Climate change is already seriously harming both public health and labor productivity, warns a major new study published Monday in the prestigious Lancet medical journal.

“The delayed response to climate change … has jeopardised human life and livelihoods,” concludes the comprehensive Lancet Countdown, a joint project of two dozen universities and intergovernmental organizations around the world. Warming since 2000 alone has led to “an estimated reduction of 5·3% in outdoor manual labour productivity worldwide.”

The authors add that “another slow response will result in an irreversible and unacceptable cost to human health.”

The report documents how global warming is aiding the spread of disease-carrying insects, worsening allergies, and dramatically boosting exposure to ever-worsening heat-waves. Many of the findings are shocking: “125 million more vulnerable people over the age of 65 years were exposed to heatwaves in 2016 than in 2000.”

This is a dangerous increase in the number of elderly exposed to extreme heat, which, the authors note “causes heat stress and heat stroke, exacerbations of pre-existing heart failure, and kidney disease.”


Unfortunately, the trend toward ever-stronger heat waves and greater exposure to vulnerable populations is certain to continue. Indeed, an August study by the European Union’s science and research lab, found that “if global temperatures rise by 4°C [7°F], a new super heat wave of 55°C [131°F] can hit regularly many parts of the world, including Europe” and the United States.

Tragically, 7°F warming is what top U.S. scientists say we should expect if the Trump administration’s sweeping reversal of climate policies continue to prevail, and both domestic and global climate action are undermined.

Although the focus of this report is public health, the Lancet also examines the economic impacts of global warming. If you live and work in rural areas — like many Trump voters, for instance — the impact will be particularly harsh. Indeed, for many in this country and around the globe it already has.

The study finds that “global labour capacity of rural labourers, such as farmers, has fallen by 5.3 percent from 2000 to 2016 due to rising temperatures and the inability to work when it’s too hot.” Labor capacity is “the number of hours spent actively working as a percentage of the total hours available for work.” The physical impact of heat on humans performing manual labor outdoors simply reduces their capacity to work, and hence their productivity (output per worker).

Change in labor capacity (and thus productivity) globally and for rural regions specifically, compared to 1986–2008 average. CREDIT: The Lancet

Rising temperatures “pose profound threats to occupational health and labour productivity, particularly for people undertaking manual, outdoor labour in hot areas.” The Lancet notes that labor capacity saw “a dramatic decrease of more than 2 percent between 2015 and 2016.”


While many of the hardest hit places are in the developing world, parts of the Southern United States are already seeing a significant impact of rising temperatures on outdoor labor capacity, as this chart shows:

Change in labor capacity compared to 1986–2008 average. CREDIT: Lancet

Again, we know that much worse is yet to come. A 2013 NOAA study concluded that “heat-stress related labor capacity losses will double globally by 2050 with a warming climate.”

In fact, by the 2080s, much of the Southern U.S. will see temperatures above 90°F for five months of the year or more, according to the congressionally-mandated 2014 U.S. National Climate Assessment. And that’s a startling change from just the recent past.

Large parts of the South will be all but uninhabitable outdoors for large parts of the year.

NOAA’s 2013 study warned that in the case of 7°F or higher warming, we face as much as a 50 percent drop in labor capacity in peak months by century’s end — versus a more manageable 20 percent drop if we sharply reverse emissions trends immediately.

The productivity loss from warming could exceed the “combined cost of all other projected economic losses” from climate change, explained one expert — and yet it has “never been included in economic models of future warming.”


The new Lancet report — like many other analyses — makes clear that it’s not too late to avoid the worst health and labor impacts from global warming. But a quarter-century of dawdling has left us no more time to delay.