In this blog post, we’ll take a detailed look at the causes and effects of global warming, the international community’s response, and various perspectives on the issue, incorporating the latest information.
What is global warming?
The Earth is surrounded by an atmosphere formed by gravity. One of the atmosphere’s primary roles is to partially prevent thermal energy from the Sun from escaping directly into space, thereby maintaining an appropriate temperature at the Earth’s surface. Without this natural greenhouse effect, the Earth would have become an environment where life as we know it could hardly survive. In fact, while the Moon—which has virtually no atmosphere—experiences extreme temperature fluctuations between day and night, the Earth maintains relatively stable temperatures thanks to the greenhouse effect, allowing diverse life forms to thrive.
The gases in Earth’s atmosphere that play this role are called greenhouse gases. Global warming refers to the phenomenon in which the concentration of greenhouse gases increases due to human activities, intensifying the greenhouse effect and resulting in a long-term rise in Earth’s average temperature. This can be understood as similar to the principle by which heat is trapped inside a plastic greenhouse, causing the internal temperature to rise.
The primary gases responsible for the greenhouse effect include carbon dioxide, methane, nitrous oxide, and water vapor. Among these, carbon dioxide currently has the greatest impact on global warming. Although methane has a much stronger greenhouse effect than carbon dioxide on a per-unit basis, carbon dioxide is considered the greenhouse gas with the greatest impact on global warming because the total amount of carbon dioxide emitted into the atmosphere is overwhelmingly larger.
Since the Industrial Revolution, energy demand has continued to rise due to rapid industrialization and population growth. To meet this demand, the use of fossil fuels such as coal, oil, and natural gas has increased significantly, resulting in the emission of massive amounts of carbon dioxide into the atmosphere. Virtually all activities that sustain modern civilization—including various modes of transportation such as cars, airplanes, and ships, as well as coal-fired power plants that generate electricity, industrial facilities, and heating and cooling systems in buildings—are directly or indirectly linked to carbon dioxide emissions.
Although the adoption of renewable energy is expanding rapidly and the use of electric vehicles is increasing today, fossil fuels still account for a high proportion of global energy consumption. Furthermore, as the global population grows and economies develop, energy demand is steadily increasing; unless sufficient greenhouse gas reduction policies are implemented, carbon dioxide emissions are likely to remain at high levels for a considerable period. In particular, industrial activity and urbanization in countries experiencing rapid economic growth are also major factors driving the increase in global energy consumption. Therefore, to mitigate global warming, it is of utmost importance to reduce dependence on fossil fuels and continuously pursue the transition to a low-carbon energy system.
Changes Brought About by Global Warming and the International Community’s Response
Due to the effects of global warming, the Earth’s average temperature has been steadily rising compared to pre-industrial levels. According to the latest assessment by the Intergovernmental Panel on Climate Change (IPCC), the Earth’s average temperature has risen by approximately 1.1–1.3°C compared to pre-industrial levels, and the past few decades have been recorded as the hottest period in observed history. Furthermore, the recent rate of temperature rise is accelerating compared to the past, leading to growing concern within the international community regarding climate change.
Changes caused by global warming are being observed all over the world. One of the most notable examples is the retreat of the permanent snowfields on Kilimanjaro. Over the past century, the glaciers at the summit of Kilimanjaro have shrunk significantly, a phenomenon known to be common among mountain glaciers worldwide. Glaciers in the Arctic and Antarctic are also showing a continuous trend of decline, and these changes are contributing to rising sea levels. Rising sea levels are increasing the risk of flooding in coastal areas, and the long-term survival of some low-lying and island regions is under threat.
South Korea is also directly experiencing the effects of climate change. As average temperatures continue to rise, climatic patterns are shifting, and in some regions, characteristics of a subtropical climate are becoming increasingly pronounced. Consequently, ecosystems are changing, and there are reports that extreme weather events—such as torrential rains, heat waves, droughts, and cold snaps—are occurring more frequently and with greater intensity. Furthermore, it is suggested that tropical cyclones, including typhoons, may see increased precipitation and intensity due to climate change, and various extreme weather events—such as hurricanes, torrential rains, and wildfires—are on the rise in many regions around the world. Many climate scientists analyze that these changes are closely linked to climate change caused by human activities.
Since the Earth’s atmosphere circulates continuously across national borders, global warming is not a problem that can be solved by the efforts of any single country. Therefore, a collective response from the international community is essential. In particular, since tropical rainforests play a crucial role in absorbing carbon dioxide from the atmosphere, international efforts to protect large-scale forests, such as the Amazon, are ongoing.
The international community has established various agreements and systems to address climate change. The “United Nations Framework Convention on Climate Change” was adopted in 1992, and subsequently, the “Kyoto Protocol” in 1997 set greenhouse gas reduction targets for some developed countries. Subsequently, to encourage broader participation, the international community adopted the “Paris Agreement” in 2015. Currently, most countries have established voluntary Nationally Determined Contributions (NDCs) and are implementing policies to reduce greenhouse gas emissions. The Paris Agreement aims to keep the rise in global average temperature well below 2°C above pre-industrial levels and, if possible, to limit it to 1.5°C.
However, the growing demand for energy driven by global population growth and economic development remains a major challenge. Many countries still find it difficult to rapidly reduce their dependence on fossil fuels, and significant amounts of greenhouse gases continue to be emitted across various sectors, including industry, transportation, and power generation. For these reasons, the international community is pursuing climate change mitigation by simultaneously implementing various measures, such as expanding renewable energy, improving energy efficiency, utilizing carbon capture and storage (CCS) technology, and transitioning to eco-friendly industries.
Solutions and Diverse Perspectives on Global Warming
To mitigate global warming, it is crucial to reduce the use of fossil fuels—which emit large amounts of greenhouse gases—and expand the use of low-carbon energy sources that can replace them. These energy sources are generally referred to as alternative or clean energy, and currently, solar, wind, hydro, geothermal, ocean, and bioenergy are utilized as representative forms of renewable energy. Furthermore, because nuclear power emits very little carbon dioxide during the power generation process, it is utilized as a major power source for achieving carbon neutrality in some countries, although its role and share vary depending on each country’s energy policy.
In the past, tar sands and oil shale were also mentioned as forms of alternative energy; however, as they are types of fossil fuels that produce high levels of greenhouse gas emissions, they are no longer classified as eco-friendly alternative energy sources for addressing climate change. Furthermore, while biofuels are being utilized as alternatives to petroleum, various factors—including production costs, raw material availability, and environmental impact—must be considered together.
Since each energy source has both advantages and disadvantages, countries are implementing various energy policies by taking into account their own industrial structures, energy resources, geographic environments, and economic conditions. Recently, as the efficiency of solar and wind power generation has greatly improved and the cost per unit of electricity has continued to decline, their adoption is rapidly expanding worldwide. Furthermore, with the concurrent development of technologies such as energy storage systems (ESS), smart grids, and hydrogen energy, the establishment of a low-carbon energy system is proceeding at an even faster pace.
South Korea, too, is pursuing a range of policies aimed at achieving carbon neutrality, including expanding renewable energy, improving energy efficiency, fostering a hydrogen economy, utilizing nuclear power, and reducing carbon emissions in the industrial sector. Given that South Korea has a high population density relative to its land area and a high demand for industrial electricity, ensuring a stable power supply is also considered a critical challenge. Consequently, how to harmoniously utilize nuclear power and renewable energy remains a subject of ongoing policy debate.
Meanwhile, there are diverse perspectives on global warming. Some argue that the Earth’s climate has naturally fluctuated over long periods of time and that natural variations may also play a role in current climate change. Indeed, throughout its long geological history, the Earth has cycled through ice ages and interglacial periods, and such natural climate fluctuations are well established scientifically.
However, the prevailing view in the climate science community is that current climate change cannot be explained solely by past natural climate fluctuations. In particular, the sharp increase in atmospheric carbon dioxide concentrations since the Industrial Revolution is consistent with observational data showing a rise in global average temperatures, ocean warming, glacial retreat, and sea-level rise; greenhouse gas emissions from human activities are identified as the primary cause of these phenomena.
In the past, the so-called “Climategate” controversy raised doubts about the credibility of climate change research. However, subsequent independent investigations by various countries found no conclusive evidence of research misconduct, and the scientific conclusion that human activities are the primary cause of current climate change has been upheld. Today, most major global scientific institutions and international organizations agree that human greenhouse gas emissions are the most significant cause of recent global warming.
Climate change is no longer an issue confined to specific countries but has become a shared challenge that the entire world must address together. Energy transition, greenhouse gas reduction, forest conservation, technological innovation, and international cooperation are all crucial means of mitigating global warming. At the same time, since it is difficult to completely prevent the effects of climate change, policies and social preparations to adapt to the changes already underway must also be implemented. By continuing to accumulate scientific research on climate change and fostering international cooperation based on this research, we will be able to build a more sustainable future.
