The People Behind the PhDs 08: Stephen Bieda III – The clouds are forming. Lighting strikes 2-3
People behind the PhDs 08: Stephen Bieda III – Preview
Stephen Bieda III Bio
Dr. Stephen Bieda is the Science & Operations Officer (SOO) at National Weather Service Amarillo, TX. Dr. Bieda received his B.S. (2003), M.S. (2007) and Ph.D. (2012) from the University of Arizona in meteorology and climatology. In the capacity of NWS Amarillo SOO, he is the chief scientific advisor to the Meteorologist-in-Charge. In addition, Dr. Bieda oversees the science, research and operational programs of the office for purposes of protecting life and property from weather hazards in the Texas and Oklahoma Panhandles. Dr. Bieda has been an operational government meteorologist or scientist for 9 years, and serves on the American Meteorological Society (AMS) Board of Operational Government Meteorologists as well as the AMS Committee on Weather Analysis & Forecasting.
Abstract: The Relationship of Transient Upper-Level Troughs to Variability of the North American Monsoon System
Relationships between transient upper-tropospheric troughs and warm season convective activity over the southwest United States and northern Mexico are explored. Analysis of geopotential height and vorticity fields from the North American Regional Reanalysis and cloud-to-ground lightning data indicates that the passage of mobile inverted troughs (IVs) significantly enhances convection when it coincides with the peak diurnal cycle (1800–0900 UTC) over the North American monsoon (NAM) region. The preferred tracks of IVs during early summer are related to the dominant modes of Pacific sea surface temperature (SST) variability. When La Niña–like (El Niño–like) conditions prevail in the tropical Pacific and the eastern North Pacific has a horseshoe-shaped negative (positive) SST anomaly, IVs preferentially track farther north (south) and are slightly (typically one IV) more (less) numerous. These results point to the important role that synoptic-scale disturbances play in modulating the diurnal cycle of precipitation over the NAM region and the significant impact that the statistically supported low-frequency Pacific SST anomalies exert on the occurrence and track of these synoptic transients.
Music by Kate SC