Emperor Naruhito, who ascends the Chrysanthemum Throne on Wednesday following the abdication of his father, Emperor Emeritus Akihito on Tuesday, is the first emperor who has studied outside Japan. He is known for his wide range of interests in foreign countries and also for his compassionate personality.

While the public might have a refined and solemn image of the emperor, he is sociable and has a good sense of humor in his writings recounting entertaining anecdotes. He is also an expert on water issues and it is expected the emperor will play somewhat of a new role as the symbol of the state while carrying out his nonpolitical duties.

The emperor has made dozens of trips and official visits to foreign countries since his first overseas trip when he visited Australia in 1974.

As the first in the direct line of succession to the Chrysanthemum Throne to study abroad, the emperor went to the United Kingdom in 1983 and spent two years living in a dormitory and studying at Oxford University's Merton College.

The emperor's memoir of his experience in Oxford, "Temuzu to Tomoni" ("With the Thames"), was released in 1993, and translated into English as "The Thames and I: A Memoir of Two Years at Oxford" in 2006. In the book, he explained that he researched the history of transportation on the River Thames because he has been interested in transportation since his childhood.

"I could take a trip to an unknown world even by just walking on a path in the Akasaka Estate, especially because I was not allowed to go outside freely," he wrote. He also noted that reading "Narrow Road to the Deep North," the 17th-century travel diary by haiku poet Matsuo Basho, deepened his interest in transportation.

In his memoir, he wrote that he wanted to research water transport in the U.K. in association with his studies on medieval water transport in the Seto Inland Sea during his time at Gakushuin University in Tokyo.

His writings detail not only his academic experience, but also his student life.

In one episode, the emperor recalled doing his own laundry for the first time.

"Following the instructions, I put the clothes into the machine, added detergent and inserted coins. Returning after about 40 minutes, I found the floor was covered with bubbles, and the bubbles were apparently flowing from my machine," he wrote. "One nearby student was looking stunned. He said: 'Is this yours? The bubbles are overflowing.'"

However embarrassing, the emperor wrote it was good he cleaned up the water and was able to become acquainted with the German student after apologizing.

In another episode, the emperor introduced conversations with his friends at the dorm. One day, his friends asked him what the Japanese word for "your highness" was.

"Then I taught them I am 'denka.' Then I foolishly point to a light in the ceiling and said it was 'denki,' not 'denka' and told them not to confuse them," he wrote. "I realized I shouldn't have said it, but it was too late. They liked to point at me and say denki and to point at the light and call it denka."

After returning to Japan in 1985, the emperor resumed his studies at Gakushuin University's graduate school in 1986 and went to Nepal the following year for his official visit where he developed interest in issues surrounding water.

The emperor wrote in his recently published book titled "Suiunshi Kara Sekai no Mizu e" ("From the history of water transport to the world's water") that he saw people carrying water on a mountain in Nepal.

"Many women and children were gathering around a tap to collect a bit of water from it. Collecting water is really hard work and I wondered how long it takes to fill their jars with water," he wrote. "This scene is what comes to mind when I consider water issues, and I think it is the starting point of my activities."

In this compilation of the emperor's speeches over the last 30 years, he shared in his introduction that his interest in water developed further since serving as honorary president of the Third World Water Forum in 2003. At the forum held in areas around Lake Biwa and the Yodo River, the emperor gave a speech on the transportation of the lake and river water in ancient and medieval times. Since then, he has made keynote speeches at four World Water Forums and sent video messages to two.

The emperor also gave lectures at the U.N.'s Special Thematic Session on Water and Disasters in New York in 2013 and 2015 and he also served as honorary president of the U. N. Secretary General's Advisory Board on Water and Sanitation from 2007 to 2015.

The emperor has given speeches, mostly based on what he learned at places he visited, according to a book titled "Shintenno to Nihonjin" ("New Emperor and Japanese") written in November by Taisei Koyama, one of his friends from Gakushuin kindergarten.

"His highness has been researching at places by making use of his invitations for official duties," Koyama wrote.

Regarding the emperor's research that he started as a history major at Gakushuin University, Koyama, who is a sociologist, wrote there were people who opposed the emperor's history research because it could lead to researching the history of the imperial family and the roots of the nation.

"It was because if he were to research the history specifically, it could lead to many inconsistencies (in the imperial history)," Koyama wrote, adding that he entered the history department of the university against such opposition.

"It seems the crown prince, as next emperor of Japan, considers presenting water issues to the world as his duty," Koyama wrote.

The emperor's consideration is expressed in his book when he insisted further efforts are required to improve the situation where many people do not have access to sanitary facilities and tackle global warming and natural disasters.

"As it is believed that water issues associated with massive tsunami and global warming are becoming more and more serious now and in the near future, intensified measures are called for. I myself will continue to have sympathy for those who are in difficult situations in Japan and the rest of the world," he wrote.

Kenzo Hiroki, professor at the National Graduate Institute for Policy Studies, who has given advice to the emperor on water issues, said the emperor's past activities on the issues would shape his role.

"He always has had an idea of trying to bond with the disadvantaged through water issues. His experiences will be of help to him after ascending the throne," Hiroki said.

Information from Kyodo added. Download the PDF of this Emperor Naruhito’s Ascension Special