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Sears, Mary (1905–1997)

Sears, Mary (1905–1997)

One of the foremost American oceanographers of the 20th century. Born on July 18, 1905, in Wayland, Massachusetts; died on September 2, 1997, in Woods Hole, Massachusetts; attended the Winsor School in Boston; Radcliffe College, B.S., 1927, M.S., 1929; never married; no children.

On October 19, 2000, the U.S. Navy launched its sixth oceanographic survey ship in the Pathfinder class, 329 feet long and designed for surveying both deep ocean and coastal waters. The first Navy oceanographic ship to be named after a woman, the USNS Mary Sears honors one of the premier oceanographers of the 20th century. Mary Sears began her career at a time when women were barred from sailing on research and Navy vessels, but she nonetheless became one of the guiding lights of the Woods Hole Oceanographic Institute as well as the "first oceanographer of the Navy in modern times." This description by her colleague Roger Revelle refers to Sears' wartime work with the Navy, when, as a WAVE, she organized an oceanographic unit that helped American submarines avoid detection by the enemy.

Born in Wayland, Massachusetts, in 1905, Sears was educated at the Winsor School in Boston before attending Radcliffe College in Cambridge, from which she received a bachelor's degree (1927) and master's degree (1929). In 1932, while pursuing a Ph.D. in zoology at Radcliffe, she became one of the first staff research assistants at the newly founded Woods Hole Oceanographic Institute in Cape Cod. After receiving her doctorate in 1933, she worked as a research assistant at Harvard (1933–49) and an instructor at Wellesley College (1938–43), spending her summers working at various capacities at Woods Hole before 1940, when she received a year-round position there as a staff planktonologist.

In 1943, as World War II raged, Sears was commissioned a lieutenant j.g. (junior grade) in the WAVES—the U.S. Navy's women's branch—and began working at the Navy Hydrographic Office in Washington, D.C. There she founded and became head of the small Oceanographic Unit, where research from Woods Hole was used to aid submarines and warships. Her discovery that thermoclines, areas of water subject to rapid temperature changes, could be used to hide submarines from radar was of huge importance to the war effort. The Oceanographic Unit grew until it eventually took over the entire Hydrographic Office (which had previously focused on creating navigational charts); it was then renamed the Naval Oceanographic Office. In 1946, after the war had ended, Sears received a Rask-Orsted Foundation grant which enabled her to work for a year in Copenhagen, where she was awarded the Johannes Schmidt medal for her oceanographic war work. The following year she transferred to the Naval Reserve and returned to work at Woods Hole.

Over the next several decades, Sears edited some of the most important publications in the field of oceanography, helping to found the journals Progress in Oceanography and Deep-Sea Research, the latter of which she served as editor from 1953 to 1974; she also edited Oceanography (1961) and, with Daniel Merriman, Oceanography: The Past (1980), two books that are considered benchmarks in the field. In 1959, she was chair of the First International Congress on Oceanography, held at the United Nations in New York City. She also edited the annual reports and research summaries of Woods Hole from 1962 through 1973. In 1963, Sears retired from the Naval Reserve as a commander and became a senior scientist in the biology department at Woods Hole. She retired seven years later, but remained active at the institute, continuing to compile its annual collected reprints as she had since 1959, and organizing the Oceanographic Index until 1976. In 1978, she was named a scientist emeritus at Woods Hole.

Mary Sears was the recipient of a number of awards over the years, including honorary doctorates from Mt. Holyoke College (1962) and the University of Massachusetts at Dartmouth (1974), and an Alumnae Recognition Award from Radcliffe College (1992). In 1985, on the occasion of her 85th birthday, Deep-Sea Research dedicated an issue to her. She was also a fellow of the American Association for the Advancement of Science. A longtime resident of Falmouth, Massachusetts, Sears was active in the community, serving as a member of the Falmouth Town Meeting for 35 years and of the town's school committee for over 20 years. She was also the committee chair of the Children's School of Science at Woods Hole. In 1996, she attended the retirement party for Woods Hole's Atlantis II research vessel, which she had christened in the 1930s. She died the following year at age 92.


The Cape Cod Times. November 17, 1999; October 20, 2000.

The Day [New London, CT]. September 7, 1997; September 10, 1997.

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