BEIJING, August 2, 2018 (News Wires) - The North China Plain, home to nearly 400 million people, could become a life-threatening inferno during future heat waves if climate change continues apace, researchers have warned.
Soaring temperatures combined with high humidity - made worse by the region's dense irrigation network - means the China's breadbasket faces “the greatest risk to human life from rising temperatures of any location on Earth,” they said in a statement.
Megacities Beijing and Tianjin both fall within the densely populated plain, along with other major urban areas.
But it is tens of millions of farmers working outside that will be most at risk.
Even if humanity manages to slow the pace of global warming, hot spells across the region could, by century's end, exceed the human body's ability to cope, the scientists reported this week in the journal Nature Communications.
“This spot is going to be the hottest spot for deadly heatwaves in the future, especially under climate change,” said lead author MIT professor Elfatih Eltahir, who has published similar assessments of the Persian Gulf region and South Asia.
In China, heatwaves have become both more intense and more frequent since 1970, especially in the last 15 years.
Average temperatures have gone up 1.35 degrees Celsius (2.4 degrees Fahrenheit) since 1950, nearly double the average global increase.
But the human body's capacity to withstand extended bouts of heat also depends on how much moisture is in the air.
So-called “wet bulb” temperatures take humidity into account, providing a better measure of potential health impacts.
For perspiration to occur, air at the skin surface must be moister than the ambient air. The larger the difference, the more quickly the body can cool.
A sunburn, but inside the body
“But if the wet bulb temperature exceeds the human body's skin temperature of 35 C, perspiration no longer works as a cooling mechanism,” explained Jeremy Pal, a professor at Seaver College of Science and Engineering in Los Angeles who has collaborated with Eltahir in the past but did not take part in the new study.
“The body will quickly overheat, resulting in death.”
Experts estimate that a healthy adult may not survive outdoors at “wet bulb” 35 C for more than six hours.
Humidity is key.
At 55 per cent relative humidity, for example, it would take a searing air temperature of 44.4 C (112 F) to reach the 35 C wet bulb threshold.
But at 85 per cent humidity, an outdoor temperature of 37.8 C (100 F) is sufficient to surpass the limit of human tolerance.
“When it is both very hot and humid outside, heat in the body cannot be expelled,” noted Camilo Mora, a professor at the University of Hawaii who developed a model last year to calculate deadly heat days under different climate change scenarios.
“This creates a condition called 'heat citotoxicity' that is damaging to many organs,” he told AFP at the time.
“It's like a sunburn, but inside the body.”
Eltahir and Suchul Kang a researcher at the Center for Environmental Sensing and Modeling in Singapore, used climate models that best matched temperature records over the last three decades to forecast heatwaves.
They looked at two possible futures.
One - often called the “business-as-usual” scenario - assumes that climate change will continue unabated, while the other allows that humanity can bend down the curve of greenhouse gas emissions enough to cap warming at about 3 C, compared to mid-19th century levels.
Surprisingly, they found that the North China Plain's irrigation system adds about half a degree Celsius to future warming, under either scenario.
“Irrigation exacerbates the impact of climate change,” Eltahir said.
Unless drastic measures are taken to limit the greenhouse gas emissions warming the globe, “the North China Plain is likely to experience deadly heatwaves with wet bulb temperatures exceeding the threshold defining what Chinese farmers may tolerate,” he added.
The 196-nation Paris Agreement calls for capping the rise in temperature at 2 C, and 1.5 C if possible.
BEIJING, March 29 (Reuters) - The number of pollution sources in China has increased by more than half in eight years, the environment ministry said on Thursday as it embarks on a nationwide survey to determine the damage done by more than 30 years of untrammeled growth.
The announcement from the newly minted Ministry of Ecology and Environment (MEE) underlines the challenges facing China, in its fifth year of a war on air, water and soil pollution, as it tries crack down on data fraud and improve monitoring.
The government is currently conducting a second nationwide "environmental census" aimed at identifying pollution threats throughout the country. The first was published in 2010.
"The goal for the census is to do thorough data collection so that it can reflect the extent of the pollution," Hong Yaxiong, the head of ministry's pollution survey office, told reporters at the first regular briefing since the beefed-up ministry was created this month.
The environment ministry absorbed new duties formerly held by the land, water and agriculture ministries as part of the biggest government shake-up in years. It will also now be in charge of climate change and carbon emissions.
The new census is due to be completed in 2019. According to preliminary estimates, the total number of pollution sources now stands at 9 million, including 7.4 million industrial sources, 1 million in rural areas and 0.5 million from urban locations, Hong said.
The first census conducted by the National Bureau of Statistics from 2007 to 2009, uncovered 5.9 million sources of pollution nationwide, with the industrial provinces of Guangdong, Jiangsu and Zhejiang at the top of the list.
The survey also identified 209.8 billion tonnes of waste water, 63.7 trillion cubic metres of waste gas emissions and 3.852 billion tonnes of industrial solid waste nationwide.
Started last year, the second census will widen its scope to include industrial parks, rural pollution sources, boilers, municipal and waste water outlets, and it will also survey soil pollution sources such as mercury, cadmium or lead.
BEIJING, March 19 (AP) — A US-trained economist was appointed on Monday to succeed the longtime governor of China's central bank, Zhou Xiaochuan, at a time when the ruling Communist Party is trying to reduce financial risks and surging debt.
The elevation of Yi Gang, a two-decade veteran of the central bank, to head the People's Bank of China was in a slate of promotions approved by China's ceremonial legislature of finance and economic officials as President Xi Jinping tightens control over government.
Also Monday, the National People's Congress endorsed the appointment of Liu He, Xi's economic adviser, to a post as vice premier, where he is expected to oversee economic reform.