Katsuko Saruhashi was born on 22 March, 1920 in Tokyo. Her given name, Katsuko, literally translates to being strong-minded or victorious. She went on to graduate from the Imperial Women's College of Science in 1943 and joined the Meteorological Research Institute and worked in its Geochemical Laboratory. Today, on her 98th birthday, Google commemorated her with a Doodle.
Katsuko Saruhashi made some of the first measurements of carbon dioxide (CO2) levels in seawater. A pioneer in her field, Dr Saruhashi was also the first to measure radioactive material in seawater. This was one of the scientific reasons for not conducting nuclear bomb experiments in the Pacific Ocean.
Katsuko Saruhashi made some ground-breaking discoveries as a geochemist. She developed her own measuring table named Saruhashi's Table to determine the quantity of carbonic acid in water, based on temperature, pH level, and chlorinity. She was also a forerunner in nuclear research, developing methods to trace radioactive fallout across oceans. Her findings resulted in restrictions over oceanic nuclear experimentation in 1963.
In March 1954, a series of high-yield nuclear tests were conducted by the Joint Task Force of United States at Bikini Atoll. The occupants of a Japanese fishing trawler, which was downwind when the tests were carried out, were affected by the radiations. This prompted the Japanese government to ask the Geochemical Laboratory to examine and observe the levels of radioactivity it caused in the seawater and in rainfall. Dr Saruhashi worked on this to find that it took a year and a half for the radioactivity to reach Japan seawater. This was some of the first researches showing how the effects of fallout can spread across the globe.
In 1958, she established the Society of Japanese Women Scientists to promote women in the field of science. She was named executive director of Japan's Geochemical Laboratory in 1979. She was also the first woman to be elected to the Science Council of Japan. The first woman to win the Miyake Prize for geochemistry, Dr Saruhashi won the Avon Special Prize for Women, for her research in the area of peaceful uses of nuclear power and for raising the status of women scientists.
Having achieved much acclaim as a groundbreaking scientist, she instituted the Saruhashi Prize, awarded annually since 1981, for outstanding Japanese woman researchers.
Katsuko Saruhashi died on September 29, 2007 after battling pneumonia at her home in Tokyo. She was 87.