• India will lose 101 billion work-hours a year to the effects of global warming, according to a new study.
• There is more scientific evidence to show how extreme weather, including rainfall, impacts economies worldwide.
• Another study found economic growth decreases when the number of wet days and the number of days with extreme rainfall increase.

Kochi: As the world becomes warmer, India will lose more than 101 billion hours of labour every year, the highest of any country in the world, according to a new study.

Working in hotter climes is inefficient and affects public health. An effective adaptation strategy is to move work-hours from the middle of the day to early in the day – but as the planet warms further, even this strategy will become less effective, according to the study.

Although there are some efforts in India to attempt to ameliorate the loss of productivity due to climate change, climate economists believe we still have a long way to go.

Working for many hours under a scorching Sun can become quickly tiring. The human body usually cools itself by sweating. But on humid days, sweat evaporates less easily because the air already holds a lot of moisture. As a result, the body doesn’t cool, sweats more, doesn’t cool as much, sweats even more, and so forth. So working outdoors in such conditions means more breaks, slower work and, most of all, adverse impact on workers’ health.

With global warming, such hot, humid days will be becoming more common in India. According to the latest report of the Intergovernmental Panel on Climate Change, India will experience more heat waves – spells of excessively hot weather often characterised by high humidity. Another report suggested heatwaves in India are also likely to last longer, by up to 25x, in the next four decades if carbon emissions remain high.

A team of scientists from the universities of Duke, Stanford, North Carolina and Washington used meteorological data from around the world and climate models to estimate humid heat exposure in various countries. They also compiled data on current labour losses to project labour losses under scenarios of additional warming.

The cost of climate change

In the last two decades alone, they found that 228 billion hours on average of heavy labour have been lost every year due to heat exposure worldwide. The agriculture sector suffered the most, losing around 220 billion hours in 2016 and 217 billion in 2019.

Labour losses also appeared to spike in El Niño years, when the tropical Pacific Ocean warms more than usual in a recurring pattern.

Global economic losses associated with this ‘missing’ productivity could amount to $1.6 trillion every year if Earth’s surface warms to 2º C more than it is today.

“Luckily, about 30% of this lost labour [worldwide] can still be recovered by moving it to the early morning,” Luke Parsons, a postdoctoral associate at Duke University, North Carolina, and a member of the study, said in a press release. “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 labour.”

Of the 163 countries the researchers studied, India emerged as the worst-hit, losing in excess of 101 billion hours of labour every year. The country also seems set to retain its pole position in the coming years, together with China, Pakistan and Indonesia.

While we’re familiar with the challenges of adapting to higher temperatures, this study is an “important accounting” of work-hours that will be lost under future warming scenarios, according to Ashwin Seshadri, an assistant professor at the Indian Institute of Science’s Divecha Centre for Climate Change and Centre for Atmospheric and Oceanic Sciences. He was not involved with the study.

But apart from shifting work hours, there are several other measures, like reducing the intensity of work and allowance for longer breaks, that the study doesn’t consider in its analyses.

Indeed, the types of adaptation that are chosen will play a role in dealing with warmer temperatures, Seshadri said – but these will be more out of requirement than choice.

“I think one of the lessons of this work is that any such adaptation is likely to be less than perfect, because warming impacts will be felt even during the cool hours of the day,” he wrote in an email to The Wire Science.

That India loses so many labour-hours per year is interesting because it reflects India’s economic structure, Amir Bazaz, senior lead – practice, at the Indian Institute for Human Settlements, Bengaluru, said.

This is because labour-based activities dominate the agriculture sector and are a major component of the urban economy. “So we need to be mindful [enough to] ensure both productivity and livelihoods are not lost when temperatures increase,” Bazaz said.

Bazaz and his co-authors wrote in a 2021 review that the economic costs of climate change won’t be borne uniformly within the country either. Income and wealth levels, gender relations and caste dynamics will likely intersect with climate change to perpetuate and exacerbate inequalities, they wrote.

And addressing these issues – which also affect the productivity and economy of the country – will be crucial, Bazaz added.

Rainfall and the economy

Similarly, excessive rains due to climate change have impacted and will impact the economy as well. Previous studies, such as this one in 2020, have shown that while extremes have a negative impact, higher rainfall can benefit economies – especially those in dry areas that depend on agriculture.

However, these benefits drop when total rainfall across the year increases, scientists at Germany’s Potsdam Institute for Climate Impact Research have found. They studied both rainfall and its extremes between 1979 and 2019, in more than 1,500 regions around the world. They also found that economic growth decreases when the number of wet days and the number of days with extreme rainfall increase.

Economies, they added, have adapted to present levels of rainfall so much that extreme deviations cause significant losses.

These results are consistent with regard to the Indian monsoon, Seshadri said. “The asymmetry between the adverse impact of deficit rainfall on yields (as well as agriculture GDP) and the limited benefit of excess rainfall is now well known, thanks to some important analyses of the past two decades.”

But changes in temperature and rainfall can often work together to influence economic growth – and it is often difficult to tease the impact of the two forces apart. Since the authors have accounted for regional and yearly fixed effects on economic growth, in addition to effects of temperature, it’s quite possible that what the study finds is really the effect of rainfall, Seshadri said.

But estimates of impact on economies do come with caveats.

“Even if one considers economic output, estimating the impact of weather variables on GDP is fraught with the complexity of economies and impacts of numerous (known and unknown) factors on the chosen measures,” according to Seshadri.

Another “very important study”, in the words of K.S. Kavikumar, an associate professor at the Madras School of Economics, Chennai, was based on the Indian manufacturing sector and used firm-level data to show that in the absence of climate control, worker productivity declines and absenteeism increases on hot days.

“They estimate a significant fall of about 2% in annual plant output in India per degree celsius,” he wrote in an email to The Wire Science.

We don’t have similar estimates of the effects of heat stress on labour productivity and morbidity in other labour intensive sectors, like agriculture, in India. In fact, the likely losses in labour productivity in agriculture could be significant – due to high exposure as well as costly and/or infeasible climate control measures in agriculture, Kavikumar added.

For example it is relatively easy to install cooling devices in factories to protect workers from temperature-induced heat stress, but such measures are almost impossible to implement in agricultural fields and as a result the scope for mitigating the losses is minimal.

There are some ongoing efforts to deal with labour losses due to extreme weather; many states have action plans that try to plan ahead, Bazaz said. For example, Ahmedabad was the first Asian city to have its own ‘heat action plan’, after 1,300 workers lost their lives to heat stress in May 2010. The plan also consists of an early warning system and measures to raise awareness about heat preparedness.

India urgently needs to pay more attention to developing such plans that respond to extreme weather events, and implement them through efficient, effective and agile institutional and governance structures and processes, according to Bazaz.

“But we have competing priorities given the financial resources available,” he continued. According to him, finding innovative ways to give more money to local governments and to crowd in financial flows for local climate action in order to address local priorities would be crucial too.