Beijing Average Daily Pollutant Concentrations
(micrograms per cubic meter)
TSP SO2 NOx
1999 364 80 140
Pct Chg vs. 1998 -4 -33 -8
Daily Standard 300 150 100
Yearly Standard 200 60 50
World Health Org.
guideline 90 40
Source: Beijing Environmental Protection Bureau; standards are China level
II limits (applied to residential areas) for daily and annual exposure; WHO
guidelines are for annual exposure.
Sandstorms hit northwestern China's Gansu Province and North China's
Inner Mongolia Autonomous Region on the first day of the new century.
According to Sun Landong, a meteorologist with the Lanzhou Meteorology
Observatory, visibility was less than 100 metres in Minqin, a Gansu
county that nears Inner Mongolia, due to sand.
When visibility drops to less than 1 kilometre, it is termed a
sandstorm, said a senior technician with the Central Meteorology
Observatory.
The sandstorm in Minqin blew up dust in neighbouring towns, such as
Baiyin, Wuwei, Jinchang and Lanzhou, the capital city of Gansu
Province.
Dust-laden winds also swept into Beijing.
Brought by northwesterlies blowing speeds of more than 20 metres per
second, dust first reached the capital's suburbs at 7 am, downtown
areas at 9 am.
The winds, which died down during the night, brought the temperature
down to as low as minus 8 C and saw the suspension of scheduled flights
from the city's airport.
It is quite rare for sandstorms, which are frequent between March and
June, to occur in winter, when the earth is frozen, according to Wang
Xiaoyun, head of the Beijing Meteorology Observatory.
The sandstorms in Gansu and Inner Mongolia do not necessarily mean
there will be more of them in the spring than last year, when they were
rampant, but Beijing is taking the issue very seriously.
According to a blueprint mapped out by the Ministry of Water Resources,
the State Development Planning Commission, the State Forestry
Administration and the State Environmental Protection Administration,
Beijing will pour more than 6 billion yuan (US$725 million) into
curbing sandstorms in the capital and has already set up a special team
to ascertain what causes them.
Most cities in the east of North China were covered by thick fog
yesterday, but meteorologists said the fog will dissipate today.
However, there will be fog today in many parts of Southwest China,
including eastern Guizhou Province, Sichuan Province, Chongqing
Municipality and Hubei Province.
A meteorologist with the China Central Meteorological Observatory said
that stationary weather fronts and heavy moisture in the air are the
main causes of the thick fog.
Beijing, Tianjin, western parts of Shandong, Hubei, and Hunan and
northern parts of Jiangxi Province all had fog yesterday.
The expert explained that when water particles in the air cannot
evaporate because of the lack of air movement, they coagulate, forming
fog.
Though not in itself pollution, fog does aggravate it. The stationary
air mass and thick moisture block the dispersal of suspended particles
and other contaminants in the air, he said.
Cold currents are expected to visit Beijing and North China today, and
strong northerly winds of force 4 to 5 may blow away much of the
moisture and suspended particles, chasing away the fog and improving
visibility.
Temperatures in the region will also see a slight drop following the
entry of the cold currents.
The expert noted that fog is common in the winter.
"Fog has been less frequent this year than last year, but it is within
the normal range," the expert said.
The fog was not heavy in Beijing yesterday, and flight schedules at
Beijing Capital International Airport were operating normally.
In the city there were traffic jams at rush hours yesterday, and wet
road conditions slowed traffic along Beijing's third and fourth ring
roads.
Experts with the Beijing Environment Protection Bureau said yesterday
that pollution was expected to be aggravated, but conditions were
generally much better than they were last spring.
In 2000, Beijing's pollution index shot up to 300 on foggy days, while
the normal index is about 100.
This winter, most heating systems in residential areas were upgraded to
gas or low-sulphur coal.
The official pollution index for yesterday was unavailable at the time
of publication.
The heavy fog that blanketed North China yesterday morning is a natural
weather phenomenon in this season.
That's according to experts at the Central Meteorological Observatory,
who did not want to be named. The fog will gradually disperse starting
this afternoon, they said.
On Wednesday, Beijing saw mild spring breezes and sunshine.
According to the experts, the heavy fog not only appeared in most areas
in the North China plain, but also in the southern tip of Northeast
China. Visibility in some areas of Beijing and Tianjin municipalities,
and Hebei, Shandong and Henan provinces is just 500 metres.
The meteorological cloud chart also shows that there has been heavy fog
in areas like Siberia, said the experts.
They explained that now, as the weather starts to become warmer in
North China and is coupled with more rainfall and more humidity, the
region is prone to fog and also a slight drop in temperature.
In Beijing yesterday, it drizzled in some districts around 8 am. On
Wednesday night, there was a northeastern wind, carrying a warm humid
air current from Bohai Bay and the Yellow Sea to North China.
This further increased humidity so when the temperature went down at
night, the conditions were ripe for heavy fog, the experts noted.
Gong Xuezhong, a senior engineer with Beijing Municipal Meteorological
Observatory, also said that heavy fog most often occurs in Beijing in
spring and autumn. On Wednesday night, Gong said the weather was clear
to begin with, with just a few clouds in Beijing and nearby areas.
But at that time, below 1,500 metres, a stronger, warm and humid air
current slowly moved northwards, resulting in the heavy fog yesterday
morning.
Weather forecasts from the Central Meteorological Observatory predict
there will be a cold air current from the Northeast this afternoon, and
with the wind, the heavy fog that blanketed Beijing will gradually
disappear.
An early warning system for sandstorms will be put into operation
today, and related information will be made available via television
and the Internet.
The new forecast service was been made possible with the help of a
nationwide monitoring and forecast system against sandstorms.
A trial run of the system will start today to accumulate more accurate
information about possible sandstorms, said Li Huang, deputy director
of the China Meteorological Administration.
With the use of satellites, radar, sounding balloons and other
meteorological devices, the system can trace the development of
sandstorms and provide details of sandstorms such as where it will hit.
Experts predict sandstorms will not visit North China frequently this
year. North China's Inner Mongolia Autonomous Region and Hebei Province
have been important sources of sandstorms in previous years. Yet a
snowy winter this year has moisturized the earth surface and held sand
down.
Blizzards blanketed Xilingol League, Hulun Buir League and Alxa League
in Inner Mongolia this winter, causing heavy damage.
In Chengde, a city north of Beijing in Hebei Province, snowfalls were
50 per cent higher than average.
If rain falls in these places in March, Beijing can expect a spring
without sandstorms.
China has made efforts to fight sandstorms, which have frequented
northern parts of the country in recent years. China's top legislature,
the National People's Congress, is currently drafting an
anti-desertification law.
Strong winds bringing dust and sand swept across Beijing on Monday
night, the third time such weather has hit the capital this year.
Beijing has had sandstorms before on January 1 and last Saturday,
according to the Beijing Meteorological Observatory.
Visibility on Monday night was down to 1.4 kilometres, which is close
to the 1-kilometre mark usual during sandstorms, according to the
observatory.
Strong sandstorms hit Beijing several times last spring. Such weather
is mainly caused by strong wind that has been particularly rampant in
recent days, according to Zhang Mingying, an engineer at Beijing
Meteorological Observatory.
This wind blew up sand and dust from bare ground, such as fields and
construction sites, explained Zhang.
The situation on Monday night in Beijing was made worse by sand and
dust blown from North China's Inner Mongolia Autonomous Region, which
also had widespread sandstorms on Monday, Zhang added.
According to a report from China News Agency yesterday, the autonomous
region has been hit by sandstorms three times recently.
Judging from current conditions, the sandstorms might be stronger this
year than last year, said Zhang.
"This is because there has been more cold air this year than last," he
said.
Recent environmental efforts in Beijing, such as planting trees and
introducing gas furnaces, has, to some extent, reduced the effect of
sandstorms, said Zhang, adding strong winds caused the numerous storms
last year.
According to Chinese Academy of Sciences experts, most of the dust and sand blows in from northern Beijing, northern Hebei Province, and Inner Mongolia. They blame the contract responsibility system, which began in the early 1980's, for encouraging farmers to convert grasslands into farms, many of which have subsequently turned into dustbowls. The drought of the past several years also makes it easier for winds to stir up a sandstorm. City people need to invest in environmental protection by supporting the planting of grass and trees in the rapidly expanding desert north of the city, conclude the scientists. (Sanlian Life Weekly, February 2001)
Most of North China was hit by sandstorms yesterday for the fifth time
this year.
Sandstorms have now become a frequent occurrence much earlier in the
year than formerly.
China's Central Meteorological Observatory yesterday issued a warning
that North China - including Beijing and Tianjin, Northwest China's
Shaanxi Province - East China's Shandong Province and Central China's
Henan Province will experience sandstorms or drifting sand today.
Heavy sandstorms will also hit central parts of the Inner Mongolia
Autonomous Region and northern parts of Hebei Province, said the
observatory.
After three days of high temperatures, the sky over Beijing was turned
grey by sands blow from the Inner Mongolia Autonomous Region.
Beijing's hot weather and little rain have made the land drier and
produced more dust than usual, said Li Tingfu, an expert from the
Beijing Meteorological Observatory. Floating sands yesterday were blown
with winds of force 5 to 6.
But contradicting the Central Meteorological Observatory's predictions,
Li said Beijing would be free of sandstorms today, with winds of force
4 expected tomorrow.
Beijing saw its highest temperature for mid-March in 50 years on
Tuesday, when the mercury 23.5 C.
The Central Meteorological Observatory said temperatures in North China
will drop sharply after tomorrow, and areas in Northeast China will not
see temperatures rise until the end of March.
After several days of straight dips in the mercury, Beijing is expected
to warm up today, with the temperature reaching 12 C.
Although the temperature is still low compared with last week, when
temperatures shot over 20, it has started to rise, according to the
Central Meteorological Observatory.
The temperature in Beijing dropped 15 degrees within the past few days
and locals, who had been sporting their spring wardrobes, had to slip
into their woolies again.
The temperature drop was the result of an intrusion of extremely cold
air from Siberia, which is moving southeastward, according to Zhang
Mingying of the Beijing Meteorological Observatory.
"People had been enjoying the unseasonably high temperatures from March
13, so they felt especially cold when the temperature dropped," he
said.
The discomfort was exacerbated by the fact that central heating plants
had shut down last week and indoor temperatures were down to their
lowest levels since winter.
In spring, temperature changes are usually frequent and sudden in
northern China, and people should be careful not to catch cold in this
period, according to experts.
In most parts of the north, temperatures nosedived 6 to 10 degrees.
You're all ready for a day out with your family, perhaps a walk in the
park or a weekend bike ride through the city.
Then you see the white haze in the air and realize being outside isn't
going to be much of a picnic.
An innovative new air-quality forecast system in major Chinese cities
can now help you plan around such disappointments.
The Beijing-based China National Environmental Monitoring Centre
yesterday started issuing predictions of air quality on a trial basis
in 25 cities, including Shanghai, Chongqing and Tianjin. More cities
will be added, including Beijing, as the system is set up there, centre
engineer Tong Yanchao said
In the system, air quality, based largely on the air pollution index,
is ranked at different levels, including perfect, good and slightly
polluted.
The centre will not publicize the forecast during the trial period,
Tong said.
But by June 5, researchers hope, forecasts for 47 cities for the
following day will be released via China Central Television and other
media.
Tong and his colleagues will receive air quality statistics provided by
environmental monitoring stations and meteorological observatories in
each city.
They will then confer with the Central Meteorological Observatory and
devise a prediction. The air quality forecast will not only tell people
whether the air on the next day is fit for going out but also urge
cities to take measures to improve air quality, Tong said.
The trial period is required by the State Environmental Protection
Administration and China Meteorological Administration.
To keep a close watch on air pollution and develop ideas for future
air-quality improvement policies, the State Environmental Protection
Administration demanded in 1997 that key cities issue air-quality
reports each week.
Meanwhile, a piercing essay in Southern Weekend by Chang Ping entitled "The Key Lies Outside the Sand Storm Problem Itself," points to over-grazing and excessive farming as the key factors causing dust storms in Inner Mongolia and other source locales. The journalist in turn links environmentally irrational over-use of land resources in the region to short-term profit incentives operating in an unregulated market, while raising the difficulty of turning back the clock now that herder societies have undergone dramatic changes to adapt to the new order. Chang concludes, "sandstorms are a social problem, not a technical problem" -- because addressing the problems of population increase, over-cutting, over-grazing, over-farming, and poor water resource conservation will require social engineering, not simple technical solutions. The underlying issues, he adds, are mistaken policies, mismanagement, failure to balance overall regional interests. This means, "The real battle is a battle against ourselves."
The recorded instances of dust storms in Beijing have grow significantly in the second half of the 20th Century, from 5 times in the 1950's, 8 in the 1960's, 13 in the 1970's, 14 in the 1980's, 23 in the 1990's. There were 12 dust storms just in the year 2000, and 6 already in 2001 -- including a major dust storm on New Year's Day, perhaps as a harbinger of the new Millennium. Sandstorms have been occurring earlier and earlier each year. At the same time, the pace of desertification has accelerated. On average, 1560 square kilometers was lost to desert each year in the 1950's and 1960's, but this pace grew to 2100 square kilometers per year in the 1970's and 1980s's, and 2460 square kilometers per year in the 1990's. Chinese experts estimate annual economic losses in China due to blowing dust and sand total about 54 billion RMB ($6.5 billion).
Most dust storms reaching Beijing originate in territory northwest of the city; much of this area was originally grassland, converted to farmland using methods that turned out to be unsustainable, resulting in conditions similar to the "Oklahoma Dustbowl" that arose in the south-central United States in the 1930's.
China has been frequently able to provide relatively accurate and timely forecasts for sandstorms raging across the country's northern regions, particularly the drought-prone Northwest, in recent years, according to a leading weather official. Li Huang, deputy director of China Meteorological Administration (CMA) said over the weekend that this year the Central Meteorological Station, under the CMA, has for the first time brought sandstorm forecasts into its regular weather forecast this spring. This information was relayed to the public via the media. So far this year, the CMS has succeeded in predicting 16 sandstorms 24 to 48 hours ahead of their occurrences, Li confirmed. Statistics from the CMA indicate that by mid-May this year, sandstorms have appeared 18 times, blowing sand or dust in the North, Northwest, and parts of Northeast China. No casualties were reported. Sandstorms are strong windstorms, especially in semi-arid areas neighbouring deserts, that carry clouds of sand or dust, reducing visibility drastically, the CMA's experts say. The sand and dust usually causes serious air pollution, difficulties in everyday life, and even casualties and economic losses. To tackle the problem, China set up its State-level sandstorm monitoring and alarm system on March 1, the beginning of the period of bad weather. The system consists of 24-hour observation by ground meteorological stations across the country and remote sensing and data transmission by meteorological satellites. Li urged his agencies throughout China to make further efforts to improve sandstorm early warning systems and carry out a series of research projects to promote sandstorm forecast technology. World climate changes and the droughts in China over the past years are major reasons for more sandstorms, Li said. At the same time, spreading desertification caused by overlogging or overgrazing, the random-use of water resources and large-scale construction projects for rapid urbanization have also resulted in bad weather. Although China may face a new period of frequently occurring sandstorms, Li is confident that a series of effective counter-measures, including massive afforestation throughout China and turning lots of farmland into forests or grassland in western regions can help reduce the damage caused by sand or dust storms in the coming years.
China is suffering persistent drought over more than 23.3 million hectares of its land, the most widespread drought since 1990, which has already scorched millions of hectares of summer crops and unplanted farmland. The spring drought, which has lasted for nearly 100 days, has mainly hit Northeast China, most areas along the Yellow River and Huaihe River and Southwest China, according to the latest report of the State Flood-Control and Drought Prevention Headquarters in Beijing. The prolonged dry spell has also brought a shortage of drinking water for more than 16 million people and 12 million head of livestock, which are mainly in mountainous areas of Southwest China and in erosion-prone areas of the loess plateau in Northwest China, the mountainous areas of the Luliang Mountains in North China's Shanxi Province and the Taihang Mountains in Shanxi and Hebei provinces. When asked about the main causes of the drought this year, officials with the headquarters said that less rain than usual fell in most parts of China this spring. It is reported that rainfall decreased from 30 to 90 per cent in central and southern parts of Northeast China, North China, most areas along the Yellow River and Huaihe River, eastern parts of Northwest China, in Southwest China's Sichuan and Yunnan provinces. It has also been noted that reservoirs in North China and Northeast China do not have sufficient water to fight the drought. For instance, water levels in the reservoirs in Northeast China's Liaoning and Jilin provinces had dropped 46 per cent and 45 per cent respectively by the beginning of May, from levels at the same time in high flow years. Continuous sand-laden winds this spring in North China also worsened the drought conditions in this area by seriously sucking away the soil's moisture content. Drought prevention officials said summer grain crops are also being affected by the drought. A total of 227,000 hectares planted in summer crops will bear nothing, with Southwest China's Sichuan and Yunnan provinces having suffered most from the drought. In North China, it is a foregone conclusion that wheat production will also be affected by drought, as the wheat is in its heading period and in the milk, which is the most important stage of its growth. Experts are advising farmers to provide as much water to their fields as they can, to help the crops ripen, as there has long been little rainfall in this area. Active measures have been adopted by local governments of drought-stricken areas to alleviate the present disaster.