Lester Machta: Difference between revisions
No edit summary |
No edit summary |
||
Line 8: | Line 8: | ||
== Career == |
== Career == |
||
In 1948 [[Harry Wexler]] hired Machta to join the United States [[National Weather Service|Weather Bureau]] as Chief of the Special Projects Section, which later became the Air Resources Laboratory. The initial purpose of the Special Projects Section was to study nuclear activities from a meteorological and environmental perspective. Even before the Soviet Union developed its first atomic bomb, the US made preparations to detect and analyze nuclear testing<ref>{{cite web |last1=University Corporation for Atmospheric Research |title=Interview of Lester Machta |url=https://opensky.ucar.edu/islandora/object/archives%3A8234 |website=Tape Recorded Interview Project |accessdate=7 December 2019}}</ref> and when the first Soviet bomb was detonated in 1949 there was a concerted effort to determine its yield, location, and the subsequent transport of radioactive materials<ref>{{cite journal |last1=Machta |first1=L. |title=Finding the |
In 1948 [[Harry Wexler]] hired Machta to join the United States [[National Weather Service|Weather Bureau]] as Chief of the Special Projects Section, which later became the Air Resources Laboratory. The initial purpose of the Special Projects Section was to study nuclear activities from a meteorological and environmental perspective. Even before the Soviet Union developed its first atomic bomb, the US made preparations to detect and analyze nuclear testing<ref>{{cite web |last1=University Corporation for Atmospheric Research |title=Interview of Lester Machta |url=https://opensky.ucar.edu/islandora/object/archives%3A8234 |website=Tape Recorded Interview Project |accessdate=7 December 2019}}</ref> and when the first Soviet bomb was detonated in 1949 there was a concerted effort to determine its yield, location, and the subsequent transport of radioactive materials<ref>{{cite journal |last1=Machta |first1=L. |title=Finding the Site of the First Soviet Nuclear Test in 1949 |journal=Bulletin of the American Meteorological Society |date=1992 |volume=73 |page=1797-1806}}</ref>. Under Machta’s direction, the Special Projects Section assisted in weapons testing at the [[Nevada Test Site|Nevada]] and [[Nuclear testing at Bikini Atoll|Bikini]] test sites by providing predictions of near-term downwind [[nuclear fallout]] from the explosions. |
||
Machta also investigated long-term fallout resulting from radioactive materials injected into the stratosphere by nuclear testing. He realized that radioactive materials in the atmosphere could also serve as useful tracers to understand atmospheric circulation. The Atomic Energy Commission initially minimized the risk from long-term fallout using a simple model developed by [[Willard Libby]] that presumed fallout would be well-mixed in the stratosphere, would reach the ground over a period of 10 years, and be uniformly distributed over the surface of the Earth. Using the more realistic [[Brewer–Dobson circulation|Brewer-Dobson model]] of atmospheric circulation, Machta showed that radioactive fallout would reach the ground sooner and be disproportionately concentrated in the populated mid-latitudes, and thus produce much more substantial health risks<ref>{{cite book |last1=Higuchi |first1=T. |title=Radioactive Fallout, the Politics of Risk, and the Making of a Global Environmental Crisis, 1954-1963 |
Machta also investigated long-term fallout resulting from radioactive materials injected into the stratosphere by nuclear testing. He realized that radioactive materials in the atmosphere could also serve as useful tracers to understand atmospheric circulation. The Atomic Energy Commission initially minimized the risk from long-term fallout using a simple model developed by [[Willard Libby]] that presumed fallout would be well-mixed in the stratosphere, would reach the ground over a period of 10 years, and be uniformly distributed over the surface of the Earth. Using the more realistic [[Brewer–Dobson circulation|Brewer-Dobson model]] of atmospheric circulation, Machta showed that radioactive fallout would reach the ground sooner and be disproportionately concentrated in the populated mid-latitudes, and thus produce much more substantial health risks<ref>{{cite book |last1=Higuchi |first1=T. |title=Radioactive Fallout, the Politics of Risk, and the Making of a Global Environmental Crisis, 1954-1963 |type=Ph.D. Thesis |date=2011 |publisher=Georgetown University |location=Washington, DC}}</ref>. He presented these conclusions in Congressional testimony<ref>{{cite book |last1=Special Subcommittee on Radiation of the Joint Committee on Atomic Energy, U.S. Congress |title=The Nature of Radioactive Fallout and Its Effects on Man |date=June 4-7, 1957 |publisher=Government Printing Office |location=Washington, DC |pages=141-169}}</ref>, contributing significantly to the scientific rationale for ending above-ground nuclear testing<ref>{{cite book |last1=Jessee |first1=E. J. |editor1-last=Fleming |chapter= A Heightened Controversy: Nuclear Weapons Testing, Radioactive Tracers and the Dynamic Stratosphere|editor1-first=J. R. |editor2-last=Johnson |editor2-first=A. |title=Toxic Airs: Body, Place, Planet in Historical Perspective |date=2014 |publisher=University of Pittsburgh Press |location=Pittsburgh}}</ref>. Machta participated in the 1958 Experts’ Conference in Geneva [zoppo] that lead to the 1963 [[Partial Nuclear Test Ban Treaty]]. |
||
After Wexler’s death, Machta played a crucial role supporting the work of [[Charles David Keeling|David Keeling’s]] measurements of[[Carbon dioxide in Earth’s atmosphere|atmospheric carbon dioxide]] at the [[Mauna Loa Observatory|Mauna Loa]] and South Pole Observatories [aip]. In 1971 Machta played a key role in establishing the Geophysical Monitoring for Climate Change program [mendonca] (now in the NOAA Climate Monitoring and Diagnostics Laboratory) with additional atmospheric observatories. |
After Wexler’s death, Machta played a crucial role supporting the work of [[Charles David Keeling|David Keeling’s]] measurements of[[Carbon dioxide in Earth’s atmosphere|atmospheric carbon dioxide]] at the [[Mauna Loa Observatory|Mauna Loa]] and South Pole Observatories [aip]. In 1971 Machta played a key role in establishing the Geophysical Monitoring for Climate Change program [mendonca] (now in the NOAA Climate Monitoring and Diagnostics Laboratory) with additional atmospheric observatories. |
Revision as of 18:38, 7 December 2019
This article, Lester Machta, has recently been created via the Articles for creation process. Please check to see if the reviewer has accidentally left this template after accepting the draft and take appropriate action as necessary.
Reviewer tools: Inform author |
Lester Machta (February 17, 1919 - August 31, 2001) was an American meteorologst, the first director of the Air Resources Laboratory (ARL) of the National Oceanic and Atmospheric Administration.
Life
Lester Machta was born in Brooklyn, New York, the son of Jewish immigrants from Russia. He attended City College and Brooklyn College, graduating in 1939. After a year of graduate study Machta entered military service as a meteorology instructor training pilots for the Army and Army Air Corps. He received an M.A. in Meteorology from New York University in 1946 and a Sc.D. in Meteorology from M.I.T. in 1948. He married Phyllis Margaretten in 1948 and they had two children. [1]
Career
In 1948 Harry Wexler hired Machta to join the United States Weather Bureau as Chief of the Special Projects Section, which later became the Air Resources Laboratory. The initial purpose of the Special Projects Section was to study nuclear activities from a meteorological and environmental perspective. Even before the Soviet Union developed its first atomic bomb, the US made preparations to detect and analyze nuclear testing[2] and when the first Soviet bomb was detonated in 1949 there was a concerted effort to determine its yield, location, and the subsequent transport of radioactive materials[3]. Under Machta’s direction, the Special Projects Section assisted in weapons testing at the Nevada and Bikini test sites by providing predictions of near-term downwind nuclear fallout from the explosions.
Machta also investigated long-term fallout resulting from radioactive materials injected into the stratosphere by nuclear testing. He realized that radioactive materials in the atmosphere could also serve as useful tracers to understand atmospheric circulation. The Atomic Energy Commission initially minimized the risk from long-term fallout using a simple model developed by Willard Libby that presumed fallout would be well-mixed in the stratosphere, would reach the ground over a period of 10 years, and be uniformly distributed over the surface of the Earth. Using the more realistic Brewer-Dobson model of atmospheric circulation, Machta showed that radioactive fallout would reach the ground sooner and be disproportionately concentrated in the populated mid-latitudes, and thus produce much more substantial health risks[4]. He presented these conclusions in Congressional testimony[5], contributing significantly to the scientific rationale for ending above-ground nuclear testing[6]. Machta participated in the 1958 Experts’ Conference in Geneva [zoppo] that lead to the 1963 Partial Nuclear Test Ban Treaty.
After Wexler’s death, Machta played a crucial role supporting the work of David Keeling’s measurements ofatmospheric carbon dioxide at the Mauna Loa and South Pole Observatories [aip]. In 1971 Machta played a key role in establishing the Geophysical Monitoring for Climate Change program [mendonca] (now in the NOAA Climate Monitoring and Diagnostics Laboratory) with additional atmospheric observatories.
Machta was also an expert on stratospheric ozone and oversaw the United States network of Dobson ozone spectrophotometers. Machta served as a member for the International Ozone Commission from 1964-1971 [io3c]. At a conference in 1972, Machta alerted F. Sherwood Rowland to James Lovelock’s measurements showing that chloroflourocarbons (CFCs) are present in the stratosphere, sparking the research that led to the discovery that CFCs deplete the ozone layer[rowland]. Machta also worked on transport of air pollution and acid rain [seidel] . He was the U.S. co-chair of the International Air Quality Advisory Board of the International Joint Commission that addressed cross-boundary air pollution issues affecting the United States and Canada, and he was the NOAA representative to the National Acid Precipitation Assessment Program.
Honors
- Department of Commerce Medal for Exceptional Service (1957,1985)
- Fellow of the American Association for the Advancement of Science (1980)
- Fellow of the American Geophysical Union (1984)
- Fellow of the American Meteorological Society
- The Cleveland Abbe Award for Distinguished Service to Atmospheric Sciences (1974)
- NOAA Administrator’s Award (1995)
References
- ^ American Meteorological Society. "Lester Machta". AMS Online journals, necrologies. Retrieved 7 December 2019.
- ^ University Corporation for Atmospheric Research. "Interview of Lester Machta". Tape Recorded Interview Project. Retrieved 7 December 2019.
- ^ Machta, L. (1992). "Finding the Site of the First Soviet Nuclear Test in 1949". Bulletin of the American Meteorological Society. 73: 1797-1806.
- ^ Higuchi, T. (2011). Radioactive Fallout, the Politics of Risk, and the Making of a Global Environmental Crisis, 1954-1963 (Ph.D. Thesis). Washington, DC: Georgetown University.
- ^ Special Subcommittee on Radiation of the Joint Committee on Atomic Energy, U.S. Congress (June 4–7, 1957). The Nature of Radioactive Fallout and Its Effects on Man. Washington, DC: Government Printing Office. pp. 141–169.
{{cite book}}
: CS1 maint: date format (link) - ^ Jessee, E. J. (2014). "A Heightened Controversy: Nuclear Weapons Testing, Radioactive Tracers and the Dynamic Stratosphere". In Fleming, J. R.; Johnson, A. (eds.). Toxic Airs: Body, Place, Planet in Historical Perspective. Pittsburgh: University of Pittsburgh Press.