A record-breaking heat wave in India exposing hundreds of millions to dangerous temperatures is damaging the country's wheat harvest, which experts say could hit countries seeking to make up imports of the food staple from conflict-riven Ukraine.
With some states in India's breadbasket northern and central regions seeing forecasts with highs of 120 Fahrenheit this week, observers fear a range of lasting impacts, both local and international, from the hot spell.
Indian Prime Minister Narendra Modi told U.S. President Joe Biden earlier this month that India could step in to ease the shortfall created by Russia's invasion of Ukraine. The two countries account for nearly a third of all global wheat exports, and the United Nations Food and Agriculture Organization has warned that the conflict could leave an additional 8 million to 13 million people undernourished by next year.
India's wheat exports hit 8.7 million tons in the fiscal year ending in March, with the government predicting record production levels — some 122 million tons — in 2022.
But the country has just endured its hottest March since records began, according to the India Meteorological Department, and the heat wave is dragging well into harvest time.
The heat wave is hitting India's main wheat-growing regions particularly hard, with temperatures this week set to hit 112 F in Lucknow, Uttar Pradesh; 120 F in Chandigarh, Punjab; and 109 F in Bhopal, Madhya Pradesh.
Devendra Singh Chauhan, a farmer from Uttar Pradesh's Etawah district, told NBC News that his wheat crop was down 60 percent compared to normal harvests.
"In March, when the ideal temperature should rise gradually, we saw it jump suddenly from 32 C to 40 C [90 F to 104 F]," he said in a text message. "If such unreasonable weather patterns continue year after year, farmers will suffer badly."
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Harjeet Singh, senior adviser to Climate Action Network International, said the heat wave would have a "horrific" short- and long-term impact on people in India and further afield.
"[Wheat] prices will be driven up, and if you look at what is happening in Ukraine, with many countries relying on wheat from India to compensate, the impact will be felt well beyond India," Singh said.
Harish Damodaran, senior fellow at the Delhi-based Centre for Policy Research, said regions that planted earlier tended to escape the worst impacts on their harvests. In other regions, however, the hot temperatures hit during the wheat's crucial "grain filling" stage, which is critical for producing high yields.
"Temperatures just shot up," he said. "It was like an electric shock, and so we are talking of yields more or less everywhere coming down 15 to 20 percent."
"I don't know if India will be able to meet export demand because it is going to create issues in domestic supply, as wheat prices go up," Damodaran added. "India cannot replace Russia and Ukraine with its wheat exports, mainly because of this heat shock."
Monika Tothova, an economist with the U.N.'s Food and Agriculture Organization, was more measured. She said although the heat wave would likely cause some "localized crop losses … a significant impact on the world market is not implicit."
She said India still had good wheat stockpiles and may be able "at least in part" to cover from some sourcing shortfalls due to the situation in Ukraine.
Scientists also voiced concern about the human cost of India's extreme hot spell.
The U.N.'s Intergovernmental Panel on Climate Change in a bombshell February report said global warming meant hundreds of millions were already or would soon be at risk of exposure to extreme heat, depending on carbon emissions.
By 2100, it said half to three-quarters of humanity would be exposed "to periods of life-threatening climatic conditions arising from coupled impacts of extreme heat and humidity."
Chandni Singh, an environmental social scientist at the Indian Institute for Human Settlements, said while the heat wave may not produce headline-grabbing death tolls, the damage from this and future hot spells would be nonetheless significant.
"People in informal settlements or those working in labor-intensive outdoor jobs are most affected, with few options or resources to cool their homes," she said.
The U.N. projected near-term increased temperature and humidity across the Indian subcontinent due to climate change. This means hundreds of millions could face higher so-called wet-bulb temperatures, where air cannot be cooled by water evaporating and perspiration alone is unable to cool a human body.
A wet-bulb temperature of 95 F is unsurvivable for more than six hours, even for healthy adults resting in the shade.
"I am most concerned about the impacts this will have on informal livelihoods in cities that often occur in cramped, poorly ventilated spaces, often from peoples' homes," Singh said.
Roxy Mathew Koll, a climate scientist at the Indian Institute of Tropical Meteorology and a lead IPCC author, said while more research was needed to link the current heat wave directly to climate change, "the root cause for increasing heat waves in the Indo-Pakistan region is global warming due to human-made carbon emissions."
He said some Indian cities had learned lessons from previous deadly hot snaps, such as limiting office hours and implementing early warning systems.
But these were short-term measures that failed to address the increasingly frequent and extreme temperatures that lie in India's near future, Koll said.
"After seeing my son coming from school in a heat-struck condition, we talked to the school principal, showing the data and heat wave forecasts. They immediately reduced the school hours," he said.
"However, this is just for one school," Koll said. "We need such policies to work out at a government and state level."