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OOISHI'S OBSERVATION

Viewed in the Context of Jet Stream Discovery

John M. Lewis

Although aircraft encounters with strong westerly winds during World War II provided the stimulus for postwar research on the jet stream, Wasaburo Ooishi observed these winds in the 1920s. Ooishi's work is reviewed in the context of earlier work in upper-air observation and postwar work on the jet stream. An effort is made to reconstruct Ooishi's path to the directorship of Japan's first upper-air observatory by reliance on historical studies and memoirs from the Central Meteorological Observatory.

Archival records from Japan's Aerological Observatory have been used to document Ooishi's upper-air observations. The first official report from the observatory (written in 1926 and in the auxiliary language of Esperanto) assumes a central role in the study. In this report, data are stratified by season and used to produce the mean seasonal wind profiles. The profile for winter gives the first known evidence of the persistent strong westerlies over Japan that would later become known as the jet stream.

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John M. Lewis

Philip Thompson (1922–94) pioneered innovative approaches to weather analysis and prediction that blended determinism and probability. He generally posed problems in terms of simplified dynamics that were amenable to analytic solution. His preciseness in problem formulation and presentation in a forceful didactical manner are linked to his early home-schooling and experiences with a coterie of young intellectuals. Four of Thompson's contributions are examined with the intention of highlighting their impact on the current state of operational analysis and prediction.

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John M. Lewis

In the mid-1950s, amid heated debate over the physical mechanisms that controlled the known features of the atmosphere's general circulation, Norman Phillips simulated hemispheric motion on the high-speed computer at the Institute for Advanced Study. A simple energetically consistent model was integrated for a simulated time of approximately 1 month. Analysis of the model results clarified the respective roles of the synoptic-scale eddies (cyclones-anticyclones) and mean meridional circulation in the maintenance of the upper-level westerlies and the surface wind regimes. Furthermore, the modeled cyclones clearly linked surface frontogenesis with the upper-level Charney–Eady wave. In addition to discussing the model results in light of the controversy and ferment that surrounded general circulation theory in the 1940s–1950s, an effort is made to follow Phillips's scientific path to the experiment.

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John M. Lewis

The emigration of 11 young Japanese meteorologists to the United States following World War II is investigated. Their move is examined with the benefit of a historical backdrop that includes a study of the socioeconomic conditions in Japan and the education that they received at the University of Tokyo. Oral histories and letters of reminiscence from these scientists are used with standard source material to reconstruct the conditions of postwar Japan. The principal results of the study are that 1) these scientists were among the intellectual elite, because of the rigorous screening process in the Japanese educational system; 2) their scientific education was fundamentally grounded in traditional physics and a wide range of geophysical sciences; 3) they all experienced austere living conditions and poor job prospects in the war-torn Japanese economy; and 4) they made a strong scientific connection with U.S. researchers in the areas of numerical experimentation and numerical weather prediction, which facilitated their move to the United States.

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John M. Lewis

LeRoy Meisinger was a U.S. Weather Bureau meteorologist and aeronaut who worked vigorously to bring meteorology to the aid of aviation in the post–World War I period. He was killed at the age of 29 in a scientific ballooning accident that has been detailed in a companion paper by Lewis and Moore. Meisinger's personality and scientific profile are reconstructed by examination of his oeuvre, which contains research contributions augmented by popular articles in the magazines of the period.

Meisinger's personal characteristics were those of a quiet, scholarly man with strong interests in science, music, and art. His experiences as a Signal Corps weather officer during World War I inclined him toward a career in meteorology. While stationed at the Fort Omaha Balloon School, he became intrigued with the possibilities of using the free balloon as a platform for tracking air currents.

As a research meteorologist with the U.S. Weather Bureau after the war, Meisinger melded adventurous scientific ballooning with the more painstaking and arduous task of scrutinizing data from the limited upper-air network of kite stations. His principal research contribution was a form of differential analysis that extrapolated surface data to the 1- and 2-km levels by using climatological statistics from the upper-air network. The impressive line of research he pioneered at the bureau came to an immediate and abrupt end with his accidental death in 1924.

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John M Lewis

Meteorologist Carl-Gustaf Rossby is examined as a mentor. In order to evaluate him, the mentor–protégé concept is discussed with the benefit of existing literature on the subject and key examples from the recent history of science. In addition to standard source material, oral histories and letters of reminiscence from approximately 25 former students and associates have been used.

The study indicates that Rossby expected an unusually high degree of independence on the part of his protégés, but that he was exceptional in his ability to engage the protégés on an intellectual basis—to scientifically excite them on issues of importance to him. Once they were entrained, however, Rossby was not inclined to follow their work closely.

He surrounded himself with a cadre of exceptional teachers who complemented his own heuristic style, and he further used his influence to establish a steady stream of first-rate visitors to the institutes. In this environment that bristled with ideas and discourse, the protégés thrived.

A list of Rossby's protégés and the titles of their doctoral dissertations are also included.

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John M. Lewis

In the early 1930s, Heinz Lettau and Werner Schwerdtfeger made direct measurements of air motion in the lowest 4 km of the troposphere by using the manned free balloon as an instrumented platform. The experiment was motivated by Wilhelm Schmidt's and Ludwig Prandtl's work on Austausch (exchange) theory in the second and third decades of the twentieth century. As a prelude to investigating the Lettau–Schwerdtfeger experiment, historical developments that had bearing on the field program are reviewed. Following this review, the experiment is analyzed by 1) documenting the scientific goals, 2) discussing the strategy for data collection, 3) examining one flight in detail (the flight of 25 February 1934), and 4) summarizing results from the experiment. The paper ends with a retrospective view of Austausch theory.

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John M. Lewis

In the late 1960s, well before the availability of computer power to produce ensemble weather forecasts, Edward Epstein (1931–2008) developed a stochastic–dynamic prediction (SDP) method for calculating the temporal evolution of mean value, variance, and covariance of the model variables: the statistical moments of a time-varying probability density function that define an ensemble forecast. This statistical–dynamical approach to ensemble forecasting is an alternative to the Monte Carlo formulation that is currently used in operations. The stages of Epstein's career that led to his development of this methodology are presented with the benefit of his oral history and supporting documentation that describes the retreat of strict deterministic weather forecasting. The important follow-on research by two of Epstein's protégés, Rex Fleming and Eric Pitcher, is also presented.

A low-order nonlinear dynamical system is used to discuss the rudiments of SDP and Monte Carlo and to compare these approximate methods with the exact solution found by solving Liouville's equation. Graphical results from these various methods of solution are found in the main body of the paper while mathematical development is contained in an online supplement. The paper ends with a discussion of SDP's strengths and weaknesses and its possible future as an operational and research tool in probabilistic–dynamic weather prediction.

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SMAGORINSKY'S GFDL

Building the Team

John M. Lewis

Joseph Smagorinsky (1924–2005) was a forceful and powerful figure in meteorology during the last half of the twentieth century. He served as director of the Geophysical Fluid Dynamics Laboratory (GFDL) for nearly 30 yr (1955–83); and during his tenure as director, this organization substantially contributed to advances in weather forecasting and climate diagnostics/prediction. The purpose of this research is to explore Smagorinsky s philosophy of science and style of management which were central to the success of GFDL. Information herein comes from his early scientific publications, personal letters and notes in the possession of his family, several oral histories, and letters of reminiscence from scientists who worked within and outside GFDL.

The principal results of the study are that 1) early inspiration and development of Smagorinsky's scientific philosophy came from his contact with Jule Charney and Harry Wexler, 2) his doctoral dissertation ideally prepared him for appointment as director of the U.S. Weather Bureau's long-range numerical prediction project in 1955—the General Circulation Research Section (later renamed GFDL), 3) he masterfully assembled a team of researchers to attack the challenging problem of general circulation modeling, and 4) he exhibited an authoritarian style of rule tempered by protection of the scientists from disrupting outside influence while celebrating the elitism and esprit de corps that characterized the laboratory.

A list of Smagorinsky's management principles is found in the appendix. Several of these tenets have been interspersed in the main body of the paper in support of actions he took at GFDL.

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Vanda Grubišić
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John M. Lewis

The Sierra Wave Project was the first post–World War II (WWII) mountain meteorology field experiment in the United States designed to study mountain lee-wave phenomena. In its concept, design, organization, and execution, this Air Force–funded project served as an important predecessor of modern mesoscale field experiments proving clearly that mesoscale phenomena could be studied effectively by combining high-density ground-based and airborne observations. In this historical overview of the Sierra Wave Project, we set the scientific motivations for the experiment in their historical context, examine the coupling of the Air Force interests with the sport of soaring and the science of meteorology in this experiment, and evaluate the impact of the observational and theoretical programs of the Sierra Wave Project on the meteorological and aviation communities. We also provide a link to the related past investigations of mountain waves and an outlook for the future ones.

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