Why is the strongest dusty weather a warning and a revelation?

On May 4th, Beijing Meteorological Observatory issued the first blue warning of dust this year.

On that day, Beijing was hit by the worst dusty weather this spring, and the PM 10 hour concentration once broke 2000 μ g/m3. Around yesterday evening, the dusty weather in Beijing gradually weakened and the impact tended to end. The Central Meteorological Observatory predicts that from the night of the 5th to the 6th, there will be sandstorms or dusty weather in parts of southern Xinjiang Basin, northwestern Qinghai, Inner Mongolia, central and eastern Gansu, southern Hebei, Shandong, Henan, northern Jiangsu and Anhui, among which there will be sandstorms in eastern Inner Mongolia.

This is also the strongest sandstorm weather process in northern China this year.

Dust mainly comes from two directions, one is the northwest of Xinjiang, Qinghai and Gansu, and the other is the west of Inner Mongolia and the south-central part of Mongolia. Two dust streams were transported from an altitude of 5000 meters, and settled to form floating dust after approaching Beijing. The "foreign dust" here means that the dust mainly comes from Beijing and surrounding provinces, but also from Mongolia. Finding the source of dust will contribute to the accurate diagnosis and effective treatment of diseases.

The dust in Beijing was the most serious in the 1950s.

The average number of dusty days in spring is as high as 26 days; In the 1960s and 1980s, the average number of dust days was 10 ~ 20 days; In the 1990s, it dropped significantly, and the average number of dust days was about 5 days. From 200 1 to 20 16, the average number of dust days remained at the level of 3 ~ 7 days. According to experts' analysis, since the 1990s, the average number of sandstorm days in Beijing in spring has obviously decreased, mainly due to the joint action of human control and climate factors, which has significantly improved the local environment in Shayuan area. Among them, the desert closest to Beijing and Kubuqi Desert in Inner Mongolia, once one of the three major sandstorm sources in Beijing, have made outstanding achievements in sand prevention and control, which has played a very key role in reducing the number of sandstorm days in Beijing and reducing the scale and impact of sandstorms.

Combating desertification is a serious challenge facing China.

This is also a major problem facing the world today. In this context, the achievements and experience of sand control in Kubuqi area in the past 30 years have aroused great interest from the international community, and the United Nations Environment Programme has even set up an international desert forum in Kubuqi, which is held every two years. Zhang Shigang, the representative of the United Nations Environment Programme in China, said that the success of Kubuqi model led by Yili Resources Group, a leading local enterprise, lies in the introduction of PPP cooperation model, which has driven more than 654.38 million farmers and herdsmen out of poverty through land leasing, equity sharing, tourism development and modern agriculture. In this virtuous circle, the initial goal is to control sand, so as to promote grass planting, medicinal materials, livestock and poultry, photovoltaic, ecological restoration and other industries, and through the ultimate goal of controlling sand, focus on the comprehensive control effect of "Kubuqi model".