7 Oct (CLIM) - Nedza, UFS Tropical Cyclones

Speaker: Dr. Douglas Nedza, George Mason University

Title: Evaluating Seasonal Forecasts of Tropical Cyclone Activity using Experimental UFS Prototypes

Time: Wed, 7 Oct, 1:30-2:30 pm 

Location: Exploratory Hall, Room L111 or via Zoom (for Zoom link, email xdu5@gmu.edu) 

ABSTRACT: Many agencies issue seasonal outlooks of tropical cyclone (TC) activity informing planning activities.  NOAA is in the process of developing a next-generation dynamical forecast system, the Unified Forecast System (UFS).  As part of this development process, ensembles of reforecasts are produced using the experimental prototypes of UFS to serve as a test-bed to evaluate seasonal forecast skill. Here, we evaluate UFS prototypes Beta1.0, P8, and HR3, in forecasting western North Pacific (WNP) and North Atlantic (NA) seasonal TC activity in April and May initialized reforecasts.  Reforecast TC events are identified using the TempestExtremes event tracking algorithm based on characteristic features of TCs, such as local sea level pressure, temperature, and winds.  Dynamical forecasts of seasonal TC event numbers and accumulated cyclone energy (ACE) are produced by aggregating the identified TC events.  Reforecast variations of TC activity are generally skillful over the reforecast period, although correlations values depend on the TC identification criterion, oceanic basin, and forecasted TC metric.   Biases in seasonal TC activity are assessed and related to biases in the large-scale environment for each basin.