Climate change: Hong Kong needs heat-protection policies with teeth

El Nino may have officially ended, but Hong Kong continues to break temperature records, with deadly consequences. A 56-year-old hiker passed away in June after being found unconscious, showing signs of heatstroke. We often associate extreme heat with deserts and droughts, but humidity can make heatwaves exceptionally deadly.

You may have heard of how drinking hot drinks can cool you: it works by making you sweat, which then evaporates, taking heat away. This, however, depends on the humidity – the more humid the air, the less sweat can evaporate. On hot, humid days, our sweat just clings to our skin and fails to cool us.

When our bodies cannot cool down, it can lead to heatstroke. A study published in 2022 suggests the maximum wet-bulb temperature – when the air is water-saturated, and sweat cannot evaporate – we can tolerate is at around 31 degrees Celsius.

What does it mean for us? For many in Hong Kong, turning on the air conditioning sounds like a simple solution. Those that have to work outdoors however – such as construction, cleaning, and delivery workers – are not as lucky. Sectors with an ageing workforce are also a concern. While the Labour Department has recently updated its heatstroke prevention guidance, it is still non-binding.

Climate change will continue to expose us to more extreme temperatures and weather after El Nino. Heat protection policies must be mandatory and have teeth to make workplaces safe. This includes providing water breaks, shading, rest periods and more to avoid heat stress. Beyond the private sector, the government must help vulnerable and low-income households to stay cool, while educating the public on how to cope with extreme heat and humidity.

Even if we mitigate climate change today, the impacts will not end overnight. We need climate adaptation to build resilience and safeguard public health as extreme weather intensifies in the coming decades.