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Lester Machta

Abstract

In this paper a new wave solution of the vorticity equation for plane nondivergent horizontal motion in the atmosphere is presented. The treatment differs from that given previously by Rossby in that the troughs and ridges do not lie along meridians but may possess a tilt. Owing to this feature the resulting waves produce a meridional transport of momentum and energy.

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Lester Machta

Efforts by the U.S. government to detect the first Soviet atomic test began at least as early as 1946. Interception of radioactive debris from the first test was made by the Air Weather Service B-29 weather reconnaissance aircraft, which was equipped to filter particles from the air, on 3 September 1949 at 500 mb east of Kamchatka. The U.S. Weather Bureau was charged with trying to find the likely testing grounds from this first interception and a few later ones. The test site was found using backward air trajectories from the radioactivity detection line and a time of detonation to determine where to stop the backward trajectories. The explosion time, with large error bars, was obtained from radiochemical analysis of the particulate debris. In 1949, best time was estimated to be about 1500 UTC on 27 August. This was then combined with 500-mb backward trajectories to place the likely test site, incorrectly, near the northern part of the Caspian Sea. The uncertainties in the test time and in the calculated trajectories allowed the test site to be possible over a much larger region.

Subsequently, the real explosion time was found to be about 0100 UTC 29 August, placing the most likely test site, from the 1949 Weather Bureau trajectories, just south of Lake Balkash. The true test site has also been revealed to be the Khazakh Test Site, and is 250 to 275 miles north of this latter calculated position. The percentage error between the calculated and correct source position relative to the trajectory distance is about 5%. This value, 5%, is much smaller than the more typical 20% errors found by other studies.

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Lester Machta

The geophysical observatory at Mauna Loa was established as part of the U. S. contribution to the International Geophysical Year in 1957 largely at the instigation of the late Dr. Harry Wexler. Its record of carbon dioxide concentration in clean air is unique.

There is much concern in recent years lest the growing pace of man's activities affect the weather or climate on a large scale. Among the prime constituents of the air which may cause such changes are carbon dioxide and dust. Both of these elements are monitored at Mauna Loa. The upward trend of carbon dioxide superimposed on a seasonal variation confirms the contribution from man's combustion of fossil fuels but the normal incidence solar radiation measurements exhibit no long term trend other than that due to volcanic activity beginning with the eruption at Mt. Agung in 1963. The records of atmospheric carbon dioxide and normal incidence solar radiation of several other stations confirm the carbon dioxide trends but temperate latitude stations show no decrease in normal incidence solar radiation.

The ultimate objective of monitoring is the prediction of future concentrations so that their impact on the environment can alert society for a need to control its activity if necessary. The future prediction of atmospheric carbon dioxide based on a simple atmosphere-ocean-biosphere model calibrated by bomb carbon-14 leads to predictions of about 380 ppm in the year 2000 but with many reservations.

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Lester Machta
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Lester Machta
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Lester Machta

Abstract

No Abstract Available.

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