The Use of Potential Vorticity Diagnostics to Evaluate Differences Between Two Datasets: February 14-15, 2003
Martin A. Baxter, Ph.D.
Central Michigan University
The use of potential vorticity (PV) as a large-scale diagnostic has been used within the research community for many years. Recent research has demonstrated the utility of using PV diagnostics to evaluate the impact of latent heat release within a model forecast. Through a technique known as piecewise PV inversion, the wind and height perturbations due to a given PV distribution can be calculated. For the February 14-15 2003 case in the Midwestern United States, this technique is used to isolate the flow resulting from PV in the low- to mid- levels, illustrating the influence any diabatically produced PV anomalies had on the large-scale flow. The differences in the PV structure and resulting perturbed flow are evaluated between a 48 hr WRF-ARW simulation and output from the North American Regional Reanalysis dataset valid for the same time. In addition, the utility and feasibility of the use of piecewise PV inversion in operational forecasting will be discussed.