Introduction
Climate Change is not a new issue, but has been discussed for years. Researchers point out that climate change will bring incalculable loss to human society, and this problem has been widely recognized by countries in the world, becoming a global environmental concern. In order to analyze the mechanism of climate change, the concept of carbon cycle is important to be mentioned. With the entire ecological system, all the matters on the earth are in an orderly cycle. Carbon is like water, which stays in its own cycle through atmosphere, hydrosphere, biosphere and lithosphere. By examining the trace of carbon we can identify the clues of climate change.
The Carbon Cycle
The basic process of carbon cycle in nature begins with the atmospheric carbon dioxide that absorbed by plants in land and sea, and then carbon element is returned to atmosphere through biological or geological processes. Specifically, plants on the earth obtain carbon dioxide from the air, transforming it into glucose through photosynthesis mechanism. And then carbon dioxide becomes a carbon compound in plants. After passing through the food chain, it becomes the carbon compounds in animals’ bodies. The respiration of plants and animals can transform some of the carbon element from the body into carbon dioxide and release it into the atmosphere, and the other part will become a biological organism or be stored in the body. After the death of the animals and plants, the carbon in the residue also becomes carbon dioxide and eventually gets into the atmosphere through the decomposition of microbes. The animal and plant residues are buried by the sediments before they are decomposed and become organic sediments. These sediments are transformed into fossil fuels, coal, oil and natural gas due to the long term conditions of heat and pressure. When they are burned in the process of weathering or consumed by human society as fuel, carbon dioxide is oxidized into the atmosphere.
Although carbon cycle has great influence on the earth's environment, slow change of carbon geochemistry cycle is the most important controlling factor of the earth's environment. On this basis, to learn about the changes from carbon transmission process has significant meaning.
The Changes Happening
In general, a timeline of the changes in the earth’s atmosphere can be identified. The first two stages of climate change happened naturally due to the earth’s growing. Without any influences made by external factors, the carbon cycle itself changes naturally and gradually along with the aging of the planet. When the photosynthesis of plants appeared on earth around the period of the Carboniferous, lignin began to make forest rapid expand, but when there were no evolved species that had the ability to decompose lignin. As a result, a large amount of carbon dioxide was fixed into the activities of organic carbon in the biosphere, and due to the lack of decomposition, most of them converted into fossil organic carbon in the lithosphere (Loustau, 2010). This was an important stage for the planet, with the formation of a great number of coal resources in this period.
Then, at the end of the Permian, the continental orogeny occurred, and the long-term weathering of rock's ability to absorb carbon dioxide decreased. Under this circumstance, the amount of atmospheric greenhouse gases increased in a serious degree, resulting in extremely intensive greenhouse effect. This was a significant climate change due to the functions of natural system, which led to a sharp rise in temperature and severe acidification of global ocean (Myers, 2016).
As time passing by, human being stepped on the stage, and the establishment of human society’s civilization and industrialization brought the third major period of climate change. From the perspective of carbon cycle, the major changes caused by human society’s activities can be concluded from several aspects. First of all, human burns fossil fuels to generate power, artificially releasing large amounts of organic carbon and inorganic carbon from the lithosphere into the atmosphere. The exploration and burning of fossil fuels increased the concentration of carbon dioxide in the atmosphere. Carbon dioxide, as a greenhouse gas, has the function of heat absorption and heat insulation. The result of its increase in the atmosphere is the formation of an invisible glass cover, so that the heat from the solar radiation to the earth can not diverge from outer space. Therefore, the earth's surface becomes hotter and aggravates the greenhouse effect. The greenhouse effect as the major issue of our contemporary environment, is the result of excessive use of fossil fuels, followed by global warming, melting glaciers, rising sea levels, some species extinction and destruction of the food chain.
Secondly, due to the large number of fossil fuels used by human, the sulfur oxides or nitrogen oxides produced after combustion are complex chemical reactions in the atmosphere, forming sulfuric acid or nitric acid aerosols, or capturing and absorbing clouds, rain, snow and fog, and falling to the ground to become acid rain. Acid rain can lead to soil acidification. Soil contains a large amount of aluminum hydroxide. After acidification, soil can accelerate the weathering of primary and secondary minerals containing aluminum in the soil, and release a large amount of aluminum ions, forming a plant absorbable form of aluminum compounds. Acid rain can also accelerate the loss of mineral nutrients in the soil, changing the soil structure and leading to soil impoverishment, and even affecting the normal development of plants. Acid rain can also induce plant diseases and insect pests, and make crops yield substantially reduced. A long period of acid rain can cause a large amount of nutrient elements in the soil to be lost, bringing serious deficiency of the nutrient elements in the soil, thus making the soil poor (Hurtley, 2010). At the same time, acid rain can make materials in buildings like concrete, mortar and brick hardened cement dissolution, emergence of voids and cracks, leading to reduction the strength of buildings and damage the walls.
Based on the discussion above, climate change is caused by both natural system’s functions and human society’s activities. The consequence of climate change is severe, which is leading to a great damage to environment. The changing climate endangers the ecological balance, further bringing severe challenges to human life. The earth's temperature changes are recorded in detail according to the investigation reports made by Intergovernmental Panel on Climate Change (IPCC). From 1880 to 2012, the global average surface temperature increased 0.85 centigrade. Ice and snow had seen significant reduction as well. Between 2002 and 2011, the ice reserves of the Greenland ice cover reduced by about 2150 million tons each year, and the Antarctic ice cover decreased by about 1470 billion tons each year. In the past years from 1971 to 2009, the global mountain glaciers had reduced about 2260 million tons of ice each year on average. In addition, the temperature of permafrost in most areas has risen since 1980. At the same time, climate change is proved to cause rising sea level. In the last few years, the melting of ice and snow and the storage of land water were observed by IPCC. The rise of sea level has accelerated in the near future (O’Neill, Oppenheimer, Warren, Hallegatte, Kopp and Portner, 2017).
Some Solutions of Climate Change
Considering the negative effects of climate change, it is important to find ways to reduce further damages caused by greenhouse effect, acid rain, burning fossil fuels and other related problems. The most fundamental solution is to reduce the usage of fossil fuels, so that the emission of carbon dioxide and other greenhouse gases can be reduced. Most recently, researches have been carried out to explore more usage of renewable resources. For example, some renewable non fossil energies like wind, solar, hydroenergy, geothermal energy, and marine energy are all environmental friendly. Renewable natural resources can continue to be regenerated at the present stage of natural conditions, maintaining or expanding their reserves by provenance. If these resources are widely used to take place of fossil fuels, the emissions produced by fossil fuels will be greatly cut down, which is efficient to prevent the formation of acid rain and greenhouse effect.
At the same time, the control of climate change and its related problems relies heavily on the regulation of governments. On the one hand, government has its responsibilities to monitor and control climate change. In practice, governors can set up corresponding laws and legislation systems about environmental protection, reducing the damages caused by artificial attempts. On the other hand, government can support the public to reduce usage of fossil fuels and take more measures to prevent climate change. For instance, the reduction of taxes and more subsidies in the field of renewable resources are both effective.
Conclusion
On top of the discussion above, climate change is a gradual happening process that contains a series of environmental issues. From the concept of carbon cycle, the natural movement and development of ecological system and human society’s establishment are the two causes of climate change, and the changes bring severe damages to the environment. In general, the major consequences include greenhouse effect, acid rain and other following problems. In order to reduce the damages caused by climate change, replacing the fossil fuels by renewable energies. Overall, efforts should be made by every aspect of the society, including government and the public.
References
Myers T. S. (2016). Palaeoclimate: CO2 and Late Palaeozoic Glaciation. Nature Geoscience.
Hurtley, S. (2010). Carbon cycle and climate change. Science, 329.
Loustau, D. (2010). Forests, carbon cycle and climate change. Forests Carbon Cycle & Climate Change.
O'Neill, B. C., Oppenheimer, M., Warren, R., Hallegatte, S., Kopp, R. E., & Pörtner, H. O., et al. (2017). Ipcc reasons for concern regarding climate change risks. Nature Climate Change, 7(1), 28-37.