What are the impacts of human activities on this round of climate warming?

Judging from the current scientific cognition, the understanding that "man is the master of the earth" has almost evolved into a joke. In fact, human beings should treat the earth on which they live with a grateful heart. Ruth Campbell, an American astronaut who landed on the moon, was filled with love for the earth and happiness as a human being when he landed on the moon by Apollo: my strongest feeling when I landed on the moon was my deep love for the earth. Although the earth has shortcomings, it is suitable for us. As an advanced life, human beings should learn to grow in the perception of others.

/From club.china.com/, China Net Community

UN-HABITAT pointed out that at present, there are 335 1 cities in the world located in the coastal areas with low altitude (below 10 meters above sea level). If global warming causes sea levels to continue to rise, they will be affected to varying degrees. It is this 335 1 city that is home to more than 60% of the world's population and occupies an important political and economic position in various countries. Professor Liu Xiaohan, representative of the Earth Science Group of the International Scientific Committee on Antarctic Research in China, pointed out that by 2050 at the earliest, the Antarctic ice sheet may melt completely, the sea level will rise by nearly 70 meters, and the global coastal cities will be greatly threatened! "

In 2009, the United Nations IPCC submitted a report to the Copenhagen Climate Conference, which gathered 5,000 climate experts from all over the world to diagnose the global climate. According to the report, if the sea level rises 1 m in the future and the Arctic Ocean melts between 2020 and 2037, then two-thirds of the delta areas in the world will sink in the sea level rise, including the Mekong Delta in Viet Nam, the Irrawaddy Delta in Myanmar, the Ganges Delta in Bangladesh, and the most dangerous areas such as the Yellow River Delta, the Yangtze River Delta, the Pearl River Delta, the French Longhe Delta and the Egyptian Nile Delta in China.

According to the latest research report of the University of Colorado, two-thirds (22) of the 33 densely populated large delta areas in the world are facing the double threats of land subsidence and sea level rise. In the past 10 years, serious floods occurred in 85% of the large-scale delta areas around the world, resulting in the inundation of 260,000 square kilometers of land. If the sea level continues to rise at the current forecast rate, the flooded land area will increase by 50% in this century. According to the degree of threat, the delta is divided into five levels. The Yellow River Delta, the Yangtze River Delta and the Pearl River Delta in China have an area of about 1 0.6 million square kilometers and a population close to1100 million, making them the most serious. China Academy of Surveying and Mapping pointed out that the Pearl River Delta is the most affected area in China.

The Pearl River Delta is low-lying, and the elevation of most areas is lower than 1m, of which 1/4 land is 0.4m lower than the Pearl River datum (the height of a certain point relative to the datum), and about 13% land is lower than the sea level. The elevation of most areas such as Guangzhou, Foshan, Zhuhai, Zhongshan and Dongguan is about 0.5-2.0 meters at the datum level of the Pearl River. At present, many areas are protected by dikes. In 2007, the climate change assessment report of Guangdong Province said that according to the current situation, the sea level will rise by 30 cm in 2030, and the land of the Pearl River Delta 1 153 square kilometers may be flooded, among which Guangzhou, Zhuhai and Foshan are the most threatened. If there are no tidal protection facilities, the submerged area will reach 5545.69 square kilometers, and the scope will also be expanded to Zhongshan, Dongguan and other places.

In 2007, China's "National Assessment Report on Climate Change" said that in the past 100 years, the average surface temperature in China increased significantly, with a temperature increase range of about 0.5℃-0.8℃. In recent 50 years, the warming in China is particularly obvious. The average surface temperature increased by1.65,438+0℃, and the warming rate was 0.22℃/ 10 year, which was significantly higher than the global or northern hemisphere average warming rate in the same period. The average annual temperature in Guangdong is 0.21℃10 years, which is the same as the national average. From this point of view, the rapid warming in the Pearl River Delta in recent 50 years has made it the main warming area in China.

Dr. Du Yaodong, an expert in disaster assessment of China Meteorological Bureau, said that the future climate warming trend in Guangdong will be further intensified, which may be 65,438 0.5℃ by 2020 and 2.7℃ by 2050. This is not an alarmist. Due to global warming, the volume of seawater expands and glaciers melt, which accelerates the sea level rise along the coast of Guangdong and even around the world. At the same time, he also warned that sea level rise will increase the level of storm surge. In fact, in recent ten years, the frequency of strong storm surge along the coast of Guangdong has increased by 1.5 times. In 2008, Guangdong suffered a once-in-a-century storm surge brought by strong typhoon Hagupit.

Shanghai is the largest city in China. For a long time, Shanghai has been regarded as the key research object of the earth's climate problem. It not only uses Taihu Lake, but also lives by the sea and is vulnerable to various storm surges. Urban construction has brought a large number of high-rise buildings, underground traffic and over-exploitation of water sources, which makes it face the danger of sinking into the ground and floating out of the sea. In fact, global warming has greatly affected Shanghai. In the past 50 years, the urban temperature in Shanghai has risen by 2.35℃, which is more than twice that of the whole country in the same period, nearly four times that of the global data, and more obvious than other similar estuary cities in the world (such as Amsterdam, Houston, New Orleans, etc.). ).

As a part of the alluvial plain in the Yangtze River Delta, Shanghai is the central point of the north and south coasts of China, at the intersection of the Yangtze River and Qiantang River. At present, the average altitude in Shanghai is only about 1.8-3.5 meters, and the lowest point is only 0.9 1 meter. In recent 30 years, the sea level in Shanghai has risen by 1 15 mm, which is higher than the national average of 90 mm For example, many low-lying areas, such as Chongming Dongtan and Pudong Linhai, are showing a trend of less and less land area. If no corresponding measures are taken, some ecologically fragile areas in Shanghai will also face the danger of being flooded to varying degrees. The average sea level in Shanghai is 4 meters above sea level, while the sea level in Huangpu River has risen by more than 5 meters. If it continues to sink for 2m, Shanghai will immediately fall into a Wang Yang.

The World Wide Fund for Nature (WWF) reports that by 2050, the sea level along the coast of Shanghai will rise by 30 cm, and another scientific organization thinks the figure is 70 cm. According to the research of the State Oceanic Administration, if the sea level rises by 65cm under the condition of moisture-proof facilities, according to the highest tide level in history, seawater may flood 13% of the land along the Yangtze River Delta and Jiangsu coast, including Shanghai. In other words, most rich cities in the Yangtze River Delta will be flooded, including Shanghai, which is about 54,000 square kilometers, more than half of the whole Shanghai. Paul Brown, a former editor-in-chief of the Guardian's environmental edition and a freelance writer, believes that Shanghai is considered as one of the cities with high risk factors on the issue of sea level rise caused by global warming.

World Wide Fund for Nature (WWF) is one of the largest independent environmental protection organizations in the world. Since the establishment of 196 1, WWF has been committed to environmental protection, with nearly 5.2 million supporters around the world and active networks in more than 100 countries. The mission of WWF is to stop the deterioration of the natural environment of the earth and create a bright future in which human beings live in harmony with nature. To this end, we are committed to protecting the world's biodiversity, ensuring the sustainable use of renewable natural resources and promoting actions to reduce pollution and waste consumption.

The United Nations Intergovernmental Panel on Climate Change (IPCC) believes that the vulnerability of climate change has great heterogeneity in geographical space; Comprehensive vulnerability analysis shows that the most vulnerable areas are mainly distributed in Chongming Dongtan, Dongping National Forest Park, Sheshan National Forest Park and coastal buffer zone. Sub-vulnerable areas are mainly distributed in the northern part of Chongming Island, hengsha island, Changxing Island, Nanhuikou, Hangzhou Bay coastal tidal flat wetland and major water systems in Shanghai. Whether other areas belong to weak and fragile areas. Shanghai vulnerability index is positively correlated with temperature and precipitation, and future climate warming may make Shanghai more vulnerable.

Under the influence of global warming, the probability of precipitation disasters in Shanghai in the past 50 years has increased by 5.3 percentage points compared with the previous 50 years; The extreme maximum temperature began to rise in the late 1970s, especially in 2003, when the extreme high temperature of 39.6℃ appeared. The changes of temperature, precipitation and airflow aggravate the possibility of storm surge, and the losses caused by storm surge also increase. The possibility of extreme weather events like Hurricane New Orleans is increasing. Lin of the State Oceanic Administration said that sea level rise will aggravate marine disasters such as storm surge, coastal erosion, seawater intrusion, soil salinization and salt tide.

Wang, an academician of China Academy of Sciences and a professor of marine geology at Tongji University, said, "Global warming has caused sea level rise to become a worldwide problem; However, among the coastal cities in China, Shanghai and Tianjin are facing the most severe challenges, mainly because of land subsidence. " According to the media, land subsidence in China has become more and more serious in recent 20 years, spreading from Shanghai to the Yangtze River Delta, Pearl River Delta, Beijing-Tianjin-Tanggu and North China, and 95 cities are threatened by land subsidence. In 2002, the book "Shanghai Urban Geology Towards the Road of Sustainable Development" mentioned that during the 44 years from the first discovery of land subsidence in Shanghai in192/kloc-0 to 1965, the average subsidence in Shanghai was 1.69 m, with the worst point reaching 2.63 m and the subsidence area reaching/kl.

Reuters reported on June 5438+ 10, 2008 that in the 1970s, the Shanghai government actively reinjected groundwater, and the degree of land subsidence was obviously reduced, and the surface even rose. However, in the 1990s, Shanghai began to build in full swing, and the surface began to sink again. Although Shanghai is now taking measures to prevent over-pumping of groundwater, high-rise buildings like mushrooms after rain will lead to ground subsidence. Xu Shiyuan, a professor of geology at East China Normal University, said: "This problem is more serious in areas where groundwater is used more or high-rise buildings are dense." According to the statistics of Annapolis, an authoritative building information agency, there are about 10000 buildings in Shanghai which are higher than 10, and 80% of them were built in the recent 10 year.

Liu Shouqi of Shanghai Geological Society said that before 2000, the settlement rate in Shanghai was 6 mm, and now it has reached 10 mm. Since19,21,the cumulative settlement has exceeded 2 meters. The main reason is the over-exploitation of groundwater resources. Shanghai is a typical soft soil area. With the rapid development of the city, super-high-rise buildings have sprung up in soft soil areas, and with the pumping of groundwater, Shanghai has been declining. Since 1980, township enterprises in the surrounding areas of the Yangtze River Delta have mushroomed, and the scale of groundwater exploitation is expanding day by day. Land subsidence occurred in Suzhou-Wuxi-Changzhou area in Jiangsu province and Huzhou area in Hangjiahu area in Zhejiang province, which was connected with Shanghai in the region.

The bustling Shanghai has recorded the changes of China since ancient times, retained the unique Shanghai style of China, and played a leading role in the economic development of China. It is hard to imagine what Shanghai, as the financial center of China, would look like if it sank. A hundred years is not far away. How can cities that are predicted to sink, including Shanghai, turn the tide? Standing at the historical turning point of global climate change, how should these future Atlantis save itself? Plato told the world in Dialogue that "the price of wisdom is contradiction, which is a joke of life on the outlook on life."

The planet we live in is affectionately called "home" because it is she who gave birth to human beings. We know very little about this. After all, this is only a fleeting moment in the 4.6 billion-year history of the earth since the development of human enlightenment. But looking at the development of this "home", I can't help but feel that her existence is really wonderful. It seems to be accompanied by inherent periodicity and regularity, and it is so fragile and sensitive. From a long time ago, in a period, this law seemed to swing between balance and imbalance, and brought different results.

In ancient times, human beings told the vicissitudes of the earth with rough and emotional records, and even gave various predictions about the future, although the most scientific explanation could not be reached at that time. With the development of wisdom and technology, mankind can gradually unveil the veil of the earth. At the same time, successive disasters have prompted science to seek more reasonable answers. Qin Dahe, chairman of the National Climate Committee of China, pointed out in June 20 10 that global warming is an indisputable fact, not a wild guess! Regarding the concept of "global warming", many people think that global warming is an increase in temperature. In fact, global warming may not only lead to an increase in temperature, but also lead to a decrease in temperature, and the fluctuation range is large. In short, it will lead to a significant increase in extreme weather events.

20 10 March, Kuang Yaoqiu, Chinese Academy of Sciences, said that the general trend is still global warming, but the minimum temperature is decreasing and the maximum temperature is increasing, so the average temperature is still rising. The increase of greenhouse gas concentration in the atmosphere will not synchronize global warming, but will lead to climate extremes. Because greenhouse gases are likely to have a warming effect only in sunny areas. With the increase of greenhouse gas concentration, the greenhouse effect will be further enhanced, and the atmospheric circulation will change obviously: the increase of greenhouse effect in the solar irradiation area will lead to the increase of temperature, which will inevitably lead to the expansion of the atmosphere above it, which will inevitably lead to the compression and subsidence of the atmosphere in the area without solar irradiation, and the result of atmospheric compression and subsidence is that the weather will become cold. This statement is also the feedback mechanism after global warming, that is, the influence of greenhouse effect on atmospheric circulation and ocean circulation.

On March 26th, 2065438+00, Ren Fumin, chief expert of the National Climate Center, thought that the overall feeling was that extreme weather was increasing, but there was a lack of more historical data to prove it. Science cannot determine that a single event is directly related to global warming, so don't emphasize the inevitable connection between extreme weather and global warming. Global warming is just a big background. We can collect all these extreme weather events and analyze them as a whole to find out whether they are related to global warming. For individual events, it can only be said that it is caused by abnormal atmospheric circulation.

In the cold winter of 2009, Ren Fumin summarized four main influencing factors: first, the abnormal atmospheric circulation, the main body of cold air in the whole northern hemisphere moved out of the polar region, with the center in Siberia, resulting in a large area of abnormal cold; Second, El Nino is close to the central Pacific Ocean, which makes the seawater in the central and eastern parts extremely cold, so it has a cooling effect; Third, volcanic activity has been frequent in recent years 10, and volcanic ash acts as a barrier to the earth, which can reduce the radiation of the sun to the earth and reduce the temperature; Fourth, when the solar activity is strong, the external radiation is strong, and when the solar activity is weak, the external radiation is weak. The sunspot activity cycle is 1 1 year, which is at a low point in recent years and is also conducive to the cooling of the earth.

In fact, the scientific community has reached a consensus on the impact of atmospheric circulation on extreme climate, and the focus of debate is whether global warming will lead to changes in atmospheric circulation. Then, in the case that scientists don't have an answer and probably can't find it in a short time, the two hypotheses will exist forever. On the premise of looking at the two scientific conclusions objectively, does it mean that we can take it lightly or ignore the possibility that "global warming will cause changes in atmospheric circulation"? The answer is obviously no.

Only one day after the 20 10 Yushu earthquake, Chen Xuezhong, Institute of Geophysics, Seismological Bureau of China, expressed his views on the global earthquake. He believes that since the 8.7-magnitude earthquake in Indonesia in 2004, the world has entered an active period of earthquakes. At the same time, he also put forward a new view on the cause of the earthquake, that is, the change of the earth's rotation rate. Because the earth's lithosphere is composed of blocks with different sizes and qualities. When the earth's rotation rate changes, it will cause differences in the movement of these blocks. This differential movement may lead to three situations: rear-end collision, separation and friction between blocks, which may lead to earthquakes. Earthquake energy comes from kinetic energy lost when blocks collide or rub.

Because the rotation speed of the earth is different every day, it is necessary to find out the law. IERS, an international professional organization, began to record the daily rotation speed of the earth from 1962, and found that the rotation of the earth sometimes accelerates and sometimes decelerates, which has relative regularity. The period of long-term speed change is about 10 years. 1993 -2003, the earth's rotation was accelerating, and it has been decelerating since 2003; In a year,1-March and August-10 are in the period of earth deceleration, and April-July and1-12 are in the period of earth acceleration. He found that the proportion of earthquakes in March, April, August and September was obviously greater than the natural probability. Strong earthquakes are most likely to occur during the exchange period of acceleration and deceleration in a year.

At the same time, Zhou Fulin, an academician of China Academy of Engineering and an earthquake expert, also used statistical data to show that "the global earthquake has entered an active period". He said that since 2009, there have been 2.6 earthquakes of magnitude 7 or above every month in the world, compared with 1.6 in the last century. However, the centennial average of earthquakes of magnitude 7.7 or above is twice a year, and in the last nine months (May 2009 to April 20 10), there have been six earthquakes in the world. The global earthquake has entered a highly active period. He said that as far as China is concerned, China was in an active period of earthquakes in the 1960s and 1970s, and Xingtai earthquake and Haicheng earthquake occurred. 1976 after the Tangshan earthquake, it turned into a quiet period and became active again in the late 1990s. Generally speaking, the active period of earthquakes will last for ten to several decades. So it is not known when this activity will end.

Zhang Shaoquan, one of the experts who disagreed with the view that "global earthquakes have entered an active period", said on the day of Yushu earthquake that the frequent occurrence of global earthquakes can only show that there is strong seismic activity at present, but there is no unified standard in the industry on whether to enter an earthquake-prone period. He believes that these seismic activities always have a strong period and a weak period, because seismic activity is the inherent attribute of the earth itself, and earthquakes are the release ability of the earth and the symbol of its vitality. In the environment of high temperature and high pressure, and under the influence of external environment and planets, it is normal for the earth to release energy under various influences. And he stressed that because it is a "modern earthquake disaster", that is, due to the development of the city and economy, the urban population density is high, and once a major earthquake occurs, the impact will be greater.

We witnessed that the earth quietly launched one disaster after another, and human beings were caught off guard by one death after another. Under all this, the debate became pale and powerless. As an author named Luo Fei said, "Man is a child spoiled by the earth. He got the favor of the earth by accident and stood out among the children of the earth. Then, arrogant children think they are the cleverest and most capable. He just learned some skills and proudly called it science, thinking that science can do anything. Then I lost my awe and felt that I could stand on the top of the earth and do whatever I wanted. "

In the face of this ultimate question, do humans still insist on the so-called modern civilization and make great strides? Or the so-called interest struggle? The expression of human reverence for nature is to promote human speech to international dialogue, because it is not caused by one person, nor can a country solve it alone. Since lonely human beings have no power on the earth, responsible countries must cooperate on an equal footing in the face of this planet-level problem.

Once upon a time, we were so proud that we dared to declare to heaven and earth that human beings were the masters of all things. But today, in the face of the growing disaster on the earth, we know the fear of losing. Today, we can still control our own destiny to a great extent, but if we ignore this right today, it is also an obligation. Once we lose it, mankind will never embark on the road of self-help.

Scientists are more convinced than ever that human activities have affected the climate, and the resulting climate change has further intensified. Global warming has been destroying everything we have worked so hard for. As we said in "2℃ Changing the World", every rise of 1℃ will lead to the evil change and even destruction of the earth. The reality is that various extreme climatic and geological anomalies occur intensively. The 2007 assessment report of the United Nations Intergovernmental Panel on Climate Change (IPCC) officially pointed out that in the past 35 years, climate warming caused by human activities has had a significant impact on natural and biological systems.

What is worrying is far more than these visible facts. The predictions of many civilizations in the world invariably point out that 20 12 will be the year when the earth will return to the Yuan Dynasty. The critical moment is approaching step by step, and this topic has attracted the attention of the world more deeply. We don't know what will happen at 20 12, but the earth problems that are constantly being revealed at present are more and more clearly reminding people how to save themselves.

The smartest scientists in the world have called on different occasions that human beings are approaching the "irreversible point" of climate change step by step-2℃ higher than before the industrial revolution, and we must immediately reduce carbon dioxide emissions to slow down climate warming in this century and beyond. In view of the lagging response of the climate system to the concentration of atmospheric greenhouse gases, the best time to reduce emissions is today, and once the climate warming process exceeds a certain point, when the climate changes significantly, we want to reduce the temperature to the specified level.

According to Reuters's report on February 7th, 2006, Blair, then British Prime Minister, pointed out in his speech that it would be too late if important policies and decisions were not made on the issue of climate change in recent seven years. Blair said that there are only about three years left in this period. In addition, every year of delay, mankind will pay a greater visible economic cost. Take the loss of natural disasters caused by climate warming as an example. According to the report of the United Nations Environment Programme (UNEP) UNEP)2006, the natural disaster losses in 2005 reached an all-time high of 200 billion US dollars, and this figure is still developing in turn. By 2050, the annual economic loss will reach $300 billion. According to the forecast of the International Energy Agency, the cost of curbing catastrophic climate warming will increase by 500 billion dollars every year.

In a sense, we lost yesterday, but we must not lose the future. During the period before February 22, 20 12 and 12, meteorological disasters and geological disasters such as drought, blizzard, hail, super heat wave, debris flow, volcanic eruption, earthquake and tsunami will occur more frequently, which seems to sound an alarm for us. Although scientists are trying to smash the prediction of "20 12 doomsday", the deep damage caused by human activities to nature will not come true unless it is corrected.

You can hide in the first day, but you can't hide in the fifteenth. We can't escape from 20 12. Can we escape from 2016,2056 or 2 100? The prediction of world 10 has sounded the alarm of disaster for the earth around 20 12. No matter whether it is mysterious or absurd, it is no accident that the predictions of different historical periods are surprisingly coincident. Even if the clock on February 22, 20 12, 12 rings normally, even if the sun rises as usual that day, even if the apocalyptic prophecy of 10 can be judged as an apocalyptic lie of 10, people's mood is still not relaxed.

There is no need to clear the fog of history and erase the dust of time. Humans have felt the pain of the earth, and the alarm bells sounded by scientists in the past 20 years have never been questioned. Ground subsidence and sea level rise, plate changes, species extinction, all these are enough to throw human beings into the living world at will without blowing off dust! What's more, every precise combination of disasters on earth will not appear alone.

Looking back at the five mass extinctions in 540 million years, it is always the creatures who control the earth that are pushed to the guillotine. At present, the door of the "Sixth Great Extinction" era has gradually opened. Can man beat time? Can mankind become a tragic promoter of self-destruction without being greedy? Many scientists have sounded the clarion call for human self-help: if human beings can control the reins of greed, stop harming the earth and not only respect all human lives, then the road for human beings will be long and brilliant!

Judging from the current scientific cognition, the understanding that "man is the master of the earth" has almost evolved into a joke. In fact, human beings should look at the earth on which they live with a grateful heart. When American astronaut Ruth Campbell landed on the moon in Apollo, her heart was full of love for the earth and happiness as a human being: my strongest feeling when I landed on the moon was my deep love for the earth. Although the earth has shortcomings, it is suitable for us. As an advanced life, human beings should learn to grow in the perception of others.