The winter of 2021 is a cold winter. Generally speaking, if the year is affected by the El Ni?o phenomenon, the winter may be mild. On the contrary, if a La Ni?a phenomenon occurs, the winter may be cold, which means it will be colder than previous winters.

Referring to meteorological concepts such as cold currents, cold fronts, and cold air, climate experts from the China Meteorological Administration divided the phenomenon of cold and warm winter into warm winter and cold winter, that is, the entire winter in a certain area in a certain year (national The average temperature in winter (from December of the previous year to February of the following year) is higher than the normal value or the climatic average (the normal value is generally taken as the average of the past 30 years. Since 2002, my country has used the 30-year period from 1971 to 2000 in accordance with the provisions of the WMO. When the annual average value is taken as the normal value), the area in that year is called a warm winter, otherwise it is called a cold winter.

Introduction

Previously, the National Climate Center has stated that a weak to moderate "La Ni?a event" will form this winter. Forecasts show that the cold air affecting our country this winter will be frequent and strong, and the temperature in the central and eastern regions will generally be colder. Among them, Liaoning, central Inner Mongolia, Beijing, Tianjin, Hebei, Shanxi, northern Shaanxi, northern Henan, Shandong, and northern Xinjiang will be 1℃-2℃ lower.