In parts of the United States this month wind chills brought already Arctic temperatures down to minus 39 degrees Celsius. More than 20 people died as a result of the polar vortex.
Meanwhile, in Australia, thermometers soared to a high of 47 degrees in Adelaide. Amid the searing heat, the overuse of air conditioners caused widespread power failures as electrical grids struggled to cope with demand.
Worldwide, extreme weather events are increasing in frequency. Just last year, droughts and wildfires plagued California and Australia, while heat records were broken across Europe and North Africa.
Last year Hong Kong experienced its third hottest May as thermometers soared to a high of 36.7 degrees. Then the city was battered by the most intense tropical storm on record when Typhoon Mangkhut raged in September.
And in the past week, we recorded the hottest second and third days of Lunar New Year on record.
What does this tell us about climate change?
Climate change refers to fluctuations in global temperature trends that raise a host of other environmental concerns. Generally speaking, as greenhouse gas emissions intensify in the atmosphere, temperatures are pushed to extremes. Temperatures around the world are rising, and concentrations of carbon dioxide in the atmosphere are higher than they have been in 800,000 years.
According to the World Meteorological Organisation, the past four years have been the hottest since records began in 1850, and the warmest 20 years have all been in the past 22. The warming Arctic is pushing polar air down to places such as the American Midwest, which is unaccustomed to being hit by such winds.
While not all of this can be attributed to climate change, the shifts in the Earth’s atmosphere and elementary composition increase the likelihood of such extreme weather. At the World Economic Forum in 2018, “extreme weather events” were listed as the highest environmental risk in the “Global Risks Report”.
Where does Hong Kong stand in all this?
In the summer of 2017, five typhoon 8 warnings were issued, including the record-breaking Typhoon Hato. Earlier that year, Hong Kong was engulfed in a fog that concealed the city’s famous skyline, with visibility dropping to just 500 metres.
In March 2014 the city was hit by hailstones the size of golf balls – some of which smashed through the roof of Festival Walk shopping centre in Kowloon Tong.
The city’s changing climate is consistent with shifting patterns around the world. A humid subtropical climate, Hong Kong’s winter is mild, averaging 16 degrees in January, and summers are sticky, hot and rainy. But the onslaught of a warming planet has pushed the weather to extremes in recent years.
Our meteorological records date back to 1884. The lowest recorded temperature is minus 6 degrees at Tai Mo Shan in January 2016, and the highest 39 degrees in Tin Shui Wai in August 2017.
The increased moisture in the air, coupled with warming seas, raises the city’s humidity, the chances of heavy downpours and the frequency of tropical cyclones.
Officials predict that Hong Kong’s sea levels will increase by one metre by the end of the century, making typhoons an even bigger threat in our daily lives. Higher sea levels will also make the storm surges that come with typhoons worse, causing low-lying areas of the city to flood more often.
What is Hong Kong doing to combat this?
As part of China the city is a signatory of the 2016 Paris Agreement to tackle the world’s environmental crisis.
Hong Kong’s Environment Bureau published a Climate Action Plan 2030+ in 2017 that establishes how it will reduce its carbon emissions by 2030.
The government’s aim is to reduce the city’s carbon footprint by 26 to 36 per cent over the next 10 years. Broadly speaking, these mitigation efforts include using cleaner fuel, renewable energy, and increasing sustainability and efficiency in urban areas and transport.
Just 1 per cent of Hong Kong’s electricity comes from renewable sources, and the government says the city can only stretch to about 3 or 4 per cent.
The government has also urged the public to do its share in combating climate change. Otherwise, the extremes we have seen both locally and across the world are predicted to get worse.