Outdoor jobs such as agricultural or construction work could become impossible to perform safely on hot afternoons in many parts of the world, NASA-funded study warns
Rising heat and humidity caused by climate change is expected to significantly dampen labour productivity throughout the world, with costs to the global economy potentially reaching up to $1.6tr each year from lost working hours if global warming exceeds levels of around 3C, fresh scientific analysis suggests.
Funded by NASA, the peer-reviewed study published today warns that critical jobs such as agricultural and construction work could become almost impossible to perform safely during hot afternoon hours in the summer in many parts of the world as climate change worsens.
As heat and humidity levels rise throughout the day due to climate change, options for moving outdoor labour to cooler hours is expected to dramatically shrink, thereby leading to significant losses in productivity, according to the study, which was led by researchers from Duke University in the US.
The research projects future labour productivity losses from warming across every country worldwide under different climate scenarios ranging from just 1C up to 4C warming relative to present temperatures.
At present, it is estimated the world already loses around $280-311bn each year due to workers struggling in hot, humid conditions. But today’s study warns that, if average global temperatures rise by another 2C relative to the present – which would amount to over 3C of warming above pre-industrial levels – labour losses in the coolest half of the day could exceed current losses in the hottest half.
Moreover, developing economies where larger numbers of people work outdoors are set to be hit the hardest, with workers plying their trade in tropical and subtropical regions – particularly in Asia, the Middle East, Africa, and the Western Pacific – expected to bear the worst impacts, the study predicts.
India, China, Pakistan, and Indonesia, where larger proportions of the population work outdoors, are set to experience the biggest losses overall, according to the study, which has been published today in the journal Nature Communications. But it warns 14 smaller countries could experience higher per-capita losses, including Bangladesh, Thailand, Gambia, Senegal, Cambodia, United Arab Emirates, Bahrain, Qatar, Brunei Darussalam, Ghana, Togo, Benin, Sri Lanka, and Nauru.
“Sadly, many of the countries and people most impacted by current and future labour losses are not responsible for the bulk of greenhouse gas emissions,” explained Luke Parsons, a climate researcher at Duke University’s Nicholas School of the Environment, who led the study.
“Many workers in the tropics are already stopping work in the afternoon because it’s too hot,” he added. “Luckily, about 30 per cent of this lost labour can still be recovered by moving it to the early morning. But with each additional degree of global warming, workers’ ability to adapt this way will swiftly decrease as even the coolest hours of the day quickly become too hot for continuous outdoor labor.”
The scientists used a blend of observation-based meteorological data and climate model projections for temperatures and humidity to estimate humid heat exposure, current labour losses, and projected future labour losses under additional warming.
Yet despite the bleak projections in the study, Parsons stressed that by limiting average warming to around 2C above pre-industrial levels, as agreed under the Paris Agreement, it should still be possible to avoid the worst worker productivity losses by shifting heavy labour activities to the early morning hours when it is generally cooler.
“But if warming exceeds 1C [above current levels], that becomes much more difficult,” Parsons said. “It’s a sliding curve, it gets exponentially worse as the temperature rises.”
The study comes on the same day as two separate reports on worrying new climate records, with the World Meteorological Organisation confirming a 38C temperature reading in Siberia in summer 2020 represented a new high for the Arctic Circle, while a team of scientists warned a meeting of the American Geophysical Union that new fissures detected at the foot of Antarctica’s giant Thwaites Glacier suggest it could break apart within the next five years. The massive ice sheet, which is the size of Florida, is already estimated to be producing meltwater that is responsible for around four per cent of global sea level rise and experts fear the fresh cracks point to how the melting of the entire West Antarctic Ice Sheet could accelerate rapidly over the coming decades with significant implications for global sea levels over the course of the century.
