Hong Kong issues heat warning for summer solstice amid climate change warnings

“As heat continues, people should remain vigilant to avoid heat stroke or other ailments associated with very hot weather and take care of their health.”

According to the forecast, temperatures could rise to 34 degrees on Saturday and Sunday.

Friday’s 33 degrees matched the temperature of the previous day, when the city recorded its hottest day of the year so far, surpassing the value reached just earlier in the week.

Large-scale heat waves also occurred in the USA, Mexico and Greece, among others.

Leung Wing-mo, former deputy director of the observatory, said climate change plays a “crucial role” in the city’s very hot days and the increasing number of heat waves.

He added that any 0.1 degree increase in temperature would lead to a “sharp increase” in the number of heatwaves, citing a recent report by the UN’s Intergovernmental Panel on Climate Change.

“Heat waves are, without exception, weather extremes that are strongly associated with global warming,” he said.

Between 2010 and 2019, Hong Kong recorded an average of about 27 very hot days per year, according to the Post Office’s calculations. In the last three years, that number has risen to over 50.

According to the observatory’s latest climate forecasts, Hong Kong could experience up to 80 very hot days by mid-century at peak greenhouse gas emissions.

Leung added that the summer solstice also contributed to hot temperatures in the city.

The summer solstice is the time when the sun rises over the Tropic of Capricorn, which Leung says is at a similar latitude to Hong Kong.

“This means that the sun is almost directly over Hong Kong, so the solar intensity is at its strongest at this time of year,” he said, adding that the normally wet and cloudy weather in June would normally mitigate the impact.

But he also said there could be fewer very hot days overall this year compared to 2023 as the world transitions from El Niño to La Niña, two climate patterns in the Pacific Ocean that can affect weather around the world.

“The La Niña effect is cooling the sea water in the eastern equatorial Pacific, so I don’t expect as many very hot days as last year,” he said.

The Center for Health Protection also called on the public to be particularly careful of the elderly, pregnant women and children and to be alert to any symptoms of heat stroke.

“The public should carry and drink plenty of water to prevent dehydration during outdoor activities,” a spokesperson for the center said.

“People who engage in strenuous outdoor activities should avoid caffeinated beverages such as coffee and tea, as well as alcohol, as these accelerate water loss through the urinary tract.”

At 8:50 a.m., the Department of Labor also issued a yellow workplace heat stress alert, indicating high levels of heat stress in certain work environments.

Outdoor workers are reminded to take necessary hot weather precautions in accordance with department guidelines.

To reduce the risk of heat stroke among employees, appropriate rest breaks should be scheduled every hour wherever practically possible, a department spokesman said.

People who experience symptoms of heat-related illness such as headache, dizziness, thirst and nausea should rest in a cool and shady place, drink water and inform employers and supervisors so that they can take immediate action, he added.

The last heat warning was issued on June 13 and lasted more than 3½ hours.