Predicting tropical cyclone(TC)genesis is of great societal importance but scientifically challenging.It requires fineresolution coupled models that properly represent air−sea interactions in the atmospheric responses...Predicting tropical cyclone(TC)genesis is of great societal importance but scientifically challenging.It requires fineresolution coupled models that properly represent air−sea interactions in the atmospheric responses to local warm sea surface temperatures and feedbacks,with aid from coherent coupled initialization.This study uses three sets of highresolution regional coupled models(RCMs)covering the Asia−Pacific(AP)region initialized with local observations and dynamically downscaled coupled data assimilation to evaluate the predictability of TC genesis in the West Pacific.The APRCMs consist of three sets of high-resolution configurations of the Weather Research and Forecasting−Regional Ocean Model System(WRF-ROMS):27-km WRF with 9-km ROMS,and 9-km WRF with 3-km ROMS.In this study,a 9-km WRF with 9-km ROMS coupled model system is also used in a case test for the predictability of TC genesis.Since the local sea surface temperatures and wind shear conditions that favor TC formation are better resolved,the enhanced-resolution coupled model tends to improve the predictability of TC genesis,which could be further improved by improving planetary boundary layer physics,thus resolving better air−sea and air−land interactions.展开更多
Mesoscale air-sea interactions play a critical role in damping eddy activities.However,how mesoscale heat flux influences the distribution of eddy kinetic energy(EKE)in the wavenumber space remains unclear.In this stu...Mesoscale air-sea interactions play a critical role in damping eddy activities.However,how mesoscale heat flux influences the distribution of eddy kinetic energy(EKE)in the wavenumber space remains unclear.In this study,we investigate the EKE and temperature variance(T_(var))budgets in the Kuroshio Extension(KE)region using wavenumber spectral analysis based on 1/10°coupled climate simulations.These simulations include a standard high-resolution simulation and a smoothed simulation that overlooks mesoscale heat flux.By comparing the differences between these models,we confirm that air-sea heat exchange significantly dissipates Tvar.Neglecting mesoscale heat flux results in a 60% underestimation of the Tvar damping rate,which in turn increases energy transfer to EKE through the vertical buoyancy flux by 22%.This enhanced vertical buoyancy flux leads to a 20% higher EKE level and larger energy budget terms,particularly in the diffusion term,which is closely related to wind power.Furthermore,underestimating air-sea heat exchange could lead to an overestimation of the inverse kinetic energy cascade,thereby distorting the overall energy budget in the KE region.展开更多
A regional coupled prediction system for the Asia-Pacific(AP-RCP)(38°E-180°,20°S-60°N) area has been established.The AP-RCP system consists of WRF-ROMS(Weather Research and Forecast,and Regional Oc...A regional coupled prediction system for the Asia-Pacific(AP-RCP)(38°E-180°,20°S-60°N) area has been established.The AP-RCP system consists of WRF-ROMS(Weather Research and Forecast,and Regional Ocean Model System) coupled models combined with local observational information through dynamically downscaling coupled data assimilation(CDA).The system generates 18-day forecasts for the atmosphere and ocean environment on a daily quasi-operational schedule at Pilot National Laboratory for Marine Science and Technology(Qingdao)(QNLM),consisting of 2 different-resolution coupled models:27 km WRF coupled with 9 km ROMS,9 km WRF coupled with 3 km ROMS,while a version of 3 km WRF coupled with 3 km ROMS is in a test mode.This study is a first step to evaluate the impact of high-resolution coupled model with dynamically downscaling CDA on the extended-range predictions,focusing on forecasts of typhoon onset,improved precipitation and typhoon intensity forecasts as well as simulation of the Kuroshio current variability associated with mesoscale oceanic activities.The results show that for realizing the extended-range predictability of atmospheric and oceanic environment characterized by statistics of mesoscale activities,a fine resolution coupled model resolving local mesoscale phenomena with balanced and coherent coupled initialization is a necessary first step.The next challenges include improving the planetary boundary physics and the representation of air-sea and air-land interactions to enable the model to resolve kilometer or sub-kilometer processes.展开更多
A major challenge in analysis of huge amounts of ocean data is the complexity of the data and the inherent complexity of ocean dynamic processes.Interactive visual analysis serves as an efficient complementary approac...A major challenge in analysis of huge amounts of ocean data is the complexity of the data and the inherent complexity of ocean dynamic processes.Interactive visual analysis serves as an efficient complementary approach for the detection of various phenomena or patterns,and correlation exploring or comparing multiple variables in researchers daily work.Firstly,this paper presents a basic concept of the ocean data produced from numerous measurement devices or computer simulations.The characteristics of ocean data and the related data processing techniques are also described.Secondly,the main tasks of ocean data analysis are introduced.Based on the main analysis tasks in the field of oceanography,the survey emphasizes related interactive visualization techniques and tools from four aspects:visualization of multiple ocean environmental elements and multivariate analysis,ocean phenomena identification and tracking,patterns or correlation discovery,ensembles and uncertainties exploration.Finally,the opportunities are discussed for future studies.展开更多
基金supported by the National Key Research&Development Program of China(Grant Nos.2017YFC1404100 and 2017YFC1404104)the National Natural Science Foundation of China(Grant Nos.41775100 and 41830964)。
文摘Predicting tropical cyclone(TC)genesis is of great societal importance but scientifically challenging.It requires fineresolution coupled models that properly represent air−sea interactions in the atmospheric responses to local warm sea surface temperatures and feedbacks,with aid from coherent coupled initialization.This study uses three sets of highresolution regional coupled models(RCMs)covering the Asia−Pacific(AP)region initialized with local observations and dynamically downscaled coupled data assimilation to evaluate the predictability of TC genesis in the West Pacific.The APRCMs consist of three sets of high-resolution configurations of the Weather Research and Forecasting−Regional Ocean Model System(WRF-ROMS):27-km WRF with 9-km ROMS,and 9-km WRF with 3-km ROMS.In this study,a 9-km WRF with 9-km ROMS coupled model system is also used in a case test for the predictability of TC genesis.Since the local sea surface temperatures and wind shear conditions that favor TC formation are better resolved,the enhanced-resolution coupled model tends to improve the predictability of TC genesis,which could be further improved by improving planetary boundary layer physics,thus resolving better air−sea and air−land interactions.
基金supported by the Natu-ral Science Foundation of China and Fundamental Research Funds for the Central Universities(Grant Nos.42176006,42422601,202241006 to H.Y.)the Natural Science Foundation of China(Grant No.42225601 to Z.C.).
文摘Mesoscale air-sea interactions play a critical role in damping eddy activities.However,how mesoscale heat flux influences the distribution of eddy kinetic energy(EKE)in the wavenumber space remains unclear.In this study,we investigate the EKE and temperature variance(T_(var))budgets in the Kuroshio Extension(KE)region using wavenumber spectral analysis based on 1/10°coupled climate simulations.These simulations include a standard high-resolution simulation and a smoothed simulation that overlooks mesoscale heat flux.By comparing the differences between these models,we confirm that air-sea heat exchange significantly dissipates Tvar.Neglecting mesoscale heat flux results in a 60% underestimation of the Tvar damping rate,which in turn increases energy transfer to EKE through the vertical buoyancy flux by 22%.This enhanced vertical buoyancy flux leads to a 20% higher EKE level and larger energy budget terms,particularly in the diffusion term,which is closely related to wind power.Furthermore,underestimating air-sea heat exchange could lead to an overestimation of the inverse kinetic energy cascade,thereby distorting the overall energy budget in the KE region.
基金supported by the National Key Research and Development Program of China(2017YFC1404100,2017YFC1404104)the National Natural Science Foundation of China(41775100,41830964)+1 种基金the Shandong Province’s"Taishan"Scientist Project(2018012919)the collaborative project between the Ocean University of China(OUC),Texas A&M University(TAMU)and the National Center for Atmospheric Research(NCAR)and completed through the International Laboratory for High Resolution Earth System Prediction(iHESP)-a collaboration among QNLM,TAMU and NCAR。
文摘A regional coupled prediction system for the Asia-Pacific(AP-RCP)(38°E-180°,20°S-60°N) area has been established.The AP-RCP system consists of WRF-ROMS(Weather Research and Forecast,and Regional Ocean Model System) coupled models combined with local observational information through dynamically downscaling coupled data assimilation(CDA).The system generates 18-day forecasts for the atmosphere and ocean environment on a daily quasi-operational schedule at Pilot National Laboratory for Marine Science and Technology(Qingdao)(QNLM),consisting of 2 different-resolution coupled models:27 km WRF coupled with 9 km ROMS,9 km WRF coupled with 3 km ROMS,while a version of 3 km WRF coupled with 3 km ROMS is in a test mode.This study is a first step to evaluate the impact of high-resolution coupled model with dynamically downscaling CDA on the extended-range predictions,focusing on forecasts of typhoon onset,improved precipitation and typhoon intensity forecasts as well as simulation of the Kuroshio current variability associated with mesoscale oceanic activities.The results show that for realizing the extended-range predictability of atmospheric and oceanic environment characterized by statistics of mesoscale activities,a fine resolution coupled model resolving local mesoscale phenomena with balanced and coherent coupled initialization is a necessary first step.The next challenges include improving the planetary boundary physics and the representation of air-sea and air-land interactions to enable the model to resolve kilometer or sub-kilometer processes.
基金wish to acknowledge the financial support from the National Natural Science Foundation of China(No.41706010,U1706218,41576011)the Major Research plan of the National Natural Science Foundation of Shandong Province(No.ZR2018ZB0852).
文摘A major challenge in analysis of huge amounts of ocean data is the complexity of the data and the inherent complexity of ocean dynamic processes.Interactive visual analysis serves as an efficient complementary approach for the detection of various phenomena or patterns,and correlation exploring or comparing multiple variables in researchers daily work.Firstly,this paper presents a basic concept of the ocean data produced from numerous measurement devices or computer simulations.The characteristics of ocean data and the related data processing techniques are also described.Secondly,the main tasks of ocean data analysis are introduced.Based on the main analysis tasks in the field of oceanography,the survey emphasizes related interactive visualization techniques and tools from four aspects:visualization of multiple ocean environmental elements and multivariate analysis,ocean phenomena identification and tracking,patterns or correlation discovery,ensembles and uncertainties exploration.Finally,the opportunities are discussed for future studies.
