Project Acronym: SWFTitle: Seasonal Weather ForecastAffiliation: harokopio university of athensPi: Petros KatsafadosResearch Field: earth system sciences
Temperature Seasonal Predictability of the WRF Model
by Varlas, G. and Katsafados, P. and Papadopoulos, A.
Abstract:
It is a common sense that there is no usable forecast skill at seasonal lead times due to the rapid drop-off of the predictability after a few days from the initialization of a simulation. However, there is some skill in predicting anomalies in the seasonal average of the weather such as anomalies of the persistent atmospheric patterns or even deviation from the climatology. In this study, the forecast skill on a seasonal scale of the mean monthly temperature at 850 hPa is statistically assessed against gridded GFS analyses. The simulations are based on the global version of the Weather Research and Forecasting model (GWRF) modified appropriately in order to simulate long-term atmospheric circulation. Model initializations are based on a customized version of the Lagged Average Forecast (LAF) formulation. GWRF seasonal scale simulations are initialized from the daily global analyses, assuming each analysis as a perturbation of the previous one due to the long forecast window of 12 months ahead. Evaluation results indicate that the forecast skill is independent of the forecast horizon and reveal a key role of the model initialization on the seasonal predictability.
Reference:
Temperature Seasonal Predictability of the WRF Model (Varlas, G. and Katsafados, P. and Papadopoulos, A.), Chapter in (Karacostas, Theodore, Bais, Alkiviadis, Nastos, Panagiotis T., eds.), Springer International Publishing, 2017.
Bibtex Entry:
@inbook{Varlas2017, author = {Varlas, G. and Katsafados, P. and Papadopoulos, A.}, editor = {Karacostas, Theodore and Bais, Alkiviadis and Nastos, Panagiotis T.}, title = {Temperature Seasonal Predictability of the WRF Model}, booktitle = {Perspectives on Atmospheric Sciences}, year = {2017}, bibyear = {2017}, publisher = {Springer International Publishing}, address = {Cham}, pages = {75--80}, abstract = {It is a common sense that there is no usable forecast skill at seasonal lead times due to the rapid drop-off of the predictability after a few days from the initialization of a simulation. However, there is some skill in predicting anomalies in the seasonal average of the weather such as anomalies of the persistent atmospheric patterns or even deviation from the climatology. In this study, the forecast skill on a seasonal scale of the mean monthly temperature at 850 hPa is statistically assessed against gridded GFS analyses. The simulations are based on the global version of the Weather Research and Forecasting model (GWRF) modified appropriately in order to simulate long-term atmospheric circulation. Model initializations are based on a customized version of the Lagged Average Forecast (LAF) formulation. GWRF seasonal scale simulations are initialized from the daily global analyses, assuming each analysis as a perturbation of the previous one due to the long forecast window of 12 months ahead. Evaluation results indicate that the forecast skill is independent of the forecast horizon and reveal a key role of the model initialization on the seasonal predictability.}, isbn = {978-3-319-35095-0}, doi = {10.1007/978-3-319-35095-0_11}, url = {https://doi.org/10.1007/978-3-319-35095-0_11}, }