In this blog post, we’ll explore the causes and consequences of global warming, as well as the international community’s response and various measures to address it.
Causes of Global Warming
“Climate” refers to the average state of atmospheric phenomena observed in a specific region over a long period of time. However, in recent years, the characteristics of the seasons have been changing compared to the past. Spring and fall are gradually becoming shorter, while summers have become longer and hotter; in winter, relatively warm weather often persists before being followed by sudden cold snaps. These changes are being observed not only in South Korea but worldwide, indicating that the climate is undergoing long-term shifts.
Global warming refers to the phenomenon of the Earth’s average temperature rising continuously, and it is accompanied by various phenomena such as changes in terrestrial and marine ecosystems, rising sea levels, and an increase in extreme weather events. While the Earth’s climate has undergone natural changes in the past, the global warming currently under discussion primarily refers to the rapid climate change driven by human activities since the Industrial Revolution. Since the Industrial Revolution, the use of fossil fuels has increased dramatically, and as industrialization and urbanization have progressed, forests have been destroyed; these changes have resulted in a significant increase in the concentration of greenhouse gases in the atmosphere. Therefore, global warming is understood as a phenomenon closely linked to human activities since the Industrial Revolution.
The causes of global warming can be divided into natural and anthropogenic factors, but the most significant cause today is the increase in greenhouse gases resulting from human activities. Greenhouse gases are gases that cause the greenhouse effect, which is the phenomenon whereby the atmosphere absorbs a portion of the energy received from the sun and re-emitted from the Earth’s surface as radiant energy, thereby maintaining the Earth’s average temperature. Although the greenhouse effect is often perceived solely in a negative light, without greenhouse gases, the Earth would be unable to maintain its current average temperature; theoretically, it is estimated that the average temperature would drop to approximately -18°C. Therefore, the greenhouse effect itself is a natural phenomenon essential for the survival of living organisms; the problem lies in the fact that human activities are excessively amplifying this effect.
Greenhouse gases include carbon dioxide, methane, nitrous oxide, and water vapor, and various synthetic compounds have been added due to industrial and technological advancements. The international community has signed several agreements to manage these greenhouse gases. Currently, efforts to reduce greenhouse gas emissions are centered on the Kyoto Protocol and the Paris Agreement, and the gases targeted for reduction include carbon dioxide (CO₂), methane (CH₄), nitrous oxide (N₂O), hydrofluorocarbons (HFCs), perfluorocarbons (PFCs), sulfur hexafluoride (SF₆), and nitrogen trifluoride (NF₃).
Each greenhouse gas has a different impact on global warming. To compare these effects, the Intergovernmental Panel on Climate Change (IPCC) uses the Global Warming Potential (GWP). When carbon dioxide is set as the baseline value of 1, methane is estimated to have a warming effect approximately 27 to 30 times greater, and nitrous oxide approximately 273 times greater. Some fluorinated greenhouse gases exhibit a warming potential far higher than this.
The Earth’s atmosphere consists mostly of nitrogen and oxygen, with carbon dioxide accounting for only a very small proportion. However, since the Industrial Revolution, the use of fossil fuels has increased rapidly, causing atmospheric carbon dioxide concentrations to rise continuously. Furthermore, the expansion of agriculture and livestock farming has increased emissions of methane and nitrous oxide, while the use of fluorinated greenhouse gases has also expanded in sectors such as refrigerants and the semiconductor industry. This increase in anthropogenic greenhouse gases is considered the primary cause of the rise in global average temperatures.
Changes Brought About by Global Warming
Global warming is already causing distinct changes in various fields. In South Korea as well, rising average temperatures are causing plants to bloom earlier, and several studies have shown that the optimal timing for tree planting and agricultural activities is also occurring earlier than in the past. Changes in the timing of soil thawing and plant growth are also affecting agricultural and forest management practices.
The distribution of insects is also changing significantly. Mosquitoes, which used to be seen mainly in the summer, are now commonly active from late spring through fall and even into early winter. Dragonflies are also active for longer periods, and species that previously inhabited mainly southern regions are now being found in central and northern regions as well. These changes demonstrate that, as temperatures rise, the habitats of living organisms are gradually shifting northward.
The marine environment is also changing rapidly. Water temperatures in the waters surrounding South Korea are steadily rising, and as a result, the distribution of fish species is shifting. Cold-water fish species are gradually moving northward, while warm-water species are expanding their range northward. These changes are affecting not only fisheries but also the marine ecosystem as a whole.
Changes in the Arctic region are another significant example. Arctic sea ice is steadily decreasing, and as a result, the potential for utilizing the Arctic shipping route is gradually increasing. However, the timing of the Arctic shipping route’s commercialization and its economic viability may vary depending on future climate change, international political conditions, and technological advancements, making it difficult to predict with certainty.
International Efforts to Address Global Warming
Reducing greenhouse gas emissions is of paramount importance in addressing global warming. To this end, the international community is responding collectively through various agreements and systems.
A key starting point is the “United Nations Framework Convention on Climate Change (UNFCCC),” adopted in Rio de Janeiro, Brazil, in 1992. This convention aims to prevent dangerous climate change resulting from human activities by maintaining greenhouse gas concentrations at a stable level. Signatory nations are required to survey and regularly report their greenhouse gas emissions and removals, and to establish national policies and plans to address climate change. It also includes provisions regarding technological cooperation and financial support between developed and developing countries.
Subsequently, the “Kyoto Protocol,” adopted in Kyoto, Japan, in 1997, was the first international agreement to impose legally binding greenhouse gas reduction targets on developed countries. The gases subject to reduction included carbon dioxide (CO₂), methane (CH₄), nitrous oxide (N₂O), perfluorocarbons (PFCs), hydrofluorocarbons (HFCs), and sulfur hexafluoride (SF₆). However, the agreement faced limitations, as some countries did not participate or later withdrew, and it drew criticism from the international community because mandatory reduction targets did not apply to developing countries.
To address these limitations, the “Paris Agreement,” adopted in 2015, has become the cornerstone of current international climate policy. The Paris Agreement stipulates that all parties—including both developed and developing countries—must voluntarily establish Nationally Determined Contributions (NDCs) and continuously strengthen them. It also sets a shared goal of keeping the rise in global average temperature well below 2°C above pre-industrial levels and, if possible, limiting it to 1.5°C. South Korea, too, has established and is pursuing carbon neutrality and greenhouse gas reduction targets in accordance with the Paris Agreement.
Alongside international agreements, countries are strengthening their responses to climate change by implementing various policies, such as expanding renewable energy, improving energy efficiency, fostering eco-friendly industries, and establishing carbon emissions trading systems.
Various Technologies for Reducing Greenhouse Gases
To mitigate global warming, it is important not only to establish international frameworks but also to develop technologies that reduce greenhouse gas emissions in industrial settings.
One representative example is carbon emission reduction technology in the steel industry. In conventional steelmaking processes, coke—which consists primarily of carbon—is used to remove oxygen from iron ore, a process that generates large amounts of carbon dioxide. Recently, hydrogen-based ironmaking technology—which uses hydrogen instead of coke—has been developed. When hydrogen is used as a reducing agent, water is produced as a byproduct, significantly reducing carbon dioxide emissions. Steel companies around the world are pushing for the commercialization of this technology, which is regarded as one of the key technologies for achieving carbon neutrality.
Meanwhile, shale gas is natural gas found in shale formations. Since the 2000s, production has expanded as its economic viability has greatly improved due to advancements in horizontal drilling and hydraulic fracturing technologies. Because shale gas emits relatively less carbon dioxide during combustion than coal, it is being utilized in the energy transition process in some countries. However, natural gas is also a fossil fuel; methane can leak during production and transportation, and the environmental impact of hydraulic fracturing technology remains a subject of ongoing debate. Consequently, renewable energy, hydrogen energy, and carbon capture, utilization, and storage (CCUS) technologies—rather than shale gas itself—have recently been gaining attention as the core elements of long-term carbon neutrality strategies.
Conclusion
We have examined the causes and consequences of global warming, as well as the various international efforts and technological responses aimed at addressing it. Global warming is not a problem for any single country alone, but a shared challenge that the entire planet must address together. The impacts of climate change can be mitigated not only through cooperation among nations and the sustained efforts of the international community, but also when both businesses and individuals join in practical efforts to reduce greenhouse gas emissions. For a sustainable future, it is paramount that the entire world takes responsibility and actively participates in addressing climate change.
