The role of diabatically generated potential vorticity in the North Atlantic stormtrack

It is known from case studies that diabatically generated potential vorticity (DPV) plays an important role in the development of individual extratropical cyclones. Here we investigate the systematic interaction between DPV and extratropical cyclones in the North Atlantic stormtrack. The Weather Research and Forecast (WRF) model is used to simulate ten winter seasons, and the DPV tendency is calculated from the model output. Regression analyses and PV inversions are used to quantify the effects of latent heat release on the structures of typical cyclones. Contributions of DPV to the stormtrack may be underestimated at GCM grid scales. To test this, simulations were run at coarse (120 km) and fine (20 km) resolutions. Diabatic processes are important for cyclone development and may also be important for the transports of heat, moisture, and momentum by the stormtrack.