Snow Cave in China

Yantai and Weihai are located in the northeast of Shandong Peninsula. Compared with inland and coastal areas of Wei Yan, they are veritable "snow nests". The topic is closely related to the geographical location and topographical features of these two cities. According to the meteorological statistics of yantai laishan airport (1992-2006), the cold current snowfall in winter accounts for 78% of the total snowfall, and the average number of cold current snowfall days is about 39 days. This cold current snowfall is a unique weather phenomenon in the coastal areas of the Yellow Sea and Bohai Sea in winter in China, especially in Yantai and northern Weihai of Shandong Peninsula, especially in the coastal areas with low mountains and hills in the northern part of Shandong Peninsula (located in the southern part of Bohai Sea), and the snowfall in the areas south of the hills decreases rapidly. The average precipitation on the peninsula is 20% ~ 30% more than that in other parts of the province. The average precipitation days in the northeast of the peninsula are 16 ~ 18d, while those in the inland are only about 10d. According to the monthly precipitation distribution of Theory of Three Represents Station in the northeast, south and inland of Shandong Province, the total precipitation in Yantai and Weihai in winter is 365,438+0% more than that in Qingdao in the south of the peninsula, and twice as much as that in Jinan. The number of days of precipitation is twice that of Qingdao and Jinan respectively, and the maximum number of days of precipitation is 65438+February, and that of Yantai and Weihai is twice that of Jinan. Yantai and Weihai have never experienced zero precipitation, while Qingdao and Jinan have experienced zero precipitation. All these data show that the precipitation in the northeast of the peninsula is obviously localized.

Generally speaking, there are two reasons for the frequent heavy snow in winter in Wei Yan: First, the strong cold air from Siberia goes south, which is constantly dumped by the terrain shear of Liaodong Peninsula and Shandong Peninsula on the ground, resulting in a large amount of snowfall for a long time. Second, when cold air goes south from Northwest Road, it will pass through Bohai Sea. In winter, the west branch of the warm current to Malaysia transports warm water from the open sea to the Yellow Sea and Bohai Sea, and the surface water temperature shows a high temperature tongue extending from the South Yellow Sea to the Bohai Sea. The central part of Bohai Sea is located at the top of warm tongue. Because the surface temperature of Bohai Sea is higher than that of air, the warm sea surface transports a lot of heat and water vapor to the dry and cold air layer, and the large sea temperature difference makes its temperature stratification unstable, thus forming snowfall. From the mechanism of snowfall and the intensity of cold air, the temperature of warm water surface also has an influence on cold flow snowfall. The snowfall mechanism of cold current snowfall is similar to the Great Lakes effect blizzard in the United States. According to the relevant research results in the United States, the lake temperature difference is the most important condition for lake effect snowfall. For Wei Yan, Bohai Bay is equivalent to the "Great Lakes" of the United States, that is, "inland lakes". The mountainous areas of Yantai and Weihai also provide the possibility for cold air to rise and then form snowfall. Affected by cold air in winter, the snowfall in Yantai Weihai often has the characteristics of strong persistence and intensity. The so-called persistence means that it usually lasts for several days, and many of them last for several weeks. Snow in Yantai is not an anecdote, and neither is heavy snow and blizzard. The snowfall in Weihai, Yantai shows the characteristics of more than two ends in winter and moderate reduction, that is, the snowfall in early winter and early spring is increasing. The reason is that snowfall is easy to form in early winter due to the large temperature difference between the ground and the ocean. During the Spring Festival on New Year's Day, due to the coldest weather, the temperature difference between the ground and the sea is the smallest, so it is not easy to form snowfall. At the end of spring, the temperature difference between the ground and the sea surface widens, and under the influence of cold air, it is also easy to form snowfall. The first snow in Yantai is usually from the middle and late June to the early February every year 165438+, and the last snow will fall 4,2010 in the snow in March or even at the end of April every year, and the last snow in April is 199 1.

Heavy snowfall is also a feature of snowfall in Wei Yan, which continued from February 3, 2005 to the beginning of 2006. The snowfall in Zhifu District of Yantai is 80.3mm, and the snow depth is 1.2m, which is the largest continuous snowfall in Yantai since 196 1 recorded meteorological data. Roads are covered with layers of snow, vehicles are moving at painfully slow speed, highways in China are intermittently closed, and some flights at the airport are forced to stop, which makes it difficult for people to travel in snowstorms and strong winds. ...

Anyone who has lived in snowy Yantai has had such an experience: in Yantai, as long as the north wind blows in winter, a cloud can snow. The wonder we often see is the "sun snow". One side is the sun in the sky, but it doesn't affect the falling of snowflakes. Therefore, the locals call this kind of snow "sun snow".

"Lei Zhen in winter, rain and snow in summer, dare to leave you", among which "Lei Zhen in winter" is called an impossible meteorological landscape in literature, but in Yantai, "Lei Zhen in winter" will also appear when it snows in winter, but this situation is rare. Take the heavy snow in Yantai from 65438+February 2 to 65438+February 0, 2005 as an example. On the positive side, the frequent heavy snow in winter in Wei Yan can alleviate the cold in winter. Because wheat is in the growing period, frequent heavy snowfall is equivalent to watering the winter wheat in the peninsula in time. At the same time, it is very beneficial to increase urban and rural groundwater reserves, alleviate the contradiction of water shortage in spring, improve soil moisture in wheat fields and ensure the safe winter of wheat.

Yantai and Weihai are coastal tourist cities, and the proportion of tourism in urban GDP is much higher than that in inland cities. For the northern coastal tourist cities, summer is generally the peak season for tourism, but after the weather turns cold, the tourism industry is bleak. However, in Wei Yan area, this unique phenomenon attracts many tourists because of the snow scene and coastal cities. Some experts even pointed out that Yantai is like China's "Hokkaido", which is covered with snow in winter and has become the city's winter tourist card.

Of course, there are disadvantages. After the heavy snow in winter, urban traffic becomes extremely crowded, and a large amount of snow melts, which may also lead to water accumulation or freezing in some sections. In the long-term work, departments at all levels in Yantai and Weihai have formed a winter special plan mechanism. As soon as the whole city enters winter, a large number of snow removal forces will be ready. They always pay attention to the weather, forecast rain and snow, and start emergency plans. After the heavy snow, large snow sweepers will be seen working back and forth in the streets and alleys of Yantai, and citizens have also developed the habit of snow removal. After the snow, everyone threw themselves into the battle to clear the snow.