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https://hdl.handle.net/10217/200693
This digital collection includes publications by faculty, researchers, and/or students in the Department of Atmospheric Science.

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Browsing Publications by Subject "Atmospheric circulation"

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    Causes and effects of atmospheric interannual variability: progress report to National Science Foundation
    (Colorado State University. Libraries, 1977-06) Reiter, Elmar R., author; Department of Atmospheric Science, Colorado State University, publisher
    During the present grant period we examined in some detail the 24-day vacillation in the atmospheric energy cycle. We arrived at the conclusion that this cycle is tied to baroclinic instabilities and to the amplification of cyclonic disturbances upon which feed the planetary wave modes. We also examined cases of sudden stratospheric warming. They are generally characterized by prolonged decreases in hemispheric zonal available potential energy, by the development of a blocking ridge over the Gulf of Alaska and by a tendency towards below-normal temperatures over the Eastern United States. A feasibility study of hemispheric monthly precipitation anomalies revealed that large anomalies, indeed, exist simultaneously and with same sign over the continents of the northern hemisphere. From this conclusion the importance of the hydrological cycle in atmospheric variability studies has to be emphasized again. Another source of atmospheric interannual variability has been identified in the sensible and latent heat transfers between ocean and atmosphere. The 24-day vacillation appears to be influenced by these heat transfers, especially in regions with large sea surface temperature (SST) anomalies. The SST anomalies in the North Pacific between 40 and 50°N appear to be caused by fluctuations in the water transport around the Pacific gyro. This transport, in turn, seems to respond to long-term and large-scale fluctuations in the v-component of the trade winds in both hemispheres. Such fluctuations also appear to influence the global mean annual temperature, perhaps due to variations in the release of latent heat within the intertropical convergence zone.
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    ItemOpen Access
    On the variability of hemispheric scale energy parameters
    (Colorado State University. Libraries, 1975) McGuirk, James P., author; Reiter, Elmar R., author; Barbieri, Ann M., author; Colorado State University, publisher
    Hemispheric scale energy parameters have been computed and their variability on an annual time scale and a scale of a few weeks is identified and discussed. Based on data for 15 winter seasons, the annual variability of available potential energy is linked to fluctuations of elements of the general circulation, such as the jet streams. This link establishes a relationship between simply computed hemispheric scale parameters and regional weather conditions affecting man's economic wellbeing. Daily statistics on three winter seasons of hemispheric energy modes have been analyzed with the ultimate goal of understanding and reproducing the behavior of the hemispheric energy cycle. Two phenomena are discussed: (1) A strong 22-26 day cycle in the energy modes which may be linked to synoptic scale systems and the atmospheric index cycle; and (2) A large midwinter "dip" in zonal available potential energy which is tentatively linked to a possible movement of the Hadley cell. This "dip" is shown to have a profound effect on the meridional temperature gradient, particularly in midlatitudes.