Issues related to global warming

Global warming in the global warming paper refers to the phenomenon of rising temperatures in the earth's atmosphere and oceans over a period of time. The reasons revealed in the global warming paper mainly refer to the temperature rise caused by human factors. Currently, it is believed worldwide that the main reason is probably due to excessive emissions of greenhouse gases (representing the gas carbon dioxide). The Global Warming Essay will unravel the mystery for you.

Global warming refers to the phenomenon that the temperature of the earth's atmosphere and oceans rises over a period of time, mainly referring to the temperature rise caused by human factors. The reason is likely due to excessive greenhouse gas emissions.

Global warming is a "natural phenomenon." Various greenhouse gases such as carbon dioxide are produced when people burn fossil minerals to generate energy or cut down forests and burn them. Since these greenhouse gases are highly transparent to visible light from solar radiation, they are highly transparent to the long-wave radiation reflected from the earth. It is highly absorbent, which is often referred to as the "greenhouse effect", leading to global warming. In the past 100 years, the global average temperature has experienced two fluctuations: cold-warm-cold-warm, with an overall upward trend. After entering the 1980s, global temperatures have increased significantly. The consequences of global warming will redistribute global precipitation, melt glaciers and permafrost, and raise sea levels, which not only endangers the balance of natural ecosystems, but also threatens human food supply and living environment.

[Edit this paragraph] Background of global warming

Global warming refers to the increase in global temperature. In the past 100 years, the global average temperature has experienced two fluctuations: cold-warm-cold-warm, with an overall upward trend. After entering the 1980s, global temperatures have increased significantly.

From 1981 to 1990, the global average temperature increased by 0.48°C compared with 100 years ago. The main cause of global warming is mankind's extensive use of fossil fuels (such as coal, oil, etc.) over the past century, which has emitted large amounts of CO2 and other greenhouse gases. Because these greenhouse gases are highly permeable to visible light from solar radiation and highly absorbent to long-wave radiation reflected from the earth, this is often referred to as the "greenhouse effect", leading to global climate warming.

The consequences of global warming will redistribute global precipitation, melt glaciers and permafrost, and rise in sea levels, etc., which not only endangers the balance of natural ecosystems, but also threatens human food supply and living environment.

Global warming trends occur specifically because carbon dioxide produced when people burn fossil minerals to generate energy or cut down forests and burn them enters the Earth's atmosphere. According to climate model projections by the Intergovernmental Panel on Climate Change, global temperatures are estimated to rise by approximately 1.4-5.8 degrees Celsius (2.5-10.4 degrees Fahrenheit) by 2100. According to this prediction, global temperatures will undergo dramatic changes unprecedented in the past 10,000 years, resulting in potentially significant impacts on the global environment.

In order to stop the trend of global warming, the United Nations formulated the United Nations Framework Convention on Climate Change in 1992, which was signed and entered into force in the Brazilian city of Rio de Janeiro in the same year. Under the treaty, developed countries agreed to reduce their emissions of carbon dioxide and other "greenhouse gases" into the atmosphere by the year 2000 to 1990 levels. In addition, these countries, whose combined annual carbon dioxide emissions account for 60% of the world's total carbon dioxide emissions, have also agreed to transfer relevant technology and information to developing countries. These technologies and information transferred from developed countries to developing countries help the latter to actively respond to various challenges brought about by climate change. As of May 2004, 189 countries have officially ratified the above-mentioned convention.

[Edit this paragraph] History and prediction of global warming

Global warming is real and is ongoing!

The mainstream scientific community is unanimously aware that global warming is becoming increasingly clear. Changes to our climate are real and ongoing every day. Since the late 20th century, the average surface temperature of the Earth has increased by about 1.1F (0.6 degrees Celsius). Over the past 40 years, temperatures have risen by about 0.5f (0.2-0.3 degrees Celsius). Over the past 400-600 years, global warming in the 20th century was more than at any time in history,

10/7 of the years in the 20th century occurred in the 1990s, due to one The strongest PM since 1998 was the hottest year since reliable temperature measurements began.

Furthermore, changes in the natural environment support the fact that the Earth is warming; mountainous giaciers are also gradually receding; Arctic ice thickness has fallen by approximately 40% over the past four decades; global ocean Levels have risen about three times faster than in the past 100 years compared to the previous 3,000 years. A growing body of research shows that plants and animals are changing their ranges and behaviors in response to climate.

According to instrumental records, global land and ocean temperatures have increased by 0.75 degrees Celsius relative to the period from 1860 to 1900. Since 1979, land temperatures have risen twice as fast as ocean temperatures (land temperatures have increased by 0.25 degrees Celsius, while ocean temperatures have increased by 0.13 degrees Celsius).

According to satellite temperature detection, the temperature of the troposphere rises by 0.12 degrees Celsius to 0.22 degrees Celsius every decade. In the one or two thousand years before 1850, despite the Medieval Warm Period and the Little Ice Age, the public believed that global temperatures were relatively stable.

According to a research report from NASA's Goddard Institute for Space Studies, 2005 was the warmest year since measuring instruments were widely used in the 1800s, surpassing the record set in 1998. Hundreds of degrees Celsius. The World Meteorological Organization and the British Climate Research Unit have similar estimates, having predicted that 2005 would be the second warmest year after 1998.

It is only in recent human history that there are some temperature records. These records come from different places and vary in accuracy and reliability. Similar instrumental records of global temperature were only available in 1860, and it is believed that the records at that time were rarely affected by the urban heat island effect. Discussions and differences can be seen in temperature records over the past 1,000 years, as shown by the long-term outlook shown by multiple records within the most recent millennium. The process of climate change in the last 50 years is very clear, thanks to detailed temperature records. By 1979, humans began to use satellite temperature measurements to measure the temperature of the troposphere.

After 2000, high temperature records in various places are often broken. For example: On August 11, 2003, the Swiss town of Grono recorded a temperature of 41.5 degrees Celsius, breaking a 139-year record. In the same year, on August 10, the temperature in London, England reached 38.1 degrees Celsius, breaking the 1990 record. During the same period, the lowest temperature measured at night in southern Paris was 25.5 degrees Celsius, breaking the record since 1873. On the night of August 7, Germany also broke the record for the highest temperature in a century. In the summer of 2003, Taipei, Shanghai, Hangzhou, Wuhan, and Fuzhou all broke local high temperature records, while Zhejiang Province in China broke high temperature records more quickly, with 40 of 67 weather stations setting new records. In July 2004, Guangzhou's rare high temperature broke the 53-year record. In July 2005, two hundred cities in the United States set historic high temperature records. On August 16, 2006, the highest temperature in Chongqing was as high as 43 degrees. In Yilan, Taiwan, the temperature reached 38.8 degrees on July 8, 2006, breaking the record set in 1997. November 11, 2006 was the hottest day in Hong Kong in the entire November, with the maximum temperature reaching 29.2 degrees, which was higher than the average maximum temperature of 26.1 degrees from 1961 to 1990.

According to Xinhua News Agency, American scientists have discovered that ancient agricultural activities prevented the world from entering a new ice age. This shows that global climate warming caused by human activities may have continued for thousands of years. Researchers say prehistoric farmers who chopped down trees and cultivated the first fields changed the levels of greenhouse gases such as methane and CO2 in the atmosphere, causing global temperatures to gradually rise.

Ladiman, a professor at the University of Virginia in the United States, said: "If it were not for the greenhouse gases brought by early agriculture, the current temperature of the earth would probably still be the temperature of the Ice Age." Ladiman admitted that the research results are very likely to cause controversy. .

The National Center for Atmospheric Research said on the 17th that scientists predicted through two latest studies that even if global greenhouse gas emissions stabilize at 2000 levels, global warming and sea level rise will continue to trend this century. It is irreversible.

Scientists from the National Center for Atmospheric Research published two consecutive papers in the magazine "Science" published on the 18th, predicting the trend of global climate change from different angles. Their results will be evaluated by the United Nations' Intergovernmental Panel on Climate Change and included in the next global climate change report to be released in 2007.

In the first paper, Weigley of the National Center for Atmospheric Research proposed a simpler mathematical model for understanding global climate change. He believes that due to the "thermal inertia" of the ocean, which lags in response to external influences such as greenhouse gases, the global warming trend this century is simply a consequence of previous emissions of greenhouse gases.

According to Weigre’s prediction, by 2400, the greenhouse gas components already existing in the atmosphere will increase the global average temperature by at least 1 degree Celsius; the continuous new emissions of greenhouse gases will in turn cause the global average temperature to rise. An additional 2 to 6 degrees Celsius increase. These two factors also cause sea levels to rise by 10 centimeters and 25 centimeters per century respectively.

He said in the paper that to curb the trend of climate warming, global greenhouse gas emissions must now be controlled at extremely low levels. Even so, the trend of sea level rise may be unavoidable. Every century A rise rate of 10 centimeters is probably the most optimistic prediction.

The second paper published by Gerald Meyer and others predicts that due to the existence of "thermal inertia", even if humans do not emit any greenhouse gases into the atmosphere during this century, by 2100 The global average temperature will also rise by at least 0.5 degrees Celsius, and sea levels will rise by more than 11 centimeters. The rate of sea level rise is more than twice as high as scientists had previously predicted. Meyer explained that this is because previous predictions did not take into account the impact of melting glaciers.

Meyer's research team used two sets of mathematical models and supercomputers to simulate climate and sea level changes when global greenhouse gas emissions were low, medium and high.

[Edit this paragraph] Conditions of global warming

Earth's climate warming is related to the greenhouse effect caused by human emissions of large amounts of greenhouse gases. However, Japanese and Danish researchers recently pointed out that increases in greenhouse gases are not the only cause of climate warming, and changes in solar activity also play a role in it.

According to the "Nihon Keizai Shimbun" report, Professor Kimi Ito of the Institute of Environmental Information at Yokohama National University in Japan produced a chart. From the figure, the change curves of the earth's average temperature and the strength of the solar magnetic field over the past 200 years are basically consistent. From this, Kimiki Ito inferred that solar activity also has an impact on climate warming, and that solely using increased greenhouse gases to explain climate warming may not be comprehensive enough.

The impact of solar activity on the earth's temperature has been paid attention to by experts for a long time. Generally speaking, when there are many sunspots, solar activity is intense. For example, historical records have recorded that sunspots rarely appeared in the 17th century AD, and the earth's climate at that time was relatively cold. However, detection information obtained from the ground also shows that the change in solar radiation energy caused by changes in the intensity of solar activity is only 0.1%. Such a small change does not seem to be enough to have a big impact on the climate.

However, a hypothesis has recently emerged in the international space science community, which believes that changes in solar activity will change the cloud cover above the Earth and "amplify" the sun's impact on the Earth, thus affecting climate change. Danish scientists who put forward this hypothesis speculated that cosmic rays directed towards the earth can ionize part of the atmosphere relatively stably, making it easier for clouds to form, thus absorbing a large amount of the sun's radiation and lowering the earth's temperature. However, the high-speed stream of charged particles released during peak solar activity can interfere with cosmic rays reaching the Earth, making it difficult for clouds to form, thereby causing the Earth's temperature to rise. Currently, Danish researchers are studying various factors related to cloud formation to demonstrate the above hypothesis.

Some Japanese experts also suggested that although the change in solar radiation energy is only 0.1%, they found that this energy change can cause the earth's atmosphere to change the absorption of solar ultraviolet rays by several percent. Increased absorption will increase the temperature of the atmospheric ozone layer. Kunihiko Kodera, head of the Second Research Department of the Japan Meteorological Research Institute, said that changes in the temperature of the ozone layer will spread to the troposphere, thereby affecting the cold current and monsoon, but it is still unclear how much impact the above mechanism can have on global climate warming. In order to continue studying this topic, an international research team composed of Kunihiko Kodera and others began work last year.

[Edit this paragraph] Causes of global warming

There are many causes of global warming, which can be summarized as follows:

1. Rapid increase in population Factors

The dramatic increase in population in recent years is one of the main factors leading to global warming. At the same time, this also seriously threatens the balance of the natural ecological environment. Such a large population will emit a staggering amount of carbon dioxide every year. The result will be a direct increase in the content of carbon dioxide in the atmosphere. The carbon dioxide "greenhouse effect" formed in this way will directly affect the climate on the earth's surface. change.

2. Factors of atmospheric environmental pollution

At present, the increasingly serious environmental pollution has constituted a major global problem and is also one of the main factors leading to global warming. Now, research on global climate change has clearly shown that Earth's surface temperatures have been rising since the end of the last century.

3. Factors deteriorating the marine ecological environment

At present, sea level changes are showing a continuous upward trend. According to the predictions of relevant experts, sea levels may rise by the middle of the next century. 50cm. If appropriate measures are not taken, it will directly lead to the destruction and pollution of fresh water resources and other adverse consequences. In addition, a large amount of toxic chemical waste and solid waste generated by land-based activities are continuously discharged into the ocean; major oil spills (leakage) incidents in seawater, as well as damage to the ecological environment in coastal areas caused by human activities, etc. It is the main factor leading to the destruction of the seawater ecological environment.

4. Destructive factors such as land erosion and desertification

5. Factors of sharp decline in forest resources

Around the world, due to natural or man-made factors As a result, the forest area is shrinking significantly.

6. Hazardous factors of acid rain

The impact of acid rain on the ecological environment has attracted more and more attention around the world. Acid rain can destroy forests, acidify lakes, and endanger organisms. At present, acid rain in the world is mostly concentrated in Europe and North America. Most acid rain occurs in developed countries. In some developing countries, acid rain is also occurring and developing rapidly.

7. Factors accelerating the extinction of species

Living things on the earth are a valuable resource for mankind, and biological diversity is the basis for human survival and development. But biological species on earth are currently disappearing at an unprecedented rate.

8. Water pollution factors

According to the water quality monitoring project of the Global Environmental Monitoring System, about 10% of monitored river water in the world is polluted. Since this century, human water consumption has been increasing rapidly. The land is increasing, and the scale of water pollution is also expanding, which creates a contradiction between the supply and demand of fresh water. It can be seen that the treatment of water pollution will be very urgent and important.

9. Toxic waste pollution factors

The growing number of toxic chemicals not only poses a serious threat to human survival, but will also cause harm to the ecological environment on the earth's surface.

10 Changes in the Earth’s periodic revolution trajectory

The Earth’s periodic revolution trajectory changes from an ellipse to a circular trajectory, getting closer to the sun. According to the research of a certain scientist, the temperature of the earth has experienced alternations of high and low temperatures, and there is a certain regularity.