Why is winter getting longer and longer now, is it obviously very cold or so cold?

In the winter of 20 12, the temperature is cold and long, which is mainly affected by La Nina phenomenon. Affected by La Nina phenomenon, the water temperature in the equatorial eastern Pacific is low, and the meridional circulation in East Asia is abnormal, which leads to the northerly airflow prevailing in northern China since spring, while the warm and humid airflow in southeast China is relatively weak. Therefore, strong cold waves and strong winds frequently occur in the north.

La Nina means "La Nina" in Spanish? A "-"little girl, saint "means the reverse of El Ni? o phenomenon, also known as" anti-El Ni? o "or" cold event ". It refers to the abnormal drop of water temperature in the eastern Pacific near the equator, which is characterized by the obvious cooling of the eastern Pacific and the global climate chaos, and always appears after the El Ni? o phenomenon.

The motion of the ocean surface is mainly constrained by the sea surface wind. Because of the existence of trade winds, a large amount of warm water is blown to the equatorial western Pacific Ocean and blown away in the equatorial eastern Pacific Ocean, which is mainly supplemented by cold water below the sea surface. The SST in the equatorial eastern Pacific is obviously lower than that in the western Pacific. When the trade winds strengthen, the upwelling phenomenon of deep seawater in the equatorial eastern Pacific becomes more intense, resulting in abnormally low sea surface temperature, which makes the airflow in the equatorial eastern Pacific sink, while the upward movement of the airflow in the equatorial western Pacific intensifies, which is conducive to the strengthening of the trade winds, thus further aggravating the development of cold water in the equatorial eastern Pacific and triggering the so-called La Nina phenomenon.