Is global warming primarily caused by human activity or are natural factors more influential?

Since James Hansen’s 1988 paper, the relationship between global warming and carbon dioxide emissions has become a major issue, leading to various international agreements and climate change measures. However, some scientists argue that natural factors have a greater impact on climate change than human activity.

 

On June 23, 1988, James Hansen of the National Aeronautics and Space Administration made a shocking announcement to the U.S. Congress. He made two shocking announcements: first, that human emissions of carbon dioxide were increasing in the atmosphere and warming the planet, and second, that if the warming continued at this rate, it would lead to extreme weather events, rising sea levels, and other global disturbances. While research on global warming had been done before, his carbon dioxide comments created a very big deal. The world then became a carbon dioxide emergency, and the Intergovernmental Panel on Climate Change (IPCC), a global research organization, was launched in November of that year and produced three reports. In 1997, the Kyoto Protocol was adopted at the United Nations Framework Convention on Climate Change in Tokyo, and countries signed agreements to reduce their carbon dioxide emissions. Now, in the 21st century, we hear about carbon dioxide and climate warming everywhere. We turn on the TV and see commercials showing bears floating on melted glaciers, and the labels of many of the products we eat and use are marked with the words “low CO2” to help mitigate climate warming. There are also campaigns to avoid pushing the close button on elevators and to wear warmer clothing indoors. Let’s take a closer look at the environmental pollution that is closest to our lives, what is climate warming, what are the solutions to combat it, and what are the problems with the ubiquitous concerns about climate warming.
There are many different types of extreme weather that the Earth experiences due to climate warming. The 1980s and 1990s were an unusually warm period for the planet, the warmest since weather records began. It was such a warm period that nine of the warmest years since weather measurements began occurred after 1990. It was also a time of many extreme weather and climate events. The worst weather events continued to occur, with unusually strong winds hitting Western Europe, devastating windstorms in many parts of Europe, and 80 tropical cyclones, hurricanes and typhoons, occurring every year in other parts of the world. Floods and droughts were also powerful, with the 1988 floods in Bangladesh inundating 80% of the country’s land mass, and the 1980s drought in Africa causing more deaths than all other disasters combined. In addition, extreme weather events such as El Niño and La Niña have been observed more frequently. As global warming continues, weather changes are occurring rapidly.
Let’s take a look at the greenhouse effect, which is the basic principle behind climate warming. The temperature of the Earth is regulated by the balance of solar radiation coming from the Sun and the Earth’s radiation going out from the Earth. These two energies are usually in equilibrium, but if this equilibrium is disrupted, the Earth’s temperature changes accordingly, bringing it back into balance. For example, if the Sun’s activity changes, causing more radiant energy to enter the Earth, the temperature will rise because more heat is entering, and if less radiant energy leaves the Earth, the temperature will rise because less heat is leaving. We won’t talk about solar radiation here, but let’s talk about global radiation. Earth’s radiant energy is absorbed by greenhouse gases such as water vapor and carbon dioxide in the atmosphere. Therefore, the more greenhouse gases there are, the less global radiant energy leaves the Earth, causing the temperature to rise. Among these greenhouse gases that human activities can affect are carbon dioxide, methane, nitrogen oxides, chlorofluorocarbons, and ozone, but the most important greenhouse gas is carbon dioxide, whose concentration continues to increase due to human activities, and its contribution to the greenhouse effect is about 70%.

 

 

At a time when the emission of carbon dioxide, which is thought to be the main cause of global warming, is increasing, what are people doing about it? First, there’s the United Nations Framework Convention on Climate Change, signed in June 1992. In this agreement, signatories agreed to short-term and long-term goals to stop climate warming: the short-term goal was to reduce emissions of carbon dioxide to 1990 levels by the year 2000, and the long-term goal was to stabilize the concentration of greenhouse gases in the atmosphere at a level that would not affect the climate. Then, in 1995, at a conference in Berlin, the parties to the agreement agreed to reduce their emissions by an average of 2008-2012, rather than the numbers set by the agreement itself. To implement these agreements, a Conference of the Parties was held in Kyoto in November 1997, and the Kyoto Protocol was adopted. Its contents include the scope of gases subject to climate warming reductions, comparisons between them, and principles for gaseous monitoring. The specifics of the Protocol were finalized at a meeting of the Conference of the Parties in Marrakech in 2001.
Apart from global agreements, there is also a movement to protect the planet’s forests. The decline of forests is also a contributing factor to increased carbon dioxide emissions, and tropical forests, which make up 47% of the planet’s total forests, are being destroyed at a rate of about 1% per year. To combat this, there is a movement to plant trees or ban deforestation. Other activities, such as reducing the sources of methane gas, are also being done to prevent the rise of greenhouse gases.
While they argue that we need to protect the planet from global warming, there are others who argue the opposite. In the 21st century, some scientists are challenging the claims of global warming, arguing that the conventional wisdom that carbon dioxide is mostly responsible for global warming is completely unfounded, and that the global carbon dioxide reduction campaigns are just a business play by governments around the world.
First, let’s look at the real background of their claimed climate warming. In the 1970s, environmental pollution became so severe that many countries passed laws and created authorities to monitor and prevent pollution. As a result of their efforts, by 1985, the air and water quality had improved noticeably. However, as a result of this improvement, environmental agencies were in danger of running out of work to do. They were faced with the dilemma of having to pollute the environment, but not being able to do so intentionally. If this situation continued, the people who worked for the EPA, as well as the companies that were involved, would go out of business. This is where James Hansen’s remarks at the U.S. Congress came in like a savior. Global warming was taken very seriously, and efforts to mitigate it were seen as very legitimate, and carbon dioxide reduction was a good goal. The environmental authorities were again able to carry the banner of global warming. As a result, about 1 trillion yen a year in Japanese taxes are spent on global warming measures, diverting money that could be spent elsewhere, and research and development expenditures related to global warming are diverting money away from other areas of research. In addition to national organizations such as environmental agencies, companies have also jumped on the bandwagon. Capitalizing on people’s desire to love the planet a little bit, they’ve turned up the heat on the environmental business, pushing out eco-friendly products.
In the face of warming claims, they ask the question: Is the climate really warming? First, if you look at the graph used by James Hansen in his testimony to Congress about the dangers of carbon dioxide, you’ll see a sharp drop in temperature around 1970. If the Earth was still warming, this drop would not have occurred. Since 1980, the following argument has been put forward: global temperatures are primarily determined by solar activity, and human activity has a very small effect on them. Even the sharp cooling of the Earth between 1940 and 1970 can be explained by changes in solar activity. According to NASA’s weather satellite NOAA, observations from around 2008 show that global temperatures have increased only slightly over the past 30 years. While some areas of the Northern Hemisphere have shown a warming trend, the entire Southern Hemisphere and Antarctica have shown no change in temperature or even a decrease. If carbon dioxide is the main driver of climate warming, then the carbon dioxide emitted by anthropogenic activities should be rising everywhere, as it is diffusing straight into the Earth’s atmosphere, so it’s normal for temperatures to rise everywhere. Therefore, the different trends in the Northern and Southern Hemispheres cannot be attributed to global warming. They also doubt that the warming is caused by human emissions of carbon dioxide. One greenhouse gas that has received less attention is water vapor. Water vapor has the strongest greenhouse effect of all greenhouse gases and is responsible for most of the global warming, more than 90%. This water vapor travels around the planet by convection, and its movement can cause dramatic temperature changes.
They dispute claims of rapid climate change and extreme weather events. First, data from NOAA, the National Oceanic and Atmospheric Administration, shows that the number of hurricanes making landfall in the United States has not increased from 1860 to 2000. In Nature, a team of Swedish researchers led by Johan Nyberg concluded that the claim that global warming is causing an increase in hurricanes is due to an underestimation of the number of hurricanes in the past. While current hurricane counts are highly accurate because they use satellite imagery, past hurricane counts are likely to be missing a large number of hurricanes. So the researchers estimated the number of hurricanes in the past using the traces of storms left behind by coral reefs on the ocean floor, and found that there has been little change in the number of hurricanes over time.
Clearly, climate is closely linked to our lives and nature. Right now, on TV, weathermen are talking about how it’s colder this year than last, and the news is reporting that seasonal changes in weather are changing the species of fish in the ocean. So if the climate is changing, we are experiencing it in our bodies, and the nature we live in is being directly affected by it. And now, after decades of experience, we have a vague sense that our planet is changing. If the first argument for global warming is correct, then we are responsible for the changes we have caused, and if the second argument is correct, then it is only an argument that the earth may not be warming, not that the earth’s environment is not being polluted, so we should not stop caring for the earth while remaining vigilant against business products that use the mantle of global warming.