4. Promises made by everyone on the earth
Fundamentally changing global warming countermeasures
As mentioned above, it was when the public was starting to become more aware of global warming that Professor Schellnhuber began his research. We did not know much at that time. While we knew that the earth was getting warmer due to carbon dioxide emissions resulting from human activities, we didn’t know yet what threats we might encounter because of it then.
Professor Schellnhuber felt the need to change the direction of discussion on global warming countermeasures. He decided to publish the results of his research for the world. He said, "We must prevent the melting of large ice sheets. If they melt, the oceans will rise by 70 meters and inundate most of the coastal areas on the earth. We must prevent this."
Restraining the increase in temperature requires us to reduce our carbon dioxide emissions. But we need to know how to cut them and how much they should be cut.
Professor Schellnhuber has promoted the Carbon Budget Approach. The Carbon Budget Approach clarifies how much carbon dioxide we must cut to achieve our goal. A global carbon budget can be calculated to meet the environmental target of the Paris Agreement - keeping global average temperature increase well below 2 degrees C. This has become the fundamental concept in consideration of global warming countermeasures.
The cooperation of influential people around the world
It was essential to have the participation of influential people around the world to change the direction of the discussion.
For example, 2 degrees C target was first discussed at the United Nations Framework Convention on Climate Change (UNFCCC) Conferences of the Parties (COP) 1 held in Berlin, Germany in 1995. The conference was held soon after the establishment of the PIK. Professor Schellnhuber participated in the conference with the German Minister of the Environment, who was the chair of the conference.
Professor Schellnhuber had discussed the 2-degree C target with the minister. The minister was a female physicist who understood and agreed with Schellnhuber.
That minister was Angela Merkel, who would go on to become the Prime Minister of Germany and take the initiative in bringing the discussion of global warming countermeasures to the international level. Professor Schellnhuber has built a trusting relationship with Merkel over the 20 years since then and has supported her as a science advisor.
In 2015, Pope Francis presented the Laudato Si, the first encyclical letter (the official letter from the Pope) in history to address environmental issues. In this letter, Pope Francis mentioned global warming. Professor Schellnhuber contributed to the creation of this letter as a scientist. Immediately before COP21, at which the Paris Agreement was agreed, this message from the supreme authority of the Catholic Church had a significant influence on people.
Professor Schellnhuber thought it was lucky for him to be able to discuss his ideas with these influential people.
The Paris Agreement, and...
His studies and approaches changed the public's awareness of global warming countermeasures over 20 years. And finally, the Paris Agreement was presented at COP21 in 2015. Member countries promised to achieve the 2-degree C target together.
However, this is not the end. We just reached the starting point in addressing various environmental issues.
Carbon dioxide emissions have been increasing. Although the target is 2 degrees C, the average temperature has already increased by 1 degree C compared with that before the industrial revolution. During the past 20 years, the environment has significantly deteriorated. If we continue discharging carbon dioxide at the current level, the temperature will continue to rise.
According to the calculation, it would be difficult to meet the 2-degree target without decreasing carbon dioxide emissions by 2020 and achieving zero emissions by the latter half of the 21st century.
What should we do to prevent this? The remaining global carbon budget is about 600 billion tons. Professor Schellnhuber pointed out that we need to use this wisely. We need to fundamentally shift our social structure away from dependence on fossil fuel to something else in order to reduce carbon dioxide emissions to within the acceptable range.
He says that this all depends on individual decisions. People need to try hard to do things that restrain carbon dioxide emissions in their day-to-day lives. For example, when we go shopping, we should choose products whose manufacture reduces carbon dioxide emissions. Manufacturers also need to change their systems.
It is also important to support leaders who are actively working on global warming countermeasures. Professor Schellnhuber suggests that everyone think about this during elections. He is dreaming about a world in which individuals make proper decisions regarding carbon dioxide emissions and in which individual movement will lead to social activity.
Mission as a scientist
As is stated above, Professor Schellnhuber has not only carried out research as a scientist, but has also tried hard to provide his results to the world. He has worked in cooperation with influential people and has contributed through political activity as well.
While he realizes some disagree with the idea that a scientist should be involved in such activities, he believes it is important. During World War II, scientists took the attitude that they were not responsible for how the results of their research were used. They did not take responsibility even if their research was used to create weapons of mass destruction.
Professor Schellnhuber believes that such attitude is far from correct and is a sin. Scientists know the meaning of their research more than anyone else, so they cannot be free from responsibility for its impact on society. He believes that it is the mission of scientists to become politically involved when necessary to help the world understand the dangers of misuse as Einstein did after World War II.
Professor Schellnhuber is sometimes stressed out, but his 9-year-old son always cheers him up. This little boy encourages him to move forward to solve problems for the future.
Professor Schellnhuber thinks his generation received a lot of benefits and opportunities, and that they also need to ensure that the next generation has the same benefits and opportunities. This does not necessarily mean improving the situation. It means not allowing it to worsen. While understanding that this is quite difficult, he believes that he has the obligation to try his best.