You are here

Characteristics of Decaying Storms during Lightning Cessation at Kennedy Space Center and Cape Canaveral Air Force Station

Title: Characteristics of Decaying Storms during Lightning Cessation at Kennedy Space Center and Cape Canaveral Air Force Station.
121 views
24 downloads
Name(s): Anderson, Holly Alison, author
Fuelberg, Henry E., professor directing thesis
Ruscher, Paul H., committee member
Hart, Robert E., committee member
Department of Earth, Ocean and Atmospheric Sciences, degree granting department
Florida State University, degree granting institution
Type of Resource: text
Genre: Text
Issuance: monographic
Date Issued: 2010
Publisher: Florida State University
Place of Publication: Tallahassee, Florida
Physical Form: computer
online resource
Extent: 1 online resource
Language(s): English
Abstract/Description: Improved knowledge of thunderstorm behavior near the end of its lifecycle is essential to improving the prediction of lightning cessation. This study documents the characteristics of decaying storms near the end of their lightning activity at Kennedy Space Center (KSC) and Cape Canaveral Air Force Station (CCAFS). Total lightning data were obtained by combining information from the Lightning Detection and Ranging (LDAR) network with the Cloud-to-Ground-Surveillance System (CGLSS) and the National Lightning Detection Network (NLDN). The lightning data were used in conjunction with WSR-88D radar data and Rapid Update Cycle (RUC) model analyses. The study focuses on a dataset of 116 isolated unicellular and multicellular storms during the warm-seasons (May-September) of 2000-2005. Twenty of the 116 storms were tracked through lightning cessation using the K-Means storm clustering and tracking algorithm within the Warning Decision Support System – Integrated Information (WDSS-II). This tracking yielded time-series of radar-derived, RUC-derived, and lightning parameters. Flash characteristics of the 116 storms showed trends during storm growth and dissipation; however, none exhibited clear relationships with the final flash. Although most storms experienced gradually decaying flash rates until cessation, two other cessation behaviors also were observed, making flash activity an unreliable indicator of cessation. Trends in composite reflectivity, reflectivity at three temperatures crucial to storm electrification (i.e., 0°C, -10°C, -20°C), storm thickness of 30 dBZ above -10°C, and vertical gradients of reflectivity were analyzed for 20 storms during the 8 min period prior to cessation to determine if any indicated imminent cessation. Results showed substantial variability in the decaying storms. Although these parameters decreased in most storms during the 8 min period, some increased. Distributions of the parameters at the last flash also were considered, but no clearly preferred value was evident at the last flash. Neither the inversion of lightning initiation criteria (e.g., 40 dBZ at -10°C) nor the descent of 45 dBZ below -10°C were found to be a useful indicator of cessation. Previously-documented lightning "bubbles" of LDAR sources were observed and were consistent with pulses in the intensifying updrafts. The last lightning "bubble" signatures were found to precede lightning cessation by ~35 min.
Identifier: FSU_migr_etd-0197 (IID)
Submitted Note: A Thesis submitted to the Department of Meteorology in partial fulfillment of the requirements for the degree of Master of Science.
Degree Awarded: Degree Awarded: Spring Semester, 2010.
Date of Defense: Date of Defense: December 9, 2009.
Keywords: Lightning Cessation, Total Lightning, LDAR, WDSS-II, NASA, Forcasting
Bibliography Note: Includes bibliographical references.
Advisory committee: Henry E. Fuelberg, Professor Directing Thesis; Paul H. Ruscher, Committee Member; Robert E. Hart, Committee Member.
Subject(s): Meteorology
Persistent Link to This Record: http://purl.flvc.org/fsu/fd/FSU_migr_etd-0197
Owner Institution: FSU

Choose the citation style.
Anderson, H. A. (2010). Characteristics of Decaying Storms during Lightning Cessation at Kennedy Space Center and Cape Canaveral Air Force Station. Retrieved from http://purl.flvc.org/fsu/fd/FSU_migr_etd-0197