Special Issue—Scripps Centennial Climate and Atmospheric Science at Scripps: the Legacy of Jerome Namias
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81832_Ocean 8/28/03 7:34 PM Page 93 Special Issue—Scripps Centennial Climate and Atmospheric Science at Scripps: The Legacy of Jerome Namias Richard C.J. Somerville 5912 LeMay Road, Rockville, MD 20851-2326, USA. Road, 5912 LeMay prohibited. Send all correspondence or Society is strictly to: [email protected], The Oceanography machine, reposting, or other means without prior authorization of portion photocopy of this articleof any by All rights reserved.Reproduction Society. The Oceanography 2003 by Copyright Society. The Oceanography journal 16, Number 4, a quarterly of Volume This articlein Oceanography, has been published Scripps Institution of Oceanography, University of California • San Diego, California USA Jerome Namias (1910–1997) pioneered the art and highs and lows gliding over the surface of the earth. science of long-range weather forecasting. He also set Even during the darkest periods of the Cold War, off the modern era of research in climate and atmos- nations that could agree on little else continued to pheric science at Scripps Institution of Oceanography. exchange weather data. The atmosphere does not heed Largely self-taught, Namias developed an exceptional national borders, so a storm over Siberia today may physical intuition for the intricate interplay between produce heavy snow in Chicago within a few days. atmosphere and ocean. In an era when the skill of Weather forecasting is far too important economically weather forecasts was limited to two or three days, to be held hostage to politics. Climate research has ben- Namias advocated the heretical notion that climate, the efited enormously from the immense archive of weath- sum total of weather, might be predictable for weeks, er data extending back into the nineteenth century. This months, or even longer. He was among the first to real- archive must be among the largest data sets in all of sci- ize that planetary-scale air-sea interactions strongly ence. Namias’s work relied entirely on this long-term influence climate variability and thereby make certain, monitoring of the state of the global atmosphere, paid specialized types of predictions possible far beyond the for by the massive data requirements of weather pre- time horizon of ordinary weather forecasts. diction, and available essentially at no cost to climate Namias’s greatest strength as a scientist was his researchers. ability to develop profound insights by analyzing For many years at Scripps, Namias routinely issued enormous amounts of observational data. His data forecasts of how the climate in the season to come included measurements of conventional meteorologi- might be expected to differ from the climatological cal variables such as winds, air temperatures, and average. Namias was interested in the big picture, not atmospheric pressures, as well as measurements of in local details. He was one of the first to appreciate the oceanographic parameters, especially sea-surface tem- concept of teleconnections, a term connoting the ability peratures. Throughout most of his long career, of climate phenomena in one region of the earth to Namias’s office walls were covered with maps and influence other regions thousands of miles away. An charts of these data, covering huge areas, typically early form of these forecasts was a series of maps of the much of the Northern Hemisphere. From this empiri- United States colored to show areas where average cal material, Namias was able to infer mechanistic temperature and precipitation were predicted to be interconnections between air and sea, between phe- above normal, near normal, or below normal. For many nomena in one part of the world and those in another, years, Namias’s winter predictions were presented to and between the evolution of these fields in the recent the public with considerable fanfare at a press confer- past and their probable course in the future (Figure 1). ence held annually in early December. A certain degree of theatrical suspense inevitably accompanied the Global Climate at the Local Level media treatment of perfectly natural questions, such as Although his scientific interests were wide rang- “When will the current drought end?” Namias clearly ing, Namias was a synoptic meteorologist at heart; that relished his starring role in these productions. is to say, a scientist interested in understanding and In hindsight, these seasonal predictions were often predicting the large-scale features of atmospheric cir- marred by significant errors. Nevertheless, Namias’s culation. Synoptic meteorology deals with aspects of verbal explanations, detailing how and why the large- the atmosphere that can be revealed by simultaneous scale patterns of atmospheric circulation could be measurements made throughout the earth by a global expected to evolve, were always fascinating and observing system. By international agreement, such a insightful, to both scientists and the media as well as to system has actually been in place for many decades. the public. The same was true of his explanations after This system provides the raw data to satisfy the daily the fact of why a given forecast had been right or computational needs of operational weather predic- wrong. For Namias, a failed forecast was just a learning tion. It is these data that depict the continental-scale opportunity. Oceanography • Vol. 16 • No. 3/2003 93 81832_Ocean 8/28/03 7:34 PM Page 94 nology and to ignore empiricism. He also had little sympathy for purely statistical approaches to forecast- ing. Always courteous, he was nevertheless fond of pointing out unrealistic features of numerical climate model results and suggesting gently that “the kids with the computers” needed to rethink their equations. Namias respected the power of computational methods but inevitably viewed them as adjuncts to human fore- casters and never as replacements for physical thinking. Namias was far ahead of his time in identifying and recognizing the importance of many new concepts and phenomena in atmospheric science. He was also a prolific and instructive author, and the numerous case studies he analyzed and published are well worth Figure 1. Jerome Namias (center) at Scripps in the studying today. Although Namias himself loved fore- early days. casting and was intellectually addicted to it, the insights displayed in his observational analyses are of more lasting scientific value than the successes and failures of his individual predictions. Figure 2. Jerome In fact, the seasonal forecasts themselves, particu- larly the more successful ones, may best be regarded as Namias in La Jolla. constituting an unusual kind of challenge to Namias’s more theoretically inclined colleagues. They represent a special type of existence proof: If Namias could study a wall full of maps of observational data and thereby produce a skillful seasonal forecast, then surely it ought to be possible to construct a mathematical model to make such a climate forecast deductively and objec- tively, preferably from first principles—in the same sense that the existence of human chess grandmasters is a challenge to people who build chess-playing com- puter programs. In climate research, as in chess, computer pro- grams have greatly improved in recent years. Unlike There is no doubt that part of the widespread pop- chess, however, climate is a subject whose scope rapid- ular appeal of climate prediction is its ambitious nature ly expands as time goes on. Therefore, today we seek to and global scale. The very idea that an immense and develop models that can not only predict the next El unusually warm sector of the Pacific Ocean in the fall Niño, but can also foretell how increasing amounts of season, for example, could somehow lead to a change atmospheric carbon dioxide will change the climate of in atmospheric circulation that in turn could produce the coming century (Figure 2). an unusual pattern of precipitation over North America the following winter is inherently fascinating. An Unconventional Biography In describing the continuous drama taking place in the For a first-rank scientist, Namias had an unconven- atmosphere and ocean, Namias’s fertile mind saw the tional biography. He was a weather enthusiast from action as playing out on a truly global stage. childhood. Illnesses and economic difficulties in his For his seasonal predictions, Namias relied on youth kept him from pursuing a conventional educa- methods that were not technically sophisticated and tional and career path. Instead, he took correspondence were often surprisingly subjective. Mathematically, his courses, read voraciously, held a variety of jobs, and toolbox was mainly limited to simple statistical tech- benefited from personal contacts with leading scientists niques that could show how the space-time patterns of of the time, whom he actively sought out after studying various climate variables were correlated with one their papers. Although Namias eventually received another. In fact, Namias took pride in making forecasts honorary doctorates and many other awards, his only subjectively, based on insight, analogy to past events, earned degree was a master’s from the Massachusetts and qualitative physical reasoning, and he often regard- Institute of Technology (MIT), which he received at the ed numerical simulations of climate as his competition. age of 31. Namias is surely unusual and perhaps unique Throughout his career, Namias was openly dis- among members of the National Academy of Sciences dainful of what he perceived as a tendency in some in that he earned neither an undergraduate university mathematical modelers to lose themselves in their tech- degree nor a Ph.D. Oceanography • Vol. 16 • No. 3/2003 94 81832_Ocean 8/28/03 7:34 PM Page 95 As a graduate student at MIT in the early months of World War II, Namias was involved in a project investigating the feasibility of long- range weather forecasts. At the time, “long range” meant five days, and con- ventional wisdom was that skillful forecasts at such a range were impossi- ble. Nevertheless, the potential mili- tary importance of such forecasts was enormous, and Namias took leave from MIT to go to Washington to lead a project pursuing this topic.