GLOBAL CLIMATE NEWS: A rapidly intensifying El Niño event could significantly increase heat-related mortality across several parts of the world, with a new assessment projecting approximately 239,000 additional heat-related deaths between September 2026 and February 2027 compared with an average year.

The projection comes as unusually warm conditions in the tropical Pacific continue to strengthen and influence weather patterns across the globe. Researchers warn that the combination of El Niño and an already warmer climate could expose millions of people to more frequent and intense periods of extreme heat.

The assessment covers 24,378 regions worldwide and uses local relationships between temperature and mortality alongside seasonal temperature forecasts. Researchers compared the projected conditions with the 1996–2025 average to estimate the potential increase in heat-related deaths.

The projected impact is not expected to be evenly distributed. Countries and regions with higher exposure to extreme temperatures and more limited capacity to adapt are expected to face a larger share of the additional mortality burden.

The Sahel is projected to experience the largest regional increase, with an estimated 66,800 additional heat-related deaths during the six-month period. Nigeria alone accounts for an estimated 31,400 of those deaths.

India is also projected to face a substantial impact, with approximately 15,800 additional heat-related deaths during the September-to-February period. Researchers estimate that about 7,400 of India’s projected additional deaths could occur between December and February.

Indonesia is projected to record around 19,300 additional heat-related deaths, while the combined estimate for the Philippines, Vietnam, Thailand and Cambodia is approximately 19,400.

The assessment also points to unusually high temperatures over land during the coming months. Global land temperatures are projected to remain around 1.2 degrees Celsius above normal, while the number of extremely hot days could be approximately 44 percent higher than in a typical year.

The researchers emphasize that these figures are projections rather than confirmed deaths. Actual mortality will depend on how temperatures develop, local vulnerability, access to cooling and healthcare, and the effectiveness of heat-prevention measures.

The wider estimate becomes considerably larger when the period beginning in June 2026 is included. For June 2026 through February 2027, the assessment estimates approximately 451,000 additional heat-related deaths associated with the El Niño episode. The larger figure includes modeled impacts from months that have already passed and should not be interpreted as 451,000 deaths expected only during the coming six months.

The developing El Niño is also raising concerns beyond human health. Strong El Niño events can alter rainfall and temperature patterns, increasing the risk of drought, flooding, wildfires and agricultural disruption in different parts of the world.

For countries already experiencing high temperatures, additional warming could place pressure on electricity systems, water supplies, agriculture and healthcare services.

Researchers say there is still an opportunity to reduce the potential human toll. Early heat warnings, public communication, cooling centres, access to drinking water, protection for outdoor workers and targeted assistance for vulnerable populations can help communities prepare before extreme heat arrives.

The projections also underline a wider climate concern. Scientists have increasingly warned that natural climate variations such as El Niño can produce more severe consequences when they occur against a background of long-term human-driven warming.

The current event is therefore being closely monitored by climate and weather agencies around the world. Forecasts are expected to be updated as new temperature observations become available and the El Niño develops.

For governments and communities, the latest assessment provides an advance warning of where heat-related risks could become particularly severe. The coming months could test the effectiveness of early-warning systems and emergency preparedness measures as unusually warm conditions continue across many regions.