David Q. Wark, a research meteorologist at the National Environmental Satellite, Data, and Information Service of the National Oceanic and Atmospheric Administration (NOAA/NESDIS) and its predecessor organizations for 55 years, died of cancer 30 July 2002. He will be long remembered for his seminal contributions to the weather satellite program.
A pioneer in the use of satellite sensors to provide observations of the Earth's environment for application to weather forecasting and atmospheric science, Dr. Wark was noted for his brilliant insights, dedication, and exceptional scientific achievements. He developed many of the theoretical and experimental techniques on which NOAA's current multi- billion-dollar meteorological satellite program is based. In the 1960's and early 1970's, he and his NOAA colleague Donald Hilleary were the motivating force and principal investigators for the first satellite instruments dedicated to sounding the atmosphere for temperature and water-vapor. These instruments included the Satellite Infra-Red Spectrometer (SIRS)-A and -B and the Vertical Temperature Profile Radiometer (VTPR), which were flown on NASA's Nimbus satellites and NOAA's ITOS-D satellites, respectively. With colleague Henry Fleming, he formulated the radiative transfer equation that quantifies the spectral radiances of the Earth and its atmosphere (measured at satellite altitude) and inverted that equation mathematically to infer the atmospheric temperature profile from satellite-based measurements of those radiances. A difficulty they had to overcome was that the mathematical problem is ill-posed, i.e., it admits of an infinite number of solutions. They arrived at a unique solution via an innovative application of a-priori information on the atmospheric state. This work was described in the landmark 1965 Wark and Fleming paper in the American Meteorological Society's Monthly Weather Review. From that early period until just weeks before his death, Dr. Wark continued his work at the Office of Research and Applications in NOAA/NESDIS on developing advanced techniques for sounding the atmosphere from satellites.
Dr. Wark's work in remote sensing of the Earth's atmosphere and surface from weather satellites benefited from his skill both as a meteorologist and an astronomer. Most of his work was directed toward the goal of deducing vertical temperature and moisture profiles in the Earth's atmosphere, but he also proposed a method for obtaining cloud top altitudes using the oxygen A band. In the early days of this effort at NOAA/NESDIS and its predecessor agencies, Dr. Wark and others (most notably Dr. S. Fritz), assembled a remarkable group of internationally known scientists at NOAA to work on this pioneering effort and made Suitland, Maryland an exciting place to work. Included in this group of visiting scientists were G. Yamamoto, D. G. James, S. Twomey, and F. Saiedy. In addition to his own insights, Dr. Wark proved to have a remarkable facility for subdividing the complex temperature profiling problem into smaller component problems that the visiting and U.S. scientists could attack without interfering with each other. Despite his well-deserved reputation for having a formidable personality, he guided the development of the satellite temperature profiling field with tact, diplomacy, and scientific acumen. During this time, Dr. Wark also brought to NESDIS, and guided, a number of younger scientists who went on to establish reputations of their own in the fields of satellite remote sensing and satellite meteorology. These included J. Alishouse, L. Crone, D. Crosby, H. Fleming, H. Jacobowitz, L. McMillin, W. L. Smith, L. Stowe, and M. Weinreb.
A Fellow of the American Meteorological Society, Dr. Wark received numerous awards from various scientific organizations, including a Silver Medal and a Gold Medal from the U.S. Department of Commerce, the Medal for Exceptional Scientific Achievement from NASA, the 2nd Half-Century Award from the American Meteorological Society, the Lloyd V. Berkner Space Utilization Award from the American Astronautical Society, and the Robert M. Losey Award, from the American Institute of Aeronautics and Astronautics.
David Quentin Wark was born on 25 March 1918, in Spokane, Washington. He was the fourth and last child of Percival Damon Wark and Clara Belle (née Mackey) Wark. In 1921 his family moved to Altadena and Pasadena, California, where he lived until 1939. He attended Altadena Elementary School, Edison Elementary School, Washington Junior High School, Pasadena High School, and Pasadena Junior College. From 1938 to 1939, and again in the summer of 1940, he worked for the Associated Press and David Lawrence to earn money to resume his education. In 1939, he entered the University of California, Berkeley, from which he graduated with a BA in Astronomy with honors in May 1941.
From 1941 to 1942 he did graduate study in meteorology at the University of California, Los Angeles. He resumed graduate studies part time in 1948 at the University of California, Berkeley, while working full time at the U.S. Weather Bureau and graduated with a PhD in Astronomy in January 1959. He remembered those times as tough days driving back and forth to Berkeley and living in Half-Moon Bay.
Dr. Wark's professional career began in 1942 at the U.S. Naval Observatory, where he served as a Naval Officer until 1946. He then went to work for the U.S. Weather Bureau. He spent the first three years of that period in Istres, France, Frankfurt and Munich, Germany, and Cairo Egypt. From 1949 through 1958 he served at the Aviation Weather Forecast Office in San Francisco. He then moved to the U.S. Weather Bureau Office in Suitland, Maryland, where he worked from November 1958 until 3 July 1999, when he officially retired. He actually retired from NOAA because during this time, he saw the U.S. Weather Bureau become part of ESSA which, in turn, became a part the National Oceanic and Atmospheric Administration (NOAA) in 1970. But retirement did not stop his work or his contributions to science. In his last 3 years, Dr. Wark took a part-time post-retirement position at NOAA/NESDIS where he continued to work in the field he pioneered and to which he dedicated his life.
One could not ta1k to Dr. Wark for long without learning of his keen interest in sailing. He was especia1ly proud of his 4-year adventure in which took periodic time from work to sail around the world (from 1982--1986) on his 38' cutter the Capella. During this time he (and a crew of 2) spent almost an entire year on the open seas, beginning the trip at Solomons, Maryland, and including stops in Ft. Lauderdale, Cancun, Panama, Galapagos Islands, French Polynesia, Cooke Islands, Niue, Tonga, Fiji, Vanuatu, Australia, Christmas Islands, Mauritius, Reunion, South Africa, St Helena, Brazil, the Virgin Islands and back home again along the North Carolina coast. His meteorological interest showed in the detailed series of bucket temperatures he took on this trip. On his return he obtained the corresponding satellite measurements and made comparisons between his temperatures and the surface temperatures measured by the satellite. He often made comments about how rare a cloud-free sky was, at least in the vicinity of oceans. A few years later he circumnavigated the eastern half of the United States via rivers, inter-coastal waterways, and canals, a trip of approximately 2000 miles. This voyage ended in 1990, when he was 72 years of age. Some of the segments of this voyage he sailed single-handedly, a remarkable achievement.
This biography would not be complete without mentioning the famous cigars. Dr. Wark acquired a reputation among his colleagues for hardly ever being seen without a well-chewed cigar, damp on one end, lit on the other, in his hand. When computers were in their infancy, discs were not as well sealed as they are today, and the one in Dr. Wark's office seemed to experience an inordinate frequency of failures. Finally, in exasperation, he decided to investigate. On pulling the disc out and examining it with a microscope, he observed a speck of cigar ash that had landed on the disc's surface and scratched it. From that time on, although he was seldom seen without a tattered cigar, it was never lit when he was in his office.
Dr. Wark was dedicated to his parents and the field of meteorology. This dedication was demonstrated when he provided a generous donation to the AMS to establish the Percival D. Wark and Clara B. (Mackey) Wark Scholarship. This is an annual scholarship to be awarded to a student majoring in atmospheric or related oceanic and hydrologic sciences.
Dr. Wark is survived by his nephew Walter Damon Wark of no fixed address, and his great nephew Christopher Hal Wark of Fresno, California. His two brothers, Francis Walter and Robert Damon, as well as his sister, Dorothy Marie (née Wark) Schaertl, pre-deceased him.
Photo courtesy of NOAA