North China, where almost half China’s population lives and most wheat and corn are grown, is facing serious water crisis.
Since the late 1990s severe and extreme droughts have frequently dropped by and drought affected area has been increasing by 3.72% decade-1 in the past five decades, posing great challenges for regional sustainable development.
Scientists have been concerned that if climate continues to warm in the future, there is a high confidence level that drought over North China will continue to increase.
Thus, it is of great importance to identify the drivers and dynamic mechanisms of North China drought in order to improve drought prediction and better water management.
A recent study published in Journal of Climate by scientists from the Institute of Atmospheric Physics at Chinese Academy of Sciences, Met Office Hadley Centre and Beijing Climate Center revealed the large-scale dynamic drivers of the prolonged spring-summer drought (PSSD) over North China, where prolonged drought tends to onset in spring and persists to summer with severe societal impacts.
Their study shows that seven of the selected eight North China PSSD events occurred when La Niña transited to El Niño with a negative North Pacific Oscillation (NPO) phase in preceding winter.
Consequently, sea surface temperature anomalies of El Niño in summer suppress Indian monsoon rainfall, triggering the tropospheric temperature cooling over East Asia through a circumglobal teleconnection along the East Asia upper-level westerly jet.
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Drought in Northern China Is Worst on Record, Officials Say.
Officials governing a large area of northern China say their region is suffering from the worst drought on record, leading to crops wilting and farmers and herders growing desperate to get water to farmlands, grasslands, animals and their households.
In recent years, Chinese scientists have attributed extreme weather patterns in China, and especially in northern China, to climate change.
The region of Inner Mongolia and its residents have been hit especially hard by wide fluctuations in the weather.
The United States is historically the world’s largest emitter of greenhouse gases, while China is currently the largest one.
Another large municipal area, Tongliao, has also been severely affected.
Photographs by Xinhua, the state news agency, show crops in dry soil and farmers spraying their fields with water.
At the time, 5.5 million people had joined in efforts to alleviate the drought, Mr. Chen said.
The Chinese government has made great efforts to try to halt or turn back the growth of deserts in northern China, and especially in Inner Mongolia.
The Chinese government has also tried to limit the movements of herders, saying their animals are turning grasslands into desert.

Process will be time-consuming and expensive: experts The contaminated pits recently found in North China are symptomatic of a larger problem, but the central government is stepping up efforts to curb water pollution across the country although the process is hard and time-consuming, experts said Monday.
China’s environmental authorities moved faster this time than before, with an immediate investigation, quickly arranged treatment plan and timely updates about the situation, according to Li.
The Ministry of Environmental Protection (MEP) launched a probe with the Hebei provincial government on the pits on Wednesday morning and confirmed that they were polluted by the afternoon.
The two pits were caused by digging years ago and were polluted in 2013 by illegal pouring of sulfuric acid, said the ministry, citing Dacheng government.
It would cost around 200 million yuan ($29 million) to treat the pollution from the 170,000-square-meter pit in Hebei, The Beijing News report said, citing industrial experts.
Water pollution treatment is difficult because the process involves many economic interests, said Bai Ou, a Beijing-based industrial expert.
China’s environmental laws are not comprehensive at the moment, and the central government is expected to put forward more effective rules, according to Bai.
More efforts "It is quite urgent to treat water pollution, but the process is difficult and will take many decades, based on similar experience in other countries like Japan," said Li.
With the development of the Jingjinji area (Beijing-Tianjin-Hebei region), sewerage treatment is not merely the responsibility of Hebei Province or Tianjin Municipality, and it involves more joint efforts to cover wider areas, Bai said, adding that this effort would have to apply not only in North China, but the whole country.
North China suffers from many forms of pollution, affecting water, soil and air quality due to the large volume of heavily polluting industries in the region, including mining, steel and coal, experts said, noting that the central and local governments are expected to increase efforts to curb the pollution.

Poison sewage pits in north China cause widespread water pollution.
Sewage pits are known to pollute groundwater, making it undrinkable.
CGTN’s Ning Hong reports.
Poisoned dark water is left to dry in the open air.
Ponds like these stretch a long distance and cover a vast area.
Locals said such ponds have been here for decades.
One resident said these ponds are the result of chemical plants that used to be located in the area.
And even though they’re gone now, the pollution remains.
Just a kilometer away is a small town called Nanfu.
There is no other source of water to be had, and most villagers have no choice but to continue drinking polluted water.

Ministry asks for quick action to mitigate effects.
China’s Ministry of Environmental Protection (MEP) on Wednesday confirmed there are two large pits of sewage in North China, urging the local government to conduct examination of underground water and ease the impact on the neighborhood.
Xiang Chun, head of the NGO, told the Global Times that the two pits in Dacheng county are located in suburban areas, while the one in Jinghai district in Tianjin, which covers an area of 150,000 square meters, is in the middle of farmland.
According to the MEP, Dacheng government said that the two pits were caused by digging years ago and was polluted in 2013 by illegal pouring of sulfuric acid.
The government has been dealing with the polluted pits all the time, but the pollution control work hasn’t been done yet.
These pits have been there for almost six years, but they did not cause us any inconvenience because they are nowhere near residential areas, a villager surnamed Chen from Zhaofu township told the Global Times on Wednesday.
Water in these pits is rust-colored and in some areas, the water’s pH level has already reached 1, said Xiang.
The pH scale measures the acidity or alkalinity of a liquid, and ranges from 0 to 14, with 7 being neutral and anything below 7 acidic.
In 2014, an industry owner surnamed Li in East China’s Anhui Province was sentenced to six months in prison and fined 10,000 yuan for using sewage pit to discharge pollutants, because his behavior severely damaged the environment, the China Environment News reported in 2015.
Groundwater pollution is more serious in North China than other parts of the country because the ground water level in this area is relatively low, which makes it easier for the pollutants to reach groundwater, Ma said.

China has 20 percent of the world’s population but less than 6 percent of the groundwater.
Desalination could be another solution.
The resultant dependence on and over-extraction of groundwater are having severe impacts on Beijing, including subsidence.
Long Di, a researcher at Tsinghua University’s Institute of Hydrology and Water Resources, says: "Subsidence is a slow but progressive disaster, and it is irreversible.
The problem is particularly acute in Chaoyang district, which borders Beijing’s eastern suburbs－areas that are rapidly expanding with dense, high-rise buildings.
What makes the problem more challenging is that many buildings in Beijing’s rapidly subsiding districts are far taller.
One example is California’s 2015 water shortage.
California also encouraged municipalities to actively manage demand, and many imposed surcharges on individual users who exceeded stipulated limits.
China’s demand profile for water does not closely resemble California’s; both markets have high usage for agriculture (64 percent in China and 80 percent in California), but China’s manufacturing activity as a share of economic output is larger than California’s.
This is a crucial step in aggressively addressing groundwater depletion in urban areas, including Beijing.