As Delhi’s mercury soared past 45 degrees Celsius on Tuesday, the city’s most vulnerable residents faced an impossible choice: risk heatstroke by working under the unrelenting sun, or lose a day’s wage and go hungry. This is the brutal arithmetic of a warming world, where climate change amplifies existing inequalities. The heatwave has already claimed dozens of lives, with hospitals reporting a surge in heat-related illnesses.
For millions living in informal settlements without reliable access to electricity or running water, the heat is not an inconvenience but a mortal threat. Women walk miles to fetch water, children suffer from dehydration, and labourers continue construction work because stopping means no pay. “We know it’s dangerous, but what choice do we have?” said Sunita Devi, a 34-year-old construction worker. “If I don’t work today, my children don’t eat.”
This reality is precisely what climate scientists have warned about for decades: extreme heat events are becoming more frequent and intense due to anthropogenic CO2 emissions. The global average temperature has already risen 1.2 degrees Celsius above pre-industrial levels, and the Indian subcontinent is particularly vulnerable. Delhi’s urban heat island effect, caused by concrete and asphalt absorbing heat during the day and releasing it at night, adds another layer of jeopardy.
Meanwhile, UK aid agencies are using the crisis to renew calls for increased climate adaptation funding. “The voices in Delhi are a stark reminder that we cannot afford to ignore the human cost of climate inaction,” said Dr. Rachel Jones, a spokesperson for Climate Action UK. “We need to shift from reactive disaster response to proactive investment in resilience: cooling centres, heat-resistant housing, and early warning systems that reach the most marginalised.”
The British government has pledged £11.6 billion in international climate finance over five years but adaptation projects receive only a fraction of that. Critics argue that wealthy nations, historically responsible for most carbon emissions, have a moral obligation to help vulnerable countries adapt.
There is also a growing recognition that adaptation and mitigation must go hand in hand. Even if we stopped emissions today, locked-in warming from past emissions will continue for decades. For every degree of warming, the atmosphere can hold 7% more water vapour, leading to more intense rainfall in some areas and deeper drought in others. The physics is unforgiving.
Technological solutions such as cool roofs, which reflect sunlight and reduce indoor temperatures by 2-3 degrees, are being piloted in Delhi. But scaling these interventions requires political will and funding. The International Energy Agency estimates that global investment in adaptation needs to reach $180 billion annually by 2030 to meet current and future risks.
As the heatwave continues, the choice for Delhi’s poor remains stark. Survival now means enduring the heat today. But without a rapid energy transition and targeted adaptation, survival will become increasingly untenable. The planet is warming; the data are unambiguous. The question is whether our collective response will match the scale of the crisis.
This is not a future problem. It is happening right now, on the streets of Delhi, and in the bodies of those who have no choice but to endure.
