The Climate Crisis Is Also a Global Health Crisis

 The Climate Crisis Is Also a Global Health Crisis

Stewart M. Patrick Monday, Nov. 1, 2021

Climate change is bad for your health. That is the unequivocal finding of The Lancet’s annual “Countdown” report, which was published last week by a team of nearly 100 scientists from 43 institutions around the world. Global warming, the authors write, is not just an environmental disaster, but is also exposing humans to searing heat and extreme weather events; increasing the transmission of infectious diseases; exacerbating food, water and financial insecurity; endangering sustainable development; and worsening global inequality. And, they conclude, the data in this year’s report should represent a “code red for a healthy future.”

For the past two years, the coronavirus pandemic has naturally been the overwhelming focus of global public health discussions, having infected nearly 250 million people, while killing almost 5 million and upending the world economy. The health effects of climate change have been more subtle, yet relentless. The pandemic will pass, sooner or later, but the health challenges created by global warming will last decades, even centuries. 

So far, world leaders have largely failed to address the health challenges brought on by climate change. In fact, in a joint statement released in September, more than 200 medical journals identified this political negligence as the “greatest threat to global public health.” To arrest and ultimately reverse these trends, world leaders should take advantage of the U.N. Climate Change Conference in Glasgow, which kicked off on Sunday, by agreeing to accelerate the decarbonization of the global economy and provide more funds to low-income countries for adaptations to global warming’s public health impacts. 

The negative impacts of climate change are both direct and indirect, but the most obvious is humanity’s heightened exposure to extreme heat, which can be fatal, particularly for those over the age of 65 and children under 1. Globally, deaths among older people officially attributed to heat reached a record high of 345,000 in 2019, according to The Lancet, a number that is undoubtedly an undercount. 

While wealthier countries have not been spared—as the extraordinary “heat dome” that baked the U.S.’s Pacific Northwest this summer attests—it is developing nations that bear the heaviest brunt, with agricultural workers suffering the most. At times, high heat simply makes it impossible to work. During 2020, India, Bangladesh and Pakistan lost more than 200 hours of labor per employed person due to high heat. That is equivalent to more than five 40-hour work weeks per worker. Heat, then, exacerbates poverty, which in turn leads to poorer health outcomes. And beyond its physical effects, high heat exacts a grievous mental health toll, encouraging suicidal ideation and other forms of psychological suffering.

Perhaps less obviously, global warming also subjects humans to extreme weather events, water and food insecurity, displacement and new disease threats. Since 2000, wildfire risk has risen sharply, exposing populations to immediate dangers as well as to the long-term debilitating effects of smoke inhalation. The incidence of lethal natural disasters like hurricanes has also surged since 2000, while droughts are increasing in “frequency, intensity, and duration,” according to The Lancet’s report. 

The pandemic will pass, sooner or later, but the health challenges created by global warming will last decades, even centuries.

Meanwhile, 19 percent of the Earth’s surface now experiences drought in any given month, a trend that has endangered reliable access to water and food. Globally, yields of staple crops like maize, soybeans, winter wheat and rice have all declined when compared to 1980-2010 levels. Rising ocean temperatures and ocean acidification also threaten the marine food sources upon which 3.3 billion people depend for nutrition and livelihoods, particularly in developing countries. All told, during 2019, some 2 billion people—more than a quarter of humanity—were food insecure, the Lancet found.

Cumulatively, these trends are likely to generate a surge in “climate migrants,” with negative health consequences for those uprooted from their homes. Among the most vulnerable are those currently living in coastal communities situated less than a meter above sea level, an estimated 146.6 million people. Another 400 million-plus who live less than 5 meters above sea levels today face “increased risks of flooding, more intense storms, and soil and water salinification,” The Lancet explained.

Finally, the report notes that climate change is increasing human vulnerability to certain infectious diseases, including water-borne pathogens and arboviruses spread by mosquitos, ticks and arthropods. Thanks to higher global temperatures, mobility and urbanization, the incidence of dengue fever, a viral disease spread by mosquitos, has doubled every decade since 1990. Global warming has also increased the geographic range of Plasmodium falciparum, the deadliest species of the parasite that causes malaria, including to highland areas that were once out of its reach. Meanwhile, higher temperatures and changes in the surface salinity of coastal waters have created more favorable conditions for the transmission of the bacteria responsible for cholera and other illnesses that spread through water. 

In response to these threats, The Lancet’s authors call on nations to invest in health-related climate adaptations; link their mitigation efforts to global health priorities; accelerate the transition to a post-carbon world economy; and expand public and private engagement to reduce the global health inequities exacerbated by climate change. While a number of countries have incorporated health considerations in their national adaptation strategies, only a tiny proportion of the actual funding has been directed to improving health systems—0.3 percent—or to broader health-related initiatives—5.6 percent. International donors have pledged to mobilize $100 billion in green financing annually, and to devote half of this to adaptation. Going forward, both donor and recipient nations must target a chunk of these resources to public health resilience. 

In parallel, countries must accelerate their efforts to mitigate climate change and make explicit mitigation’s connection to positive global health outcomes. Phasing out coal and transitioning to clean energy, for instance, promises to reduce mortality from ambient air pollution, which kills an estimated 3.3 million people a year. Likewise, shifting toward more sustainable agricultural production, including decreasing red meat consumption, will pay dietary as well as climate dividends. 

Achieving these health objectives will of course require a far higher level of climate ambition than political leaders have shown to date. National governments have paid lip service to “green recovery” strategies that will supposedly help them meet the Paris Agreement goal of limiting average warming to 1.5 degrees Celsius, a target that implies cutting emissions in half in just nine years and achieving carbon neutrality by 2050. These declarations ring hollow. According to the U.N. Environment Program’s latest Emissions Gap Report, released last week, global temperatures are set to rise 2.7 degrees above preindustrial levels by 2100, with catastrophic consequences for human well-being. At its current pace, the world will not fully decarbonize for 150 years.

As it seeks to emerge from the COVID-19 pandemic, the world confronts a fateful choice. It can lock the world economy into an emissions trajectory that The Lancet says “will damage the health of current and future generations.” Or it can pursue a green recovery that enhances the health of both the Earth and its inhabitants. As the World Health Organization’s climate and health coordinator, Diarmid Campbell-Lendrum, said in 2018, “If a person’s temperature chart looked like our planet’s, you’d intervene. You wouldn’t wait [until] the autopsy.”

Stewart Patrick is the James H. Binger senior fellow at the Council on Foreign Relations and author of “The Sovereignty Wars: Reconciling America with the World” (Brookings Press: 2018). His weekly WPR column appears every Monday.