Super Typhoon Mangkhut is a flood threat for Hong Kong, but climate change will bring a lot worse

Super Typhoon Mangkhut is forecast to hit Hong Kong on Sunday. Have we learned from the past to minimise the threats?

On August 29, several districts in the New Territories experienced torrential rain and flash floods, even on an amber rainstorm warning. This led to severe flood damage to cars, and electrical equipment and appliances. Firefighters and volunteers had to evacuate animal shelters to save the creatures from drowning.

Thanks to its weather warning system and storm protections, Hong Kong stays reasonably prepared for floods, but recent events such as last year’s Typhoon Hato, which triggered the most severe No 10 signal and caused widespread flooding, showed that these measures may be inadequate.

Climate change will also make flooding more frequent and severe. By 2100, floods that would have occurred once every 50 years will return every three years or less – as a result of rising sea levels and changing rainfall patterns. Many cities around the world have now adopted flood protection standards against once-in-a-century floods; parts of the Netherlands can even withstand once-in-10,000-years floods. Without adequate safety measures, more than 687,000 people and HK$9.3 trillion of assets in Hong Kong are predicted to be at risk.