China’s key urban centres, including the capital Beijing and its most populous city, Shanghai, are expected to face hotter and longer summers, as well as wetter rainy months, a new Greenpeace study mapping extreme weather conditions due to climate change warned on Wednesday.
Greenpeace East Asia said the risk of extreme heat and rainfall is now highest in densely-populated city centres but is growing fast in communities that are becoming more urban on the outskirts of the country’s large cities.
That could mean more exposure to dangerous heatwaves for the elderly and those working outdoors as well as heavier flooding in cities such as Shanghai, Liu Junyan, the climate and energy project leader for Greenpeace in Beijing, said as he called on the authorities to adopt more effective measures to prepare for such conditions.
“Urban areas still don’t fully understand the variety of changes, and which ones will impact which areas and how, enough to be ready for them,” Liu told Al Jazeera.
The study found that Beijing is experiencing the “greatest increase” in average temperature, rising at a rate of 0.32 degrees Celsius (0.58 degrees Fahrenheit) every 10 years, with the frequency of heatwaves increasing “considerably” since 2000.
Factoring in the expected peak of global emissions around 2040, the increase in temperature in some parts of Beijing could exceed 2.6C (4.7F) by 2100, and summers would become longer by 28 days, the study added.
“For Beijing, we know this temperature rise will look like more days with temperatures at 35 degrees [Celcius] or hotter temperatures,” Liu said.
“Crucially, a 2.6-degree rise means more exposure to heatwaves. The elderly are at risk, as are people doing strenuous outdoor labour, like construction workers and delivery drivers.”
In February this year, the temperature shot up to 25.5C (78F) in some areas – the highest recorded during the winter season – according to several weather monitors and news reports.
Greenpeace said summers would also lengthen by between 24 and 28 days in Shanghai and to more than 40 days in the southern Guangdong province. Some parts of the Shanghai and Guangdong province would also experience a more than 25 percent rise in extreme rainfall, while the area’s northwest would experience more drought.
The Greenpeace warnings follow similar studies showing an increased risk in China from extreme heat related to climate change.
A July 2018 study published in the journal Nature Communications noted that the frequency and intensity of heatwaves observed in China have “increased significantly” during the last 50 years. It also warned that as many as 400 million people in northern China, including Beijing, could be affected by deadly heatwaves by 2100.
A December 2020 report published by The Lancet, a respected medical journal, said that heatwave-related mortality in China had risen “by a factor of four from 1990 to 2019, reaching 26,800 deaths in 2019.”
On Monday, the journal Frontiers in Sustainable Cities said Beijing and Shanghai were among 23 Chinese cities in the top 25 urban hubs around the world that produce 52 percent of the climate-warming gases annually.
The list also includes Tokyo and Moscow. Cities in the US, Europe and Australia still lead in the list in per capita terms, although several Chinese cities such as Yinchuan and Dalian as well as Urumqi in Xinjiang also recorded per capita emissions approaching the level of developed nations, according to the authors from Sun Yat-sen University and a Guangdong province pollution monitor both in Guangzhou.
In September 2020, President Xi Jinping said China aimed for carbon dioxide emissions to peak before 2030 and net-zero emissions before 2060, as part of the country’s commitment to curb climate change.
The sprawling urban area of Guangzhou, on China’s southern coast. figured prominently in the Greenpeace East Asia study, which found that 73 of the 98 heat waves in the past 60 years in the area occurred after 1998.
Guangzhou’s average number of days with extreme heat (35C/95F or higher) has risen from 16.5 days per year to 23.7 days per year since then, it noted.
The Greenpeace study predicted that the average temperature change for the southernmost areas of the Guangdong province would be up to 2C (35.6F), effectively extending summer by more than 40 days.
In May of this year, rising temperatures led to an electricity shortage in Guangdong, prompting local authorities to curb power usage, thus also affecting the productivity of the manufacturing sector.
“We were informed to stop production for two days a week, according to the electricity limitation policies,” a staff member surnamed Miao at a copper factory in the province told the state-run Global Times newspaper. As a result, the factory’s scheduled delivery dates were delayed.
From extreme heat to devastating floods
From extreme heat, Guangdong province is also predicted to face more intense flooding during rainy months. In the southeastern part of the province, where the city of Shenzhen is located, extreme rain would increase dramatically, with the hardest hit areas having more than 25 percent more extreme rainfall, Greenpeace said.
Similarly, Shanghai and its region, where the Yangtze Delta flows also face the dilemma of extreme rainfall leading to considerable flooding.
From 1961 to 2019, the average accumulated rainfall for the Shanghai Yangtze Delta was 1225.6 mm (48.3 inches). Although it has fluctuated over the years, Greenpeace said that it has been “steadily increasing” at an overall rate of 34.6 mm (1.4 inches) every 10 years.
The year with the highest rainfall was 2016, with 1666.9 mm (65.6 inches) of total accumulated rainfall.
According to Greenpeace, the cities of Shanghai, Suzhou, Wuxi, Changzhou, and Ningbo – cities that have the highest density in terms of population and economy – are particularly at risk of hazards from extreme rainfall.
“Flooding is already a serious problem in Shanghai, and we can expect more flooding in the future and more devastating impacts from floods,” said Liu.
In 2020, severe flooding affected many cities along the Yangtze River, Asia’s longest river. According to government data, more than 140 people were killed, 38 million others were affected and 28,000 homes destroyed in the worst flooding in the country in 30 years.
Other parts of China that have not historically experienced much flooding, like Hotan, also known as Hetian, in Xinjiang, were also hit, Liu noted.
The Shanghai metropolis and surrounding urbanising areas have also seen rising temperatures.
In Hangzhou just southwest of Shanghai, temperatures have reached 35C (95F) or above 429 times in the last 60 years, with 177 (41 percent of the total) occurring since 2001.
The highest recorded temperature at the Hangzhou Weather Station was 41.6C (106.88F) in 2013, followed by 41.3C Celcius (106.34F) in 2017.
Greenpeace’s Liu said big Chinese cities should anticipate and prepare for weather interruptions, adding there was a need for “scientific and systematic investigation” on the effect of climate change.
He also said that smaller cities, where extreme weather risk is growing the fastest, also need to be better prepared for different types of climate risks.
“Cities need comprehensive monitoring to develop early warning systems for vulnerable communities and vital infrastructure. The interface of science and policy will determine whether vulnerable communities can receive proper attention and care in the face of this risk,” Liu said.