Collaborative Research: The Kinematics, Microphysics and Dynamics of Long-fetch Lake-effect Systems in Ontario Winter Lake-effect Systems (OWLeS)

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This award is one key segment of a larger effort centered on the Ontario Winter (OW) Lake-effect Systems (LeS) field project, to be conducted December 2013-January 2014. OWLeS will focus on two complementary lines of research, each tracing to a preferred wind regime over the U.S. Great lakes region and corresponding distinct mesoscale mode of winter storm organization. Activities led by this group will focus on so-called "long-fetch" storm events, for which low-level winds are aligned approximately parallel to Lake Ontario's long axis. Observational assets to be employed during OWLeS include the University of Wyoming King Air instrumented aircraft, the CSWR Doppler on Wheels (DOW) mobile radars, multiple mobile rawinsounding systems, the Millersville University Profiling System, the UAH Mobile Integrated Profiling System, and a variety of other deployable surface measurement systems. These researchers contend that predictions of the amounts and inland extent of LeS snowfall remain poor, due in part to fine-scale variations in upwind planetary boundary layer structure and poor representation of cloud microphysical, dynamical, and surface processes. To address these shortcomings, the intellectual merits of this research will derive from improved understanding of: 1) How long-fetch LeS intensify and evolve downwind of the lake, where prolonged heavy snowfall rates are particularly impactful; 2) how cloud and dynamical processes may contribute to cloud electrification and to lightning, as occasionally observed in long-fetch LeS heavy precipitation cells; and 3) how dual-polarimetric (and in select regions, dual-Doppler) radar measurements at X- and S-band wavelengths as utilized by mobile-DOW and operational National Weather Service WSR-88D radars, respectively, may reveal detailed precipitation processes in LeS. Through detailed comparisons with in-situ aircraft measurements, evaluations dual-polarimetric particle identification and quantitative precipitation estimate (QPE) algorithms will extend the utility of remote-sensing observations in this unique cool-season environment.Broader impacts will include experience infield campaign planning, hands-on data collection and data analysis for a notably large number of undergraduate as well as graduate students. A desirable mix of junior and senior principal investigators will facilitate exchange of established and complex project design and observing methodologies, and foster improved field observing techniques tailored to severe winter weather conditions. Outreach efforts will extend to K-12 students and college students enrolled at nearby institutes of higher learning. Given the significant impacts of lake effect snowfall on public safety and economic activity along the populous shores of the U.S. Great Lakes, improved understanding of lake-effect systems should foster refined models and forecasting techniques that will address a longer-term societal need.