Search Results
You are looking at 1 - 10 of 11 items for :
- Author or Editor: J. M. Lewis x
- Bulletin of the American Meteorological Society x
- Refine by Access: All Content x
Ira Sprague Bowen (1898–1973) was a prominent astrophysicist during the twentieth century. In his impressive oeuvre of work over the 50-year span (1920–70), there appears a lone contribution to the geophysical sciences on the subject of evaporation and conduction from water surfaces. This theoretical development led to an expression for the ratio of heat conduction to evaporative flux at the air–water interface, labeled the Bowen ratio by Harald Sverdrup in the early 1940s. The circumstances that led to this contribution are examined with attention to the character of education and research at the California Institute of Technology during the 1920s. Bowen was unaware of the important precedent work in meteorology and fluid dynamics that is also reviewed.
Ira Sprague Bowen (1898–1973) was a prominent astrophysicist during the twentieth century. In his impressive oeuvre of work over the 50-year span (1920–70), there appears a lone contribution to the geophysical sciences on the subject of evaporation and conduction from water surfaces. This theoretical development led to an expression for the ratio of heat conduction to evaporative flux at the air–water interface, labeled the Bowen ratio by Harald Sverdrup in the early 1940s. The circumstances that led to this contribution are examined with attention to the character of education and research at the California Institute of Technology during the 1920s. Bowen was unaware of the important precedent work in meteorology and fluid dynamics that is also reviewed.
In response to the needs of the ocean traders and military shipping during the nineteenth century, Matthew Maury (1806–73) and Wladimir Köppen (1846–1940) worked in tandem to create wind charts for the World Ocean. In the early part of the century, Maury organized and supervised the production of the Wind and Current Charts for all navigable seas. In the latter part of the century, Köppen simplified these charts by use of a synoptically innovative stratification of the data, and these analyses became centerpieces of the Segelhandbiicher (Sail Handbooks) produced by the German Marine Observatory (Seewarte).
The charts produced by each of these men are examined in an effort to clarify their separate but unique contributions. Maury and Köppen were complementary in their approach to marine meteorology: Maury possessed organizational skills and an empirical approach to science, while Köppen was more academic and interested in the basic sciences. Köppen's exceptional background in both physics and biology was instrumental to his success in simplifying Maury's charts. These appealing synoptic charts served Bergeron in his quest for a global understanding of air masses and ultimately gave Köppen a viewpoint on climatology that embraced the entire world.
In response to the needs of the ocean traders and military shipping during the nineteenth century, Matthew Maury (1806–73) and Wladimir Köppen (1846–1940) worked in tandem to create wind charts for the World Ocean. In the early part of the century, Maury organized and supervised the production of the Wind and Current Charts for all navigable seas. In the latter part of the century, Köppen simplified these charts by use of a synoptically innovative stratification of the data, and these analyses became centerpieces of the Segelhandbiicher (Sail Handbooks) produced by the German Marine Observatory (Seewarte).
The charts produced by each of these men are examined in an effort to clarify their separate but unique contributions. Maury and Köppen were complementary in their approach to marine meteorology: Maury possessed organizational skills and an empirical approach to science, while Köppen was more academic and interested in the basic sciences. Köppen's exceptional background in both physics and biology was instrumental to his success in simplifying Maury's charts. These appealing synoptic charts served Bergeron in his quest for a global understanding of air masses and ultimately gave Köppen a viewpoint on climatology that embraced the entire world.
The California Institute of Technology (Cal Tech) established a course of study in meteorology in 1933. It was intimately tied to the upsurge of activity in commercial and military aviation that occurred in the period between the world wars. The tragic crash of the airship U.S.S. Akron provided the stimulus for including meteorology as a subprogram in the aeronautics department at Cal Tech. Theodore von Kármán, head of the department and director of the school's Guggenheim Aeronautics Laboratory, masterminded the design of the program and geared it toward the solution of practical problems using the principles of dynamic meteorology. One of his doctoral students, Irving Krick, was groomed to develop the program.
Robert Millikan, head of the institute, fostered an approach to science that encouraged the faculty to consult and work with industry. In this environment, Krick established links with aviation, motion picture studios, and public utilities that would set the stage for the research thrust in meteorology. The program was primarily designed for training at the master's degree level, and a significant number of the graduates became entrepreneurs in meteorology. Based on letters of reminiscence and oral histories from some of these consulting meteorologists, it has been concluded that the Millikan/von Karman philosophy of science played an important part in directing the meteorologists into the private sector.
Following World War II, Lee DuBridge replaced Millikan as head of the institute. DuBridge's efforts were directed toward making the small elite school scientifically competitive in the changed conditions of a postwar world. In this climate, the merging of private business with academic work fell into disfavor. Without champions such as Millikan and von Karman, the meteorology program was unable to survive.
The California Institute of Technology (Cal Tech) established a course of study in meteorology in 1933. It was intimately tied to the upsurge of activity in commercial and military aviation that occurred in the period between the world wars. The tragic crash of the airship U.S.S. Akron provided the stimulus for including meteorology as a subprogram in the aeronautics department at Cal Tech. Theodore von Kármán, head of the department and director of the school's Guggenheim Aeronautics Laboratory, masterminded the design of the program and geared it toward the solution of practical problems using the principles of dynamic meteorology. One of his doctoral students, Irving Krick, was groomed to develop the program.
Robert Millikan, head of the institute, fostered an approach to science that encouraged the faculty to consult and work with industry. In this environment, Krick established links with aviation, motion picture studios, and public utilities that would set the stage for the research thrust in meteorology. The program was primarily designed for training at the master's degree level, and a significant number of the graduates became entrepreneurs in meteorology. Based on letters of reminiscence and oral histories from some of these consulting meteorologists, it has been concluded that the Millikan/von Karman philosophy of science played an important part in directing the meteorologists into the private sector.
Following World War II, Lee DuBridge replaced Millikan as head of the institute. DuBridge's efforts were directed toward making the small elite school scientifically competitive in the changed conditions of a postwar world. In this climate, the merging of private business with academic work fell into disfavor. Without champions such as Millikan and von Karman, the meteorology program was unable to survive.
Carl-Gustaf Rossby (1898–1957) was chosen to head the first U.S. program in modern meteorology at the Massachusetts Institute of Technology (MIT) in 1928. The steps that led to this appointment are briefly reviewed as well as the academic environment at MIT in the early 1930s. It has been argued that Rossby's development as a research scientist was closely tied to his connection with oceanographers at the Woods Hole Oceanographic Institution. His work on geostrophic adjustment, an outgrowth of his research on the Gulf Stream, was marked by bold simplification of the governing dynamical equations. This allowed him to capture the essence of adjustments between pressure and velocity in unbalanced geophysical flow. His work on the adjustment problem is summarized and related to earlier work by Ekman and Margules.
Carl-Gustaf Rossby (1898–1957) was chosen to head the first U.S. program in modern meteorology at the Massachusetts Institute of Technology (MIT) in 1928. The steps that led to this appointment are briefly reviewed as well as the academic environment at MIT in the early 1930s. It has been argued that Rossby's development as a research scientist was closely tied to his connection with oceanographers at the Woods Hole Oceanographic Institution. His work on geostrophic adjustment, an outgrowth of his research on the Gulf Stream, was marked by bold simplification of the governing dynamical equations. This allowed him to capture the essence of adjustments between pressure and velocity in unbalanced geophysical flow. His work on the adjustment problem is summarized and related to earlier work by Ekman and Margules.
Out of the nearly 6000 U.S. military officers who were trained to be weather forecasters during World War II, there were approximately 100 women. They were recruited into the Women Accepted for Volunteer Emergency Service (WAVES) by the U.S. Navy and underwent training with the military men in the so-called cadet program. Letters of reminiscence from six WAVES forecasters are combined with official navy correspondence, archival information from universities, and newspaper articles of the period to reconstruct the recruitment, training, duty assignments, and postwar careers of these women.
With limited information, an effort has also been made to document the training of civilian women in the cadet program, and to estimate the number of women who served as forecasters in foreign countries during the war. The status of women in meteorology prior to the United States' entry into the war is examined as a backdrop to the study. Principal results of the study are as follows:
Out of the nearly 6000 U.S. military officers who were trained to be weather forecasters during World War II, there were approximately 100 women. They were recruited into the Women Accepted for Volunteer Emergency Service (WAVES) by the U.S. Navy and underwent training with the military men in the so-called cadet program. Letters of reminiscence from six WAVES forecasters are combined with official navy correspondence, archival information from universities, and newspaper articles of the period to reconstruct the recruitment, training, duty assignments, and postwar careers of these women.
With limited information, an effort has also been made to document the training of civilian women in the cadet program, and to estimate the number of women who served as forecasters in foreign countries during the war. The status of women in meteorology prior to the United States' entry into the war is examined as a backdrop to the study. Principal results of the study are as follows:
During February and March 1988, a limited field experiment was conducted over the Gulf of Mexico to gather data on two phenomena: air mass modification over the Loop Current, and return flow characteristics of modified polar air returning to the southern shores of the United States. Six-hourly radiosondes, special Cross- Chain LORAN (Long-Range Aid to Navigation) Atmospheric Sounding System (CLASS) soundings, and three P-3 flights including dropwindsondes and Airborne Expendable Bathythermograph (AXBT) measurements were taken. The experiment objectives and the data are described.
During February and March 1988, a limited field experiment was conducted over the Gulf of Mexico to gather data on two phenomena: air mass modification over the Loop Current, and return flow characteristics of modified polar air returning to the southern shores of the United States. Six-hourly radiosondes, special Cross- Chain LORAN (Long-Range Aid to Navigation) Atmospheric Sounding System (CLASS) soundings, and three P-3 flights including dropwindsondes and Airborne Expendable Bathythermograph (AXBT) measurements were taken. The experiment objectives and the data are described.
A historical review of research on sea fog is presented. The period of interest is essentially the twentieth century, beginning with the celebrated work of G. I. Taylor in the aftermath of the Titanic tragedy. It has been argued that relative maxima in fog frequency over the North Atlantic (including the British Isles and the Grand Banks of Newfoundland) and the North Pacific (including the U.S. West Coast) has led to major contributions by scientists in England and the United States. The early work (pre-World War II) tended to be phenomenological—that is, conceptual with broad inference from statistical summaries. Yet, this early work laid the foundation for the numerical modeling that came with the advent of computers in the postwar period. The subtleties associated with sea fog formation and maintenance are explored by analyzing some of the results from the numerical simulations. The essay ends with a speculative view on our prospects for a more complete understanding of sea fog in light of the earlier contributions.
A historical review of research on sea fog is presented. The period of interest is essentially the twentieth century, beginning with the celebrated work of G. I. Taylor in the aftermath of the Titanic tragedy. It has been argued that relative maxima in fog frequency over the North Atlantic (including the British Isles and the Grand Banks of Newfoundland) and the North Pacific (including the U.S. West Coast) has led to major contributions by scientists in England and the United States. The early work (pre-World War II) tended to be phenomenological—that is, conceptual with broad inference from statistical summaries. Yet, this early work laid the foundation for the numerical modeling that came with the advent of computers in the postwar period. The subtleties associated with sea fog formation and maintenance are explored by analyzing some of the results from the numerical simulations. The essay ends with a speculative view on our prospects for a more complete understanding of sea fog in light of the earlier contributions.
Abstract
The main field activities of the Coordinated Airborne Studies in the Tropics (CAST) campaign took place in the west Pacific during January–February 2014. The field campaign was based in Guam (13.5°N, 144.8°E), using the U.K. Facility for Airborne Atmospheric Measurements (FAAM) BAe-146 atmospheric research aircraft, and was coordinated with the Airborne Tropical Tropopause Experiment (ATTREX) project with an unmanned Global Hawk and the Convective Transport of Active Species in the Tropics (CONTRAST) campaign with a Gulfstream V aircraft. Together, the three aircraft were able to make detailed measurements of atmospheric structure and composition from the ocean surface to 20 km. These measurements are providing new information about the processes influencing halogen and ozone levels in the tropical west Pacific, as well as the importance of trace-gas transport in convection for the upper troposphere and stratosphere. The FAAM aircraft made a total of 25 flights in the region between 1°S and 14°N and 130° and 155°E. It was used to sample at altitudes below 8 km, with much of the time spent in the marine boundary layer. It measured a range of chemical species and sampled extensively within the region of main inflow into the strong west Pacific convection. The CAST team also made ground-based measurements of a number of species (including daily ozonesondes) at the Atmospheric Radiation Measurement Program site on Manus Island, Papua New Guinea (2.1°S, 147.4°E). This article presents an overview of the CAST project, focusing on the design and operation of the west Pacific experiment. It additionally discusses some new developments in CAST, including flights of new instruments on board the Global Hawk in February–March 2015.
Abstract
The main field activities of the Coordinated Airborne Studies in the Tropics (CAST) campaign took place in the west Pacific during January–February 2014. The field campaign was based in Guam (13.5°N, 144.8°E), using the U.K. Facility for Airborne Atmospheric Measurements (FAAM) BAe-146 atmospheric research aircraft, and was coordinated with the Airborne Tropical Tropopause Experiment (ATTREX) project with an unmanned Global Hawk and the Convective Transport of Active Species in the Tropics (CONTRAST) campaign with a Gulfstream V aircraft. Together, the three aircraft were able to make detailed measurements of atmospheric structure and composition from the ocean surface to 20 km. These measurements are providing new information about the processes influencing halogen and ozone levels in the tropical west Pacific, as well as the importance of trace-gas transport in convection for the upper troposphere and stratosphere. The FAAM aircraft made a total of 25 flights in the region between 1°S and 14°N and 130° and 155°E. It was used to sample at altitudes below 8 km, with much of the time spent in the marine boundary layer. It measured a range of chemical species and sampled extensively within the region of main inflow into the strong west Pacific convection. The CAST team also made ground-based measurements of a number of species (including daily ozonesondes) at the Atmospheric Radiation Measurement Program site on Manus Island, Papua New Guinea (2.1°S, 147.4°E). This article presents an overview of the CAST project, focusing on the design and operation of the west Pacific experiment. It additionally discusses some new developments in CAST, including flights of new instruments on board the Global Hawk in February–March 2015.
