David Atlas: 1924-2015.
A member of Tom Brokaw's "Greatest Generation," Dave was born on May 25, 1924, the third child of Rose Jaffee Atlas and Isadore Atlas, immigrants from Russia and Poland, respectively. His family was of less than modest means, though there was always food on the table. The extended family formed a closeknit clan centered mostly in the East New York section of Brooklyn. Dave did well in public school, revered his teachers, and was highly motivated by them. He finished public school early, graduating at age 16, while editing the Spanish magazine and presiding over the Pan American Club. Dave's attempts to play the accordion led to the realization he had no natural talent for it. Later in life Dave would marry Lucille Rosen, and together they would raise a son, Robert, and a daughter, Joan.
Atlas planned to be an electrical engineer when he entered the City College of New York, where his special joy was freshman physics. As a student, Dave held a job at Western Electric, where he worked on a production line for the munificent salary of $35 per week, nearly as much as his father. The events of December 7, 1941, changed his plans, as well as those of millions of people around the world. Atlas accelerated his education with a heavy course load and summer school, expecting to join the military in some capacity. Soon thereafter, Dave applied to premeteorology training in the Army Air Corps, despite not knowing exactly what meteorology entailed. He was rejected, so he reapplied giving the same information and was accepted. Prior to this, he apparently had little if any interest in meteorology.
He reported for active duty at New York University, where Louis Battan became his roommate, best man, and lifetime friend and colleague. Dave finished first in his class and was commissioned second lieutenant in 1944. Thereafter, the Weather Instrument Training School introduced Dave to basic electronics as preparation for Harvard/MIT Radar School. An event, of which he had no knowledge, was the invention of radar in the mid-1930s. A major factor setting the stage for his career was the GI bill, which provided financial assistance that led to his earning the D.Sc. in 1955 from MIT while also working as chief of the Weather Radar Branch at the Air Force Cambridge Research Laboratory (AFCRL). A mere two years later he received the Meisinger Award, his reputation having grown by leaps and bounds in what was now broadly recognized as an exciting new branch of meteorology. A man who set out to become an electronics engineer was drawn into meteorology by his assignment to service in war. As it turned out, the multidisciplinary education and training that he received had prepared him ideally for the emerging field of radar meteorology. Dave used his innate talents and a lot of hard work to accomplish the rest.
Atlas's achievements are the consequence of his many qualities, which included his persistence, intellect, creativity, enthusiasm, and love for science. As a taskmaster, there is little doubt he elevated the accomplishments of others to levels they might not otherwise have achieved. Another factor shaping his career is perhaps best described as "serendipity," a term often used by Dave. In his memoir, Dave commented, "I also began to realize that one had to be opportunistic and flexible to exploit events when they occurred."
Among Atlas's early and very significant accomplishments was his invention of the isoecho contour mapping concept. This occurred in 1947, while he was a member of the All Weather Flying Division at Clinton Air Force Base in Wilmington, Ohio. A patent was granted in 1953. The isoecho contour method was the first to quantize and therefore quantify weather radar reflectivity information on cathode ray tubes. This relatively simple concept received widespread use for decades on commercial aircraft and ground-based operational weather radars, and by the research community. It was not until the advent of color displays in the early 1970s that isoecho displays began to be replaced. Indeed, there were many airline pilots who objected strongly to the loss of the traditional CRT displays when color technology became available. By the age of 24, David Atlas was hooked on science and technology.
Dave recruited Roger Lhermitte from France to AFCRL. Their early collaborations with Doppler Radar led to outstanding discoveries. On the occasion of the first Doppler Velocity Azimuth Display measurements, Lhermitte attached an audio speaker to the Doppler output. Dave said, "To our astonishment and exquisite pleasure on 2 December 1957, we heard and tape recorded the Doppler shift as it varied in pitch from near-zero frequency when it was pointed crosswind, to high frequencies when it was pointing either up- or downwind." This set the stage for several decades of Doppler radar research and development, and ultimately operational applications. Somewhat to Dave's dismay, the United States was unable to install a national Doppler radar network until the 1990s. This was in turn followed by the deployment of airport terminal Doppler radars. These two operational radar systems have dramatically improved short-term weather warnings and saved thousands of lives and billions of dollars of damage.
In 1972, Atlas joined the National Center for Atmospheric Research (NCAR), where he was the founding director of the Atmospheric Technology Division (ATD), which provided a broad range of observational and computational facilities for research community use. Atlas brought a vision to NCAR that included a state-of-the-art array of next-generation observing facilities. There would be Doppler radars, automated surface stations, next-generation sounding systems, lidars, acoustic sounders, and new airborne instruments, including an airborne Doppler radar. Dave's major contributions were to get the ball rolling by articulating his vision and hiring several key staff, including Robert Serafin, who in turn hired Richard Carbone and several others.
Within two years there were two transportable C-Band Doppler radars that became a mainstay of university research for about two decades. The Portable Automated Mesonetwork (PAM) was the first fully automated mesonet reporting its data via radio telemetry and later via satellite. The new radars and PAM helped to transform the way in which field experiments were conducted because the real-time data displays greatly facilitated knowledge of "present weather." This led to improved understanding of the initiation, growth, and decay of convective storms, extratropical cyclones, tropical rainfall, and other phenomena. The detection of hazardous wind shear and microbursts using these radars led to agency deployment of Doppler radars for aviation safety in the United States and internationally, undoubtedly saving countless lives.
After two years at the helm of ATD, Dave was asked to assume leadership of the National Hail Research Experiment (NHRE). NHRE was a weather modification program aimed at demonstrating the effectiveness of hail suppression, initially motivated by claims of success in the Soviet Union. After several years of field experimentation, it appeared to Atlas that no positive effect on the suppression of hail would be detectable, if only because of the great natural variability of hailstorms. To the dissatisfaction of the weather modification community, Dave felt strongly that experimental evidence was sufficient to stand down from cloud seeding to analyze existing data and reexamine the basic hypotheses for hail suppression. Faced with federal program manager resistance, Dave resigned from the NHRE directorship as a matter of principle--later to be vindicated by major NHRE successes, gained from new understanding of deep moist convection more generally, while statistically failing to suppress hail.
During his tenure at NCAR, Dave was elected as AMS president. His term was marked by a focus on atmospheric science and public policy. As president-elect in 1974, Dave and Lucille were included in the first postcultural revolution scientific delegation to the Peoples Republic of China. This historical visit was the forerunner of decades of scientific collaboration between the two countries.
In 1977, Dave left NCAR for the Goddard Space Flight Center (GSFC), where he was given carte blanche to build a new laboratory, the Goddard Laboratory for Atmospheric Sciences (GLAS). He established a new vision for atmospheric research programs there. Dave placed scientific excellence at the top of his priorities, attracting 35 new scientists to GLAS, including Michael King, Joanne Simpson, Louis Uccellini, Antonio Busalacchi, and many others who became prominent in their respective fields. Dave's interests quickly broadened to encompass the full spectrum of active and passive remote sensing of the atmosphere, oceans, and Earth's surface. Dave played a prominent role in defining the Tropical Rainfall Measuring Mission (TRMM), working closely with Joanne Simpson and colleagues from Japan to implement the first meteorological radar in space. TRMM has provided unprecedented detail on the structure and distribution of rainfall and improved estimation of cumulative rainfall over tropical oceans--information essential for understanding Earth's energy budget and water cycle.
Among Dave's principal written legacies is Radar in Meteorology (published by AMS in 1990), produced and edited from proceedings at the Louis Battan Memorial and 40th Anniversary Radar Meteorology Conference. Battan died in 1986, having been an outstanding educator, researcher, and leader in the field. The conference format was designed by Dave, working closely with the AMS Committee on Radar Meteorology, chaired by Richard Carbone. Tutorial papers were written and delivered by the foremost experts in the field. Owing to Dave's dogged determination and prodding of authors, Radar in Meteorology contains the most comprehensive collection of contributions that has ever been produced under one cover in radar meteorology.
It is informative to examine Atlas's extensive publication record from the viewpoint of peer interest in his work. Among more than 230 papers, the most highly cited works span a period of 40 years, from 1953 to 1993. These papers originated in similar proportion at each of Atlas's principal "venues"--AFCRL, the University of Chicago, NCAR, and GSFC. The most frequently cited publication overall is Advances in Radar Meteorology (1964), the first textbook-type of publication that reviewed Doppler signal theory in depth. Advances served as a treasure chest of empirical relationships among reflectivity factor, attenuation, water content, and rainfall rate, and presented some novel interpretations of the radar equation, complications of Mie scattering, and multiple wavelength responses to hydrometeors.
Four broad categories of papers are prevalent in the Atlas contributions:
* Microwave scattering and attenuation properties of hydrometeors
* Techniques for reduction of bias and uncertainty in radar rainfall estimation
* Studies related to atmospheric turbulence and mesoscale air flow
* Studies related to radar echoes in optically clear air
Atlas retired from NASA in 1984. Although formally retired from government service, his enthusiasm for science and discovery never waned, remaining strong for his entire life. After retirement, Dave contributed substantially to the understanding of tropical rainfall processes through his many collaborative papers on TRMM-related topics. He became interested in microburst and wind shear detection for aviation safety and invented and patented a technique through which low-level wind shear could be detected with fan-beam air traffic control radars at airports.
A man who set very high professional standards was also a man with great compassion for the lives of others, a man who would do almost anything to help a friend. He touched the lives of hundreds--perhaps thousands--of people worldwide. He loved his wife, children, and grandchildren. He skied (water and snow) and played tennis. His curiosity extended to spirituality and religion. There are many of us who can make the claim to have been a friend and colleague of Dave Atlas, a privilege and honor that we cherish greatly.
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|Title Annotation:||45 BEACON: OBITUARIES|
|Author:||Serafin, Robert J.; Carbone, Richard E.|
|Publication:||Bulletin of the American Meteorological Society|
|Date:||Jun 1, 2016|
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