Phys.org October 12, 2022
Researchers in China cycled and evaluated western North Pacific (WNP) typhoons of 2016 using Kalman filter (EnKF) combined with the Advanced Research Weather Research and Forecasting model (WRF). For all TC categories, the 6-h ensemble priors from the WRF/EnKF system had an appropriate amount of variance for TC tracks but had insufficient variance, they overestimated the intensity for weak storms but underestimated the intensity for strong storms. Comparison with the 5-d deterministic forecasts compared to the NCEP [US] and ECMWF [European] operational control forecasts showed that the WRF/EnKF forecasts generally had larger track errors than the NCEP and ECMWF forecasts for all TC categories as regional simulation cannot represent the large-scale environment better than the global simulation. The WRF/EnKF forecasts produced smaller intensity errors and biases than the NCEP and ECMWF forecasts for typhoons, but the opposite was true for tropical storms and severe tropical storms. The 5-d ensemble forecasts from the WRF/EnKF system for seven typhoon cases showed appropriate variance for TC track and intensity with short forecast lead times but had insufficient spread with long forecast lead times. According to the researchers the WRF/EnKF system provides better ensemble forecasts and higher predictability for TC intensity than the NCEP and ECMWF ensemble forecasts…read more. Open Access TECHNICAL ARTICLEÂ