Carl-Gustaf Arvid Rossby (born December 28, 1898, and died August 19, 1957) was a scientist who studied weather and was born in Sweden but worked in the United States. He was the first to explain how the atmosphere moves on a large scale using the study of how liquids and gases move. He discovered and described the jet stream and the long waves in the westerly winds, which are now called Rossby waves.

Biography

Carl-Gustaf Rossby was born in Stockholm, Sweden. He was the first of five children born to Arvid and Alma Charlotta (Marelius) Rossby. He attended Stockholm University, where he developed an early interest in mathematical physics. Rossby began studying meteorology and oceanography while learning geophysics under Vilhelm Bjerknes at the Geophysical Institute at the University of Bergen in Norway in 1919. Bjerknes’ group was working on new ideas that became known as the Bergen School of Meteorology, including the theory of the polar front.

He also studied at the University of Leipzig and at the Lindenberg Observatory (Meteorologisches Observatorium Lindenberg) in Brandenburg, where researchers studied how to measure air conditions using kites and balloons. In 1921, he returned to Stockholm to join the Meteorological and Hydrographic Office (which later became the Swedish Meteorological and Hydrological Institute). There, he worked as a meteorologist on several oceanographic expeditions. During breaks between trips, he studied mathematical physics at Stockholm University and earned a degree in 1925.

In 1925, Rossby received a fellowship from the Sweden-America Foundation to study how the polar front theory could explain American weather. In the U.S. Weather Bureau in Washington, D.C., he combined research on atmospheric turbulence with creating the first weather service for civil aviation. In 1928, he became an associate professor in the Aeronautics Department at the Massachusetts Institute of Technology (MIT). Soon after, MIT established the first meteorology department in the United States. In 1931, he also became a research associate at the Woods Hole Oceanographic Institution. His work during this time included studying atmospheric thermodynamics, mixing and turbulence, and how oceans and the atmosphere interact.

On January 9, 1939, Rossby became an American citizen. That same year, he was named assistant director of research at the U.S. Weather Bureau. In 1940, he became chair of the meteorology department at the University of Chicago. This marked the start of his focus on large-scale movements in the atmosphere, during which he identified and described the jet stream and Rossby waves.

During World War II, Rossby trained military meteorologists. After the war, he brought many of them to his Chicago department, where he used electronic computers to improve weather forecasting. He had started this work in Sweden using a computer called BESK. In 1947, he became founding director of the Swedish Meteorological and Hydrological Institute (SMHI) in Stockholm. He divided his time between Stockholm, the University of Chicago, and the Woods Hole Oceanographic Institution. After the war, he visited his friend Professor Hans Ertel in Berlin. Their collaboration helped create the mathematical description of Rossby waves.

Between 1954 and his death in Stockholm in 1957, Rossby worked to develop the field of atmospheric chemistry. His contributions to meteorology were highlighted in a December 17, 1956, issue of Time magazine. His portrait appeared on the magazine’s cover, making him the first meteorologist to be featured on the cover of a major publication. During this time, he studied how carbon dioxide in the atmosphere might cause warming.

Selected works

• The layer of wind and ocean current movement affected by friction (Massachusetts Institute of Technology and Woods Hole Oceanographic Institution) – 1935
• Weather predictions based on local atmospheric data: An early study (Institute of Meteorology of the University of Chicago) – 1942
• Movement and pressure characteristics of long waves in westward-moving winds (Institute of Meteorology of the University of Chicago) – 1942

Honors

• Was chosen as a member of the American Academy of Arts and Sciences in 1934
• Was chosen as a member of the United States National Academy of Sciences in 1943
• Received the Sylvanus Albert Reed Award from the Institute of the Aeronautical Sciences in 1934 (awarded together with H. C. Willett)
• Served as president of the American Meteorological Society from 1944 to 1945
• Was chosen as a member of the American Philosophical Society in 1946
• Received the Robert M. Losey Award from the Institute of the Aeronautical Sciences in 1946
• Received the Symons Gold Medal from the Royal Meteorological Society in 1953
• Received the International Meteorological Organization Prize from the World Meteorological Organization in 1957
• Received the Applied Meteorology Award from the American Meteorological Society in 1959

Other sources

• Horace R. Byers ─ Carl-Gustaf Arvid Rossby. 1898–1957. A story about his life (National Academy of Sciences)
• Norman A. Phillips ─ A special meeting to celebrate the 100th anniversary of Carl-Gustaf A. Rossby’s birth (American Meteorological Society)