioural and social influences, environmental conditions play a crucial role, especially in cities that bring together a high concentration of a variety of environmental health risks.”
The risks of respiratory, cardiovascular and metabolic diseases, and the increased risk of mortality, become particularly acute for frail people with reduced mobility and chronic health issues.
Air pollution and chemical contamination increase the risk of cardiovascular and respiratory diseases, neurodegenerative diseases, dementia, depression and anxiety. Poverty, crowded cities and social isolation also raise the vulnerability of older people.
The report recommends transforming cities into age-friendly, pollution-free, resilient, accessible spaces with expansive vegetation through better urban planning.
Investing in weather stations to monitor extreme heat is critical to protect lives while community-based disaster risk management and access to information are key approaches to help aging people adapt successfully to climate change, it said.
The report follows the United Nations Human Rights Council resolution 58/13 to develop an “international legally binding instrument on the human rights of older persons”.
Zombie microbes
It warns of the “awakening” of ancient microbes in the cryosphere, which makes up half of the Earth’s land surface.
Should global temperatures rise more than 2˚C above pre-industrial levels, this would significantly reduce the cryosphere in mass, which includes glaciers, seasonal snow, ice sheets and shelves, sea ice, seasonally frozen ground, and permafrost. “In a best-case scenario, it would take centuries for cryosphere conditions to return.”
The cryosphere is surprisingly rich in ancient life, including fungi, bacteria, and viruses, of which some are pathogens. Much of this life is currently dormant. Warming could reactivate and remobilise modern and ancient microorganisms in cryospheric environments.
“Some might thrive, modifying existing microbial communities, while some might not survive resulting in a loss of microbial diversity.This can enhance the powers of existing pathogens through natural gene transfers, resulting in heightened risk of antimicrobial resistance,” said the report.
Cryospheric regions are home to 670 million people. This population could rise to 844 million by 2050, spanning the Alps, the Andes, Greenland, Hindu Kush Himalaya, Siberia, and the Tibetan Plateau as well as billions more who live in areas with water originating from those frozen areas.
To slow down the decline of the cryosphere, the report recommends cutting greenhouse gas emissions — including black carbon emissions from diesel engines — open-field agricultural burning, and wildfires and limiting tourism in fragile frozen regions. Scientific research must also accelerate into the diversity of cryospheric microorganisms that will not survive the cryosphere’s decline.
Banned chemicals re-emerge
Global climate change is contributing to longer, more severe, and more frequent floods. A flood can carry significant volumes of sediment and debris, the report said.
Sediments and debris often include common inorganic toxic pollutants, for example arsenic, cadmium, chromium, lead, manganese, mercury or persistent organic pollutants (for example pesticides), sometimes preserved in the environment over centuries.
When floods occur, these can re-enter cities or the food system. The persistent nature of these chemicals means even banned and phased-out chemicals can be remobilised.
In recent years, extreme rainfall and subsequent flooding have demonstrated their ability to remobilise legacy pollutants accumulated in the environment.
Extensive petroleum operations and incidences of oil spills in the Niger Delta of Nigeria over decades has led to severe contamination with ecological and human health consequences, the report said.
A catastrophic flood event in the Niger Delta in 2012 mobilised sediments contaminated with carcinogenic polycyclic aromatic hydrocarbons and deposited them over extensive portions of the floodplain.”
After the worst flooding in more than 100 years along the Elbe River in the Czech Republic and Germany in 2002, hexachlorocyclohexane concentrations in fish downstream of former production sites of the pesticide, lindane, increased more than 20-fold.
The same flood also mobilised legacy radionuclides and heavy metal pollutants from former uranium-mining waste dumps and tailing ponds in the Elbe region.
The Pakistan flood of 2010 inundated a fifth of the country’s total land area. It, together with a series of smaller flash floods, swept away a significant but unknown portion of 2 835 metric tonnes of obsolete pesticides and other persistent organic pollutants kept in storage facilities for proper disposal.
“The release of these obsolete chemicals into the environment will likely cause further contamination in soils, water, and sediments, and the damage needs to be monitored and assessed,” the report said.
Effective measures to reduce this imminent risk include traditional control measures like polders, dikes and retention basins, improved drainage systems, nature-based solutions like the sponge-city approach, regular monitoring of pollutants in diverse locations and products, and studying and tackling the economic impacts of this kind of pollution.
The risk of ageing dams
Another emerging threat the report addresses is the risk of ageing dams. It notes that alongside many benefits, dams can harm indigenous and fishing-dependent communities, as well as degrade ecosystems.
There are about 62 000 large dams and millions of smaller barriers that exist worldwide, with expected effects on 90% of the world’s river volume by 2030. Large ageing dams are increasingly being removed in Europe and North America, once they become unsafe, obsolete, or economically unviable.
Greater natural river connectivity means healthier ecosystems and greater biodiversity, renewing species’ access to tens or even hundreds of kilometres of upstream habitats.
The report noted, however, that where urbanisation, industrial agriculture or deforestation are common, dam removal alone may not significantly improve a river’s health. Large dam removals have the largest impact, though removing multiple small barriers may result in similar effects.
Adhering to the UN’s principles for ecosystem-restoration initiatives when considering the removal of river barriers is critical, the report said.