Page 27 - 全球气候变化及其影响Global Climate Change and Its Impacts-185×260

Chapter 1 Scientific Basis of Global Climate Change

when decomposing in soil. Additionally, wastewater treatment processes produce N O, par-
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ticularly when treating wastewater containing high concentrations of organic matter. Specific
industrial processes, such as nitric acid production and certain chemical reactions, also emit
nitrous oxide.
Although the concentration of nitrous oxide (N O) in the atmosphere is relatively low,
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its impact on global climate warming cannot be ignored. More seriously, nitrous oxide also
causes damage to the stratospheric ozone layer. The ozone layer serves as Earth’s natural
protective barrier, effectively blocking most harmful ultraviolet radiation and protecting liv-
ing organisms from its harm. However, the presence of nitrous oxide weakens this protective
barrier, causing thinning of the ozone layer and thereby increasing the amount of ultraviolet
radiation reaching the Earth’s surface. This not only poses threats to ecosystems by affecting
plant growth and marine ecology, but also has negative impacts on human health, increasing
the risks of diseases such as skin cancer and cataracts.
Therefore, the control and mitigation of nitrous oxide (N O) emissions are particularly
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crucial. By improving agricultural production methods, optimizing wastewater treatment
technologies, and adjusting industrial production processes, we can effectively reduce N O
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emissions, thereby mitigating its impacts on global climate warming and ozone layer deple-
tion, while protecting Earth’s ecological environment and human health.
In summary, greenhouse gas emissions are one of the primary causes of the current
global warming phenomenon. The continuously increasing concentrations of greenhouse
gases such as carbon dioxide, methane, and nitrous oxide directly alter the Earth’s energy
balance, leading to a series of severe consequences including rising global average tempera-
tures, frequent extreme weather events, and sea-level rise. To effectively address climate
change, reducing greenhouse gas emissions has become an urgent task faced collectively by
the international community. Governments, businesses, and the public need to work together
through measures such as promoting clean energy, improving energy efficiency, optimizing
industrial structures, and strengthening environmental protection to achieve a low-carbon de-
velopment pathway, mitigate the pace of climate change, and adapt to the challenges posed
by unavoidable changes.

II. Land Use Changes

Activities such as deforestation, urbanization, and agricultural expansion not only di-
rectly alter surface cover but also exert multifaceted impacts on the global climate system
through complex physical, biological, and chemical processes. These activities modify sur-
face albedo, thermal capacity, water cycle, and carbon cycle, thereby generating significant
feedback effects on regional and global climate patterns.
Firstly, deforestation is one of the most representative activities in land use changes.
Forests, as Earth’s largest terrestrial ecosystem, possess criticalcarbon sink functionsand cli-
mate regulation functions. Deforestation not only directly reduces vegetation cover but also

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