By AMS President Anjuli S. Bamzai
Blossoming cherry trees are stars of springtime in Washington, D.C., and the most popular place to visit the cherry blossom trees is the Tidal Basin. Their bloom is one of the most joyful events of the year, awaited with much anticipation by tourists, meteorologists, local businesses, and the National Park Service.
Celebrating the friendship between the Japanese and American peoples, the Tidal Basin cherry trees were a gift from the Mayor of Tokyo to the United States in 1912. While the precise timing of peak bloom varies from year to year (April 4 on average, driven largely by winter/early spring temperatures), peak bloom has been occurring earlier due to warming trends. Furthermore, a combination of rising sea level and sinking land has necessitated plans for a new seawall that requires many existing trees to be removed. Yet the government of Japan has promised new trees to replace those that were lost.
This year’s beautiful blossoms strongly reminded me of the remarkable contributions of Japanese Americans — in particular Japanese American meteorologists. Our science would be especially bereft without the contributions of several scientists who, after receiving their advanced degrees at the University of Tokyo in the so-called “Syono school” of dynamic meteorology, immigrated to the U.S. from postwar Japan. Among them were Tetsuya Fujita, Akio Arakawa, Akira Kasahara, Kikuro Miyakoda, Takio Murakami, Katsuyuki Ooyama, Michio Yanai, and of course, Syukuro ‘Suki’ Manabe, one of the three recipients of the Nobel Prize in Physics in 2021.
Celebrating AAPI Heritage Month, in this post I chose to showcase the contributions of the legendary Dr. Tetsuya Theodore ‘Ted’ Fujita. Nicknamed “Mr. Tornado,” he linked tornado damage with wind speed and in 1971, developed the Fujita scale for rating tornado intensity based on ground and/or aerial damage surveys. He is also recognized as the discoverer of downbursts and microbursts, which are serious potential threats to aviation safety. Thus his discoveries made aviation safer.
But let’s take a step back. How did Fujita get interested in tornadoes in the first place? In part, his involvement was yet another legacy of the Manhattan Project: Fujita began his life’s work studying damage in Hiroshima and Nagasaki in the aftermath of the atomic bombs.
Fujita was working as assistant professor in physics at Meiji College of Technology in Tobata, exactly halfway between the two cities. A couple of years earlier, in compliance with his dying father’s wishes, he had opted to go to Tobata for his studies in mechanical engineering rather than Hiroshima. In the month following the bombings, Fujita and his team of students went on an observational mission to study the blast zones at both sites. At Nagasaki, through studying the burn marks of various objects, Fujita had the goal of estimating the position of the atomic bomb when it exploded. At ground zero, most trees, though scarred black by radiation, were still standing upright while buildings were in ruins. Seen from above, it looked like a giant starburst pattern.
After WWII ended, he joined the University of Chicago. By a stroke of genius, the Japanese American meteorologist was able to draw comparisons between severe weather and the nuclear shock waves he had studied some twenty-five years earlier at Hiroshima and Nagasaki, through studying the debris and damage of tornadoes before cleanup. He led the development of the Fujita Scale to categorize tornado intensity, a modified version of which remains in use today.
Following the Super Outbreak of 3–4 April, 1974, which covered over 2,600 miles and produced nearly 150 tornadoes in an 18-hour period, Fujita carried out aerial and ground damage surveys covering over 10,000 miles. Through meticulous analysis of the observational data, he demonstrated the existence of smaller tornadoes — suction vortices — within the parent tornado. The aerial surveys also led to the discovery of microbursts.
Photo: Dr. Fujita as a professor of Geophysical Sciences at the University of Chicago, photo taken in April 1961. Special Collections Research Center, University of Chicago Library.
You can read more about his discovery of the downburst and its contributions to aviation safety (including his work as a principal investigator for the National Intensive Meteorological Research On Downburst [NIMROD] project) here.
In 2000, two of his former students organized the “Symposium on the Mystery of Severe Storms: A Tribute to the work of T. Theodore Fujita,” held at the 80th AMS Annual meeting. They were none other than Gregory S. Forbes from The Weather Channel and Roger M. Wakimoto from UCLA, both distinguished meteorologists in their own right. Roger was of course our AMS President in 2017–2018. The photo below shows the three of them at an event at the University of Chicago from the early 1980s.
Dr. Roger Wakimoto (left), Dr. Ted Fujita (middle) and Dr. Gregory Forbes (right), taken in the early 1980s when all were at the University of Chicago. Photo Courtesy of Roger Wakimoto, honorary member of the AMS.
You can read the proceedings of the Symposium here to get a fuller sense of Fujita’s immense contributions to atmospheric science. In this short piece, I have barely scratched the surface.
You can also learn about Fujita through the PBS American Experience series, which describes events and people who have shaped the landscape over the course of history. Fujita is profiled in the episode titled, “Mr. Tornado.”
Featured image: Cherry blossoms surround the Tidal Basin in Washington, D.C. Photo: National Park Service, Kelsey Graczyk
Anjuli is grateful to Katherine ‘Katie’ Pflaumer for providing useful edits.