Comparison of AI and NWP models in operational severe weather
forecasting: A Study on Tropical Cyclone Predictions
Abstract
Data-driven artificial intelligence (AI)-based weather prediction (AIWP)
models have demonstrated significant potential in weather forecasts,
facilitating paradigm shift of prediction from a deductive to an
inductive inference. However, this shift raises concerns regarding the
performance of the AIWP models in severe weather forecasting. Tropical
cyclones (TCs) are one of the most typical cases of severe weather
forecasting. In this study, we compare forecasts of Western Pacific TCs
in 2023 produced by the AIWP model, Pangu-Weather, with those generated
by numerical weather prediction (NWP) models, specifically the European
Centre for Medium-Range Weather Forecasts (ECMWF) and the National
Centers for Environmental Prediction (NCEP), in the operational context.
We analyze the impact of different initial conditions on the AIWP model
Pangu-Weather, in TC forecasting. Our analysis includes statistical
evaluation of forecast skills related to TC activity, track, intensity,
and a case study on the physical structure of TCs. The Pangu-Weather
model exhibits superior forecast skills compared to the NWP model
regarding TC tracks and environmental variables within TC activity
domains, particularly at longer leading times. However, the overly
smooth forecasts from Pangu-Weather lead to significant underestimations
of intensity and a weakened dynamic-thermodynamic structure of TCs.
Additionally, Pangu-Weather shows reduced sensitivity to initial
conditions concerning TC structure and intensity, potentially
attributable to the limitations of the training dataset and deep
learning model employed. Enhancing the application of higher-quality
initial conditions and the exploring hybrid models that integrate
physical processes with data-driven methods could significantly improve
the effectiveness of AIWP models in severe weather forecasting.