The Massive Space and Time Scale of Atmospheric Processes

    The Massive Space and Time Scale of Atmospheric Processes

     

     

    The Massive Space and Time Scale of Atmospheric Processes that Create Localized Extreme Heat Bursts, Dry Lightning, Wildland Fires, and Debris Flows in the Western U.S.

    Mike Kaplan, Research Professor, Division of Atmospheric Sciences, Desert Research Institute, Reno, Nevada. michael.kaplan@dri.edu

    Co-authors: Benjamin J. Hatchett, Nicholas J. Nauslar, Nina S. Oakley, Jeffrey S. Tilley, and Craig M. Smith

    During the warm season local terrain and ecological disturbances over the intermountain western U.S. are often the result of cascading events that have their origins in atmospheric circulations that span thousands of kilometers in space and as long as a week or more in time. Natural and/or manmade climate forcing establishes these circulations as a downscale dissipative signal in the atmosphere. Thus climate organizes shorter period spatial and temporal weather that targets local complex terrain. Planetary wave breaking (PWB) over the complex terrain of the western U.S. PWB often organizes a cascading group of finer scale circulations and linked natural disasters. PWB occurs over scales ~2500-5000 km and 3-5 days when a disturbance in the jet stream collides with downstream blocking flow. Dry lightning often is the result of PWB during the warm season over the elevated western plateaus triggering wildland fires that produce burn scars resulting in subsequent flash flooding and debris flows days, months, or years later.

    Kaplan is a Research Professor in the Division of Atmospheric Sciences at the Desert Research Institute in Reno, Nevada. He also teaches undergraduate and graduate courses in atmospheric dynamics, weather forecasting, and atmospheric numerical modeling in the Atmospheric Sciences Graduate and Undergraduate Programs at the University of Nevada Reno where he advises numerous graduate students. His interests are in synoptic, meso, and multi-scale dynamical meteorology. He has 50 years of experience in this and related problems. During his career he has performed research as an Air Force Weather Officer, small business owner, private consultant, NASA contractor, and Research Professor at North Carolina State University and the University of Nevada Reno. Presently, his main research focus is on multi-scale dynamics, forecasting, and modeling of extreme western weather including heat bursts, damaging wind systems, floods, snowstorms, fire meteorology, debris flows, and tornadic convection. He is an American Meteorological Society Certified Consulting Meteorologist.