The heat index in Delhi has exceeded 43.5 degrees Celsius, a threshold that marks not just a meteorological milestone but a public health crisis in the making. For the capital of India, a city of 20 million, this is not an anomaly but a signal. The UK Met Office, known for its global climate modelling, has been called upon to assist in adaptation strategies.
The data is stark. The heat index, which combines temperature and humidity to measure perceived heat, has pushed into the 'danger' zone where heat-related illnesses become probable. Delhi's infrastructure, designed for a climate that no longer exists, is straining under the load. The city's power grid is buckling under the demands of air conditioning, water supplies are dwindling, and the urban heat island effect amplifies temperatures by up to 5°C in built-up areas.
The UK Met Office's involvement is a acknowledgment that no nation can tackle climate change in isolation. Their expertise in seasonal forecasting and attribution science will help Delhi anticipate and prepare for future heatwaves. But the physics is simple: warmer air holds more moisture, increasing the heat index. Until we reduce greenhouse gas emissions, these events will become more frequent and severe.
This is not a problem for next decade. It is now. The heat index in Delhi is a thermometer for the planet. And it is rising.
