Why does it always snow earlier in Daxinganling than in other places?

Daxinganling, located in the northeast border of China, is the main mountain system in Inner Mongolia Autonomous Region. The length from north to south is about1220km, which spans Jiageda Banner City in northern Heilongjiang Province, Hulunbeier City in Inner Mongolia and counties under the jurisdiction of Xing 'an League. It is the dividing line between Songliao Plain and Mongolian Plateau. Daxinganling is also an important ecological barrier in Northeast China and even North China. The hinterland of the central Daxing 'anling Mountains is located at latitude 4 1? ~54? And east longitude 1 16? ~ 128? Between, the area is about 39? . Covering an area of 8.24 million square kilometers, it has a humid and semi-humid climate in the cold temperate zone. The annual average temperature in this area is 2.5℃, the annual average temperature changes 1.0 ~ 3.8℃, the annual average precipitation is 386.7mm, the annual precipitation changes 296.4 ~ 5 18.3mm, and the precipitation is concentrated in June-August in summer, accounting for 74.3% of the annual rainfall.

Natural ecosystems such as forests and wetlands are more sensitive to climate change. Long-term climate change will inevitably lead to changes in the distribution pattern of natural ecosystems such as forests and wetlands. Daxinganling regional wetland is one of the most concentrated areas of high latitude swamps in China. Forests, wetlands and frozen stagnant water are interdependent and mutually restrictive. Daxinganling has a typical temperate forest ecological environment and the characteristics of surrounding cold wetlands. In the south of Daxing 'anling Mountains, wet grasslands are mainly distributed in cold and humid gentle slopes, flat watersheds or terraces. Swamp grassland is easy to develop into swamp in cold and humid environment, which is beneficial to the formation and development of wetland.

However, in recent years, due to global warming, the temperature in Daxing 'anling will rise. The trend of climate warming and drying is one of the main reasons for the atrophy and degradation of wetland ecosystem in Daxing' anling; In the future, the trend of climate warming and drying in Da 'an mountain area is obvious, which is consistent with the future northeast region. Daxinganling wetland ecosystem will be affected by climate warming and drought, which is relatively strong. Generally speaking, the future Daxinganling wetland ecosystem will still be threatened by the trend of climate warming and drought, and will face the trend of shrinking and serious degradation.