This study provides a preliminary evaluation of the ensemble forecasting capabilities of the Model for Prediction Across Scales-Atmosphere(MPAS-A)for tropical cyclones(TCs)affecting Zhejiang Province and adjacent offs...This study provides a preliminary evaluation of the ensemble forecasting capabilities of the Model for Prediction Across Scales-Atmosphere(MPAS-A)for tropical cyclones(TCs)affecting Zhejiang Province and adjacent offshore waters in the East China Sea.Five recent high-impact TCs were retrospectively simulated using a global 60-3 km variable-resolution mesh and an eight-member ensemble that samples key physics parameterizations,including cumulus,microphysics,boundary layer,and surface layer schemes.Ensemble-mean and spread characteristics of track and intensity forecasts were assessed against best-track data from the China Meteorological Administration(CMA),while near-surface wind predictions were evaluated using tower-based observations during Typhoon Muifa(2022).Track forecasts exhibited promising skill,with median errors under 50 km at 24 h and 100 km at 48 h,while the ensemble mean was typically more accurate than the median and comparable to operational forecasts.Intensity forecasts showed larger spread and systematic biases,particularly in maximum wind speed,highlighting the influence of boundary-layer physics on ensemble variance.Case studies illustrate how differing physics choices drive divergence in storm translation,steering flow,and inner-core structure.Comparison with tower observations confirmed that the ensemble has the potential to bracket uncertainty in near-surface wind forecasts,although storm position errors remain a key limiting factor.Despite high computational cost,MPAS-A ensembles demonstrate strong potential for probabilistic TC forecasting and offshore wind risk management in this region.展开更多
利用MPAS-A(The Model for Prediction Across Scales-Atmosphere)模式设计了中东太平洋热带辐合带CEP-ITCZ(Intertropical Convergence Zone over Central and Eastern Pacific)对两类厄尔尼诺SST(Sea Surface Temperature)异常的敏感...利用MPAS-A(The Model for Prediction Across Scales-Atmosphere)模式设计了中东太平洋热带辐合带CEP-ITCZ(Intertropical Convergence Zone over Central and Eastern Pacific)对两类厄尔尼诺SST(Sea Surface Temperature)异常的敏感性试验,通过试验结果与两类厄尔尼诺年实际大气异常的对比,初步解释了CEP-ITCZ在两类厄尔尼诺年产生不同异常的可能原因。通过CP-EL试验发现,热带太平洋SST异常的第一模态会使中东太平洋低层风场辐合增强,但对辐合带的位置影响不大,与中部型厄尔尼诺对CEP-ITCZ的影响基本一致。通过EP-EL试验发现,热带太平洋SST异常的第二模态会使中东太平洋低层风场产生较大异常,辐合带中心向南移动,辐合带明显减弱增宽,与东部型厄尔尼诺对CEP-ITCZ的影响基本一致。展开更多
基金supported by Zhejiang Provincial Natural Science Foundation of China under Grant No.LQ24D050001.
文摘This study provides a preliminary evaluation of the ensemble forecasting capabilities of the Model for Prediction Across Scales-Atmosphere(MPAS-A)for tropical cyclones(TCs)affecting Zhejiang Province and adjacent offshore waters in the East China Sea.Five recent high-impact TCs were retrospectively simulated using a global 60-3 km variable-resolution mesh and an eight-member ensemble that samples key physics parameterizations,including cumulus,microphysics,boundary layer,and surface layer schemes.Ensemble-mean and spread characteristics of track and intensity forecasts were assessed against best-track data from the China Meteorological Administration(CMA),while near-surface wind predictions were evaluated using tower-based observations during Typhoon Muifa(2022).Track forecasts exhibited promising skill,with median errors under 50 km at 24 h and 100 km at 48 h,while the ensemble mean was typically more accurate than the median and comparable to operational forecasts.Intensity forecasts showed larger spread and systematic biases,particularly in maximum wind speed,highlighting the influence of boundary-layer physics on ensemble variance.Case studies illustrate how differing physics choices drive divergence in storm translation,steering flow,and inner-core structure.Comparison with tower observations confirmed that the ensemble has the potential to bracket uncertainty in near-surface wind forecasts,although storm position errors remain a key limiting factor.Despite high computational cost,MPAS-A ensembles demonstrate strong potential for probabilistic TC forecasting and offshore wind risk management in this region.
文摘利用MPAS-A(The Model for Prediction Across Scales-Atmosphere)模式设计了中东太平洋热带辐合带CEP-ITCZ(Intertropical Convergence Zone over Central and Eastern Pacific)对两类厄尔尼诺SST(Sea Surface Temperature)异常的敏感性试验,通过试验结果与两类厄尔尼诺年实际大气异常的对比,初步解释了CEP-ITCZ在两类厄尔尼诺年产生不同异常的可能原因。通过CP-EL试验发现,热带太平洋SST异常的第一模态会使中东太平洋低层风场辐合增强,但对辐合带的位置影响不大,与中部型厄尔尼诺对CEP-ITCZ的影响基本一致。通过EP-EL试验发现,热带太平洋SST异常的第二模态会使中东太平洋低层风场产生较大异常,辐合带中心向南移动,辐合带明显减弱增宽,与东部型厄尔尼诺对CEP-ITCZ的影响基本一致。
