Show simple item record

dc.contributor.advisorMartinelli, Jasonen_US
dc.contributor.authorLudwig, Stephanie L.en_US
dc.date.accessioned2010-05-18T22:53:37Z
dc.date.available2010-05-18T22:53:37Z
dc.date.issued2010-05-03en_US
dc.identifier.otherLudwig_creighton.edu_0339M_10011.pdf
dc.identifier.urihttp://hdl.handle.net/10504/6118
dc.description.abstractOn several significant tornado days, a distinct combination of near surface (< 1 km AGL) speed and directional shear has been noted in pre-tornadic vertical wind profiles. This combination consists of intense speed shear followed by intense directional shear between the surface and 1 km AGL, which appears as a sickle-shape on a hodograph. A composite sickle-shaped hodograph was constructed using several notable tornado outbreak days. The composite hodograph was used to examine the historical upper-air database for the 1995-2004 period in order to determine the relative frequency of the sickle-shape. Furthermore, the occurrence of the sickle-shape was related to severe weather documented within spatial and temporal proximity of the sounding site. Over the 10-year dataset, the sickle-shape was found to occur at most 4% of the time. It was also found that the sickle-shape occurs less than 0.5% of the time in the presence of minimally supportive kinematics and thermodynamics. On those days when the sickle-shape was accompanied by minimally supportive kinematics and thermodynamics (0-6 km AGL shear ≥ 20 m s-1 and CAPE ≥ 500 J kg-1), it was found that severe weather and tornadoes were more likely to be observed in proximity to the sounding site. The results show that the presence of the sickle-shaped hodograph and minimally supportive thermodynamics and kinematics is related to an increased likelihood of tornadic and significantly tornadic events.en_US
dc.language.isoen_USen_US
dc.publisherCreighton Universityen_US
dc.rightscopyright Stephanie L. Ludwigen_US
dc.titleThe Association of Strong Near-Surface Wind Shear Profiles with Enhanced Probabilities of Significant Severe Weather and Tornado Events.en_US
dc.typeThesis
dc.rights.holderStephanie L. Ludwigen_US
dc.publisher.locationOmaha, Nebraskaen_US
dc.contributor.cuauthorLudwig, Stephanie L.en_US
dc.embargo.terms2012-05-07
dc.degree.levelMS (Master of Science)en_US
dc.degree.disciplineAtmospheric Sciences (graduate program)en_US
dc.degree.nameM.S. Atmospheric Scienceen_US
dc.degree.grantorGraduate Schoolen_US
dc.degree.committeeMiller, Daniel J.en_US
dc.degree.committeeSchrage, Jon M.en_US
dc.degree.committeeZehnder, Joseph A.en_US


Files in this item

Thumbnail

This item appears in the following Collection(s)

Show simple item record