It is said that weather is your mood and climate is your personality. The cumulation of daily weather becomes climate as if personality reflects everyday mood over time. Weather and mood change constantly while climate and personality remain rather consistent. Many forms of lives have thrived on the Earth since the last ice age, which was followed by over 10,000 years of a warming climate. The greenhouse effect of the atmosphere surrounding the Earth is what maintains a climate suitable for humans.
Without the atmosphere, the average temperature of the Earth will drop by 33 degrees Celsius, making it inhospitable for humans. This is why the first sentence of an atmospheric and environmental sciences textbook says, “The atmosphere is an air blanket that surrounds the easily-destroyable Earth to keep delicate organisms alive.”
The air blanket that had controlled temperature is now raising the global temperature at a rapid speed due to the increased level of carbon dioxide in the atmosphere since industrialization. A relatively stable climate is now changing, which leads to more frequent extreme weather events. In less than 200 years since the Industrial Revolution, the average global temperature rose over one degree Celsius. Following the trend, the temperature will rise over two degrees Celsius before the end of the century, causing irreversible damage to the ecosystem.
The Intergovernmental Panel on Climate Change (IPCC) predicted in 2015 that a two degree Celsius rise in the average temperature will cause the extinction of 20 to 30 percent of species. In order to limit the temperature rise to two degrees Celsius, the accumulated carbon dioxide emissions since 1870 should not exceed 790 gigatons. Two-thirds of the allowed amount has already been emitted. The remaining amount of about 250 gigatons should be divided among countries that need to drastically decrease their emissions. However, such a carbon budget is likely to be run out by 2030, after which there should be no more carbon emissions. This means countries need to achieve net-zero carbon emissions by offsetting emissions with carbon reduction efforts. Over 70 countries already declared goals to achieve net-zero. Following China and Japan, South Korea also recently announced its target to achieve net-zero by 2050.
It is encouraging that many countries are joining the efforts. However, achieving net-zero emissions is not as easy as declaring it. The modern civilization, which was born as a result of the Industrial Revolution, is based on gas and coal. It will be challenging for the carbon-dependent civilization to part from carbon. Over 120 countries still haven’t announced goals to achieve net-zero emissions while the climate policies of a major emitter, such as the U.S., dramatically change due to domestic politics. A more fundamental issue is that the international norms centering around sovereign countries do not have effective tools to force countries to fulfill their carbon reduction commitments. Despite the challenges, stabilizing the atmosphere is a take of tremendous importance. “The atmosphere affects everything we see and hear. It is in an inseparable relationship with our lives. Air, which accompanies a life since its very birth, cannot be separated from us even for a moment,” the aforementioned atmospheric and environmental sciences textbook continues.