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- All Subjects: Dust storms
- Creators: Cerveny, Randall S.
Description
Several short term exogenic forcings affecting Earth's climate are but recently identified. Lunar nutation periodicity has implications for numerical meteorological prediction. Abrupt shifts in solar wind bulk velocity, particle density, and polarity exhibit correlation with terrestrial hemispheric vorticity changes, cyclonic strengthening and the intensification of baroclinic disturbances. Galactic Cosmic ray induced tropospheric ionization modifies cloud microphysics, and modulates the global electric circuit. This dissertation is constructed around three research questions: (1): What are the biweekly declination effects of lunar gravitation upon the troposphere? (2): How do United States severe weather reports correlate with heliospheric current sheet crossings? and (3): How does cloud cover spatially and temporally vary with galactic cosmic rays? Study 1 findings show spatial consistency concerning lunar declination extremes upon Rossby longwaves. Due to the influence of Rossby longwaves on synoptic scale circulation, our results could theoretically extend numerical meteorological forecasting. Study 2 results indicate a preference for violent tornadoes to occur prior to a HCS crossing. Violent tornadoes (EF3+) are 10% more probable to occur near, and 4% less probable immediately after a HCS crossing. The distribution of hail and damaging wind reports do not mirror this pattern. Polarity is critical for the effect. Study 3 results confirm anticorrelation between solar flux and low-level marine-layer cloud cover, but indicate substantial regional variability between cloud cover altitude and GCRs. Ultimately, this dissertation serves to extend short term meteorological forecasting, enhance climatological modeling and through analysis of severe violent weather and heliospheric events, protect property and save lives.
ContributorsKrahenbuhl, Dan (Author) / Cerveny, Randall S. (Thesis advisor) / Dorn, Ron (Committee member) / Shaffer, John (Committee member) / Arizona State University (Publisher)
Created2013
Description
Dust storms have far-reaching human and economic impacts; spreading disease, raspatory and cardiovascular disruption, destruction of property and crops, and death. Understanding of this phenomenon is can help with operational and academic endeavors and alleviate some of these impacts. To accomplish this goal, this dissertation poses a central question: Do dust storms have discreet geographic and temporal characteristics that can aid academic and operational analysis of these storms? To answer this question three case studies were undertaken. The first study constructed an archive of 549 dust rain events across Europe to determine a seasonal pattern. It was discovered that the largest number of events occurred in the Spring season (MAM). Then three individual events across Europe were examined to highlight the synoptic events that control these dust rains. Each event can be closely tied to the movement of the migratory Rossby waves and linked to Saharan dust from North Africa. The second study was a construction of Central Sonoran Desert dust storms from 2009 to 2022 tied to the NAM. HYSPLIT back-trajectories linked the strongest events to source regions mainly from the Southwest along the Gila River from the Gulf of California. As the storms weaken in intensity they drift to the South and Southeast traveling along the Santa Cruz River and its tributaries. The third study was a case study of three large events in the Central Sonoran Desert along the Gila River. This study examines the effects of the local topography, specifically the stand-alone mountain complexes that can block or funnel dust as it moves through the Gila River Valley. In each instance the South Mountain Complex and the Sierra Estrella served as a dust shield containing the highest dust concentrations to the south side of the Gila River Valley. This dissertation has analyzed several of the different elements of dust storms. These elements include the synoptic patterns that drive dust storms, the source regions of dust storms, and the ground level topography that can control their movement. Fundamentally, these findings can enhance our academic understanding of dust storms as well as our operational ability to forecast.
ContributorsWhite, Joshua Randolph (Author) / Cerveny, Randall S. (Thesis advisor) / Balling Jr., Robert C. (Committee member) / Brazel, Anthony (Committee member) / Arizona State University (Publisher)
Created2024