Is the earth getting cold or hot?

The disappearance of winter means warmer weather, which is really terrible. The low-lying areas along the Pacific Ocean and the Indian Ocean will be submerged by seawater and become a Wang Yang. Thousands of residents who used to live there had to emigrate to other countries. It has been calculated that when all the ice and snow melt, the sea level will rise by about 60 meters, which means that all places below 60 meters above sea level, including those below the 20th floor of Manhattan skyscraper in new york, will be submerged by sea water. ...

The climate is warming and the sea level is rising. Is this alarmist? No, some scientists have found evidence of land subsidence caused by sea level rise. Compared with the same period of last century, Shanghai, Guangzhou, Tianjin and other big cities have sunk by about 15cm.

Global temperature records can also prove the trend of climate warming. According to the statistics of the British Meteorological Department, 1988 is the highest temperature in the last hundred years. At the end of this century, the annual average temperature rose six times, all in the 1980s. By the early 1990s, the global annual average temperature had risen by 0.59℃, which indicated that the earth was obviously warming.

So why is the earth getting warmer? Scientists believe that the influence of human activities on climate is becoming more and more serious. The world releases1200 million tons of carbon dioxide into the sky every year.

Carbon dioxide has a peculiar effect. It can absorb a lot of heat in the surface and lower layers of the atmosphere and prevent heat from being lost to the air, just like glass in a greenhouse. So scientists use the term greenhouse effect to explain the role of carbon dioxide. The higher the carbon dioxide content in the atmosphere, the more obvious the trend of climate warming.

More seriously, some trace gases in the atmosphere have a "greenhouse effect" far more serious than carbon dioxide. These trace gases include: methane produced by organic matter decay, exhaust gas emitted by automobiles, and nitrous oxide released by nitrogen fertilizer in soil ... Although these gases are not many at present, they have strong heat absorption ability and can amplify the greenhouse effect of carbon dioxide.

In addition, there are more and more artificial heat effects in cities. With the increasing scale of urban construction and population, the urban temperature is 0.5 ~ 1℃ higher than that in the suburbs. This phenomenon is called the heat island effect.

The above reasons seem to be enough to prove that the earth is warming. However, while some scientists are scrambling to put forward measures to control the greenhouse effect, others have put forward tit-for-tat opinions.

Umbrella effect

In recent years, scholars who attack the theory of climate warming have emerged one after another. Some scientists have published their research results, pointing out that the earth is developing in the direction of low temperature and humidity. The view that the earth is warming is just a misunderstanding of unknown nature.

Some experts in geology, geography, paleontology and archaeology in the United States believe that the view of "warming theory" is based on the statistical data of meteorological observation stations, and 97.5% of the data of meteorological observation stations are taken from cities and their surrounding areas. It is not difficult to see that there is man-made warming around the city, so the warming theory lacks a strong basis.

According to the satellite temperature measurement, NASA scientists proved that the average temperature of the earth did not increase or even decrease from 1979 to 1988. The temperature in the northern hemisphere 10 increased slightly, but the temperature in the southern hemisphere decreased. Generally speaking, the earth is getting cold.

The United States Department of Agriculture has been tracking research for many years and found that the earth is cooling down. They made a detailed analysis of the data of more than 65,438+0,200 meteorological observation stations. Since 1.920, the temperature has only increased in big cities, but decreased in urban suburbs and rural areas.

Meteorologists in China also believe that the meteorological data in China also show a downward trend in temperature.

The earth is getting cold. What is its theoretical basis? Scientists have made all kinds of interesting answers.

Some people say that our earth will enter the "refrigerator" for some time every tens of thousands of years. This is called the ice age in the history of the earth. By then, the whole world will be wrapped in silver, even the equator is no exception. The earth has experienced a warm period of nearly 65438+100000 years, and humans seem to hear the footsteps of glaciers rushing in.

Some scientists say that cold weather is related to the "parasol effect" on the earth. What is the sunshade effect? This refers to the impact of smoke and dust in the earth's atmosphere. Since World War II, the number of volcanic eruptions has increased from 16 to 18, with an average of 37-40 times a year. From 1880 to 1970, the artificial smoke and dust in the northern hemisphere increased by three times, and the smoke and dust emitted by industries, automobiles, stoves, etc.

Scientists have different opinions on the prediction of climate warming or cooling, and there are great differences. What Ed Briant, a professor at Warren University in Australia, said seems to make sense. He said, "The climate is changing, but the reason for the change is natural, not man-made." He said that the climate will only become more changeable. For example, Britain has just experienced the coldest winter in history, followed by the warmest spring and autumn. This is just the fluctuation of natural climate.

According to him, whether it is the greenhouse effect or the sunshade effect, these human factors have affected the temperature of the earth, but they cannot control the general trend of temperature changes. Is the earth getting cold or hot? It is still an interesting mystery, but with the diligent exploration of scientists, all mankind will be able to withstand the test of climate change and meet the challenge of bad weather.