Why is global warming suddenly cold in winter?

In recent years, the topic of "global warming" has been widely known, but in winter, the records of low-temperature snow and ice weather have been rewritten again and again, whether in China or other countries.

20 13 12 15 A cold wave hit the Middle East, and the Egyptian capital Cairo ushered in the first snow since 190 1. At the beginning of 20 12, heavy snow fell in Europe, and Venice, a water city, was rarely frozen.

At the beginning of 2009 1 1, the cold current set the earliest record of the first snow in many provinces and cities in China.

On June 5438+February, 2008, a once-in-50-year snowstorm occurred in Tianjin, China.

In early 2008, a large-scale freezing disaster occurred in southern China. This cold current has also brought the first snow in 100 years to Iraq in the Middle East, and the worst snowstorm in the Russian Far East in 130 years.

In March 2007, a once-in-56 year heavy snow fell in Shenyang, China.

From June 5438 to October 2006 10, the temperature in Europe dropped, with the coldest winter in the Czech Republic in 66 years and the lowest temperature in Moscow in 79 years.

In the cold wave and winter in Leng Xue, some people who don't know will inevitably have such questions. It is said that global warming, why will it get cold in winter? Is "global warming" a pseudoscience that attracts public attention?

In fact, global warming is a popular saying. The phenomenon of abnormal cold in winter in the northern hemisphere can be explained by the change of ocean current model after global warming. Under normal circumstances, the ocean currents in the ocean will circulate around the world due to the differences of seawater temperature and salinity in different cities, driven by the "temperature-salt circulation". Shallow and hot low-latitude surface seawater moves towards the polar regions, and in the process, it continuously releases its contained heat. After reaching the high-latitude waters, it becomes cold and high-salinity seawater, sinks into the deep sea, and then turns back to the low-latitude areas in the form of deep-sea ocean currents, bringing coolness to the local area. The circulation process of ocean currents can bring the heat near the equator to cold high latitudes and neutralize the heat difference between high and low latitudes. With the increasing global warming, the heat regulation function of ocean current circulation is destroyed. Because after global warming, polar glaciers melt a lot, and the melted fresh water is directly injected into high-latitude Haicheng, which reduces the salinity of local seawater and reduces the amount of seawater sinking into the deep sea. The ocean current originally driven by salinity difference will slow down or even stop, and the heat exchange mechanism of ocean current will fail. Heat is no longer brought from low latitudes to high latitudes, but concentrated near the equator. In this way, the high latitudes will be colder, resulting in colder winters in the middle and high latitudes of the northern hemisphere.

So is "global warming" an exaggeration? It is a scientific and reasonable index to use the global average surface temperature to indicate the climate state. According to the assessment report of the United Nations Intergovernmental Panel on Climate Change (IPCC), among the 12 years with the highest global average surface temperature since 1850,1year is 19952006 (1996). Further, the last 50 years of the 20th century were the warmest 50 years in the past 1300 years. It can be seen that the phenomenon of global warming is an indisputable fact.

Generally speaking, the weather conditions around the world vary greatly, and the climate in the same area will fluctuate in different years. Therefore, the general trend of "global warming" should not be questioned by the snowstorm and severe cold in some areas in winter, otherwise it would be like modeling the blind.