Lethal humidity is on the rise, and it’s creating a real threat to populations, particularly in Indonesia. Dr. Robert Glasser, a researcher from the Australian Strategic Policy Institute, highlights that increasing heat and humidity are stripping away our body’s primary cooling methods. This can lead to serious health risks.
Heat stress is already a leading cause of death. In fact, the Australian government notes that heatwaves annually result in more fatalities than any other natural disasters—taking hundreds of lives each year. The most vulnerable groups are children and the elderly.
Dr. Glasser draws a striking comparison: “Every year, heat kills more Australians than the Vietnam War did—about five times more.” In Australia, the Northern Territory faces the greatest danger as heat and humidity climb. But Indonesia, situated right next door, is ground zero for these risks. It already deals with high humidity during both wet and dry seasons.
“It’s remarkable how many climate threats Indonesia faces,” Glasser says. The country experiences the world’s fastest sea level rise and is increasingly prone to natural disasters, many of which are worsened by climate change.
Policymakers in Australia must gear up for these looming challenges. Glasser warns that we might see more people displaced due to disasters or face food insecurity as climate conditions worsen.
When high humidity meets soaring temperatures, it overwhelms the body’s cooling mechanisms. As a result, the body sends blood away from internal organs to the skin, which can lead to severe outcomes, including organ failure. A 2010 study indicated that humans can’t survive over six hours at a “wet bulb temperature” of 35 degrees Celsius. Today, regions in Southeast Asia are already exceeding dangerous humidity levels for several months each year.
Dr. Glasser’s report, titled *Lethal Humidity and the Systemic Risks of Climate Change*, warns that as temperatures increase, tens of millions will be exposed to dangerous humidity. It suggests that by the end of this century, 50-75% of the global population could face this life-threatening condition.
He emphasizes that older adults, in particular, are at a much higher risk than younger people, with humidity tolerance levels that are significantly lower. Andrew Forrest, founder of the Mindaroo Foundation, supports urgent action on this issue. “High humidity doesn’t just make heat uncomfortable; it can push entire regions past human survival limits,” he states.
Glasser urges that we need more focus on how climate change will impact livability and highlighted the importance of adaptation strategies for vulnerable coastal cities. “We can reduce risks in Australia, but we cannot ignore the threats outside our borders,” he warns.
This isn’t just about the environment—it affects every part of society. As we move forward, we must act decisively to slow this impending crisis and safeguard countless lives.
For further reading, see the details in Dr. Glasser’s report [here](https://www.aspi.org.au/report/lethal-humidity-and-systemic-risks-climate-change) and a related study by *PNAS* on human survival thresholds in extreme conditions.
