- Q: Could you explain your current research topic in an easy-to-understand way?
↓
-
I am working to elucidate the current mechanisms of change in Arctic sea ice extent and the interactions between the atmosphere, sea ice, and ocean associated with ocean changes. It is often thought that the Arctic sea ice extent continues to decline, but the summer sea ice extent stopped decreasing after a major drop in 2007 and now shows a four-year cycle of variation. The atmosphere and ocean are also exhibiting new variations, and it can be said that we have transitioned to a new climate regime where the laws and mechanisms shown in previous research no longer apply.
At first glance, changes in the Arctic Ocean may seem unrelated to us, but in years with little sea ice, early winter in Japan becomes colder, and changes in Arctic sea ice are attracting attention as a factor that influences climate change on a Northern Hemisphere scale. We are conducting research into what is currently happening in the Arctic Ocean, focusing not only on sea ice but also on the atmosphere and ocean, and using data from observation vessels and satellite observation data covering a wide area based on geophysical fluid dynamics.
The easiest way to imagine the cause of sea ice decline is that it has melted due to rising temperatures, but that alone would not have caused the drastic decline seen in 2007, nor could it explain the current four-year cycle. Of course, rising temperatures have an effect, but the reality is more complicated than that. Sea ice extent is determined by the amount of ice that is created and melted, and the amount released into the Atlantic Ocean. These are expected to be determined within an extremely complex feedback system between the atmosphere, sea ice, and ocean. Ultimately, I would like to unravel the mechanism behind current fluctuations in Arctic sea ice extent.
- Q: What motivated you to start your research?
↓
- I was originally interested in natural sciences, but what prompted me to start research was a class on physical oceanography taught by my current supervisor. I became interested in explaining the ocean through physics, and I also had more opportunities to go out into the field and do practical training. I found it fascinating that the ocean could be explained based on theory, so I joined a lab.
- Q: What are the challenges and attractions of your research?
↓
-
Only a small percentage of research goes well, and most things don't. There are times when I feel like giving up, but when I discover something new and realize, "I got it!", I feel a great sense of accomplishment. Also, when I am able to explain a complex natural phenomenon using the theory of geophysical fluid dynamics, I am amazed at how fascinating natural science (physics) is.
- Q: Tell us about the future of this research.
: Short-term (1-2 years from now) and long-term (up to 10 years from now)
↓
-
In the short term, we believe we will be able to clarify changes in the balance of momentum exchange between the atmosphere, sea ice, and ocean due to changes in sea ice type, as well as the response of ocean circulation to sea ice reduction and changes in sea ice movement.
In the long term, we would like to clarify the mechanism behind the four-year cycle of sea ice extent variation and use this information to make predictions.
The Arctic Ocean climate regime changed significantly around 2007 and 2008. Prior to that, it was generally believed that sea ice movement and area could be explained by atmospheric oscillations, but this law no longer applies. The current mechanism for sea ice extent change is extremely complex, and we must comprehensively understand the variations in the atmosphere, sea ice, and ocean. Furthermore, because it has only been 20 years since the regime change, we must find new laws from limited data. - Q: Which SDGs can your research contribute to?
↓
- This research contributes to "Goal 13: Take urgent action to combat climate change." While recent summers have been record-breakingly hot, cold events have also been observed, such as the first snowfall recorded in November in Tokyo since meteorological observations began in 11 (Meiji 8), in 2016, and a severe cold wave expected in 2024. The Arctic is the region experiencing the most rapid temperature rises in the world, and both of these events may be influenced by the decline in sea ice. Decreasing sea ice increases ocean and atmospheric temperatures, changing atmospheric patterns in the upper atmosphere. Atmospheric changes propagate far and wide, affecting Japan as well. Understanding the underlying factors behind changes in sea ice extent will not only help us assess and predict global impacts, but also contribute to our understanding of Japan's climate.
- Q: Were there any people or events that influenced you when you decided to enroll at Tokyo University of Marine Science and Technology?
↓
- I think the biggest factor was that I spent a lot of time playing in the ocean, rivers, rice fields, and mountains when I was little. Before entering university, I thought about what I was most excited about, and I decided on natural sciences.
- Q: What are your priorities and policies when conducting research?
↓
- I value my love of nature and the ocean, as well as my curiosity to learn things that no one else knows. Because I deal with natural science, I am driven more than anything by the sense that the Earth and nature are mysterious and fascinating. I also value a foundation in geophysical fluid dynamics, and place importance on how to explain complex phenomena in a simple way.
- Q: What are the positive aspects of choosing Tokyo University of Marine Science and Technology?
↓
- The best thing about undergraduate courses is that they allow students to learn by going out into the ocean. While it's possible to handle data without going out into the field, I learned the importance of going out into the field and seeing the ocean for myself. In fact, I first became aware of the appeal of oceanography during a practical observation across the Kuroshio Current during my third year of undergraduate studies.
- Q: Why did you decide to go to graduate school?
↓
-
There are still many things that we don't understand, and many things that no one knows. I would like to expand on the research I did as an undergraduate and work to shed light on changes in the Arctic Ocean.
By going on to graduate school, I was able to understand a lot more than I did in undergraduate school, my knowledge increased, and the scope of my research broadened. I think I also became more able to think about how to approach things in order to find out what I want to know. - Q: Please tell us about your dreams, goals, and the career you are aiming for in the future.
↓
- I aim to become a person who can approach climate change, which has an impact on our lives and society. Currently, I would like to remain in academia.
- Q: Please give a message to those who are currently considering going on to a master's or doctoral program.
↓
- I'm sure there will be some anxieties and obstacles, but I hope you will be honest about your curiosity and desire to learn and move forward.
