Internal lee waves play an important role in transferring energy from eddies to small scale mixing.However,the energy conversion from eddies into lee waves in the global ocean remains poorly understood.Conversion rate...Internal lee waves play an important role in transferring energy from eddies to small scale mixing.However,the energy conversion from eddies into lee waves in the global ocean remains poorly understood.Conversion rates from eddies and from mean fl ow in the global ocean were diff erentiated using single beam sounding data,stratifi cation from climatology,eddy velocity,and mean fl ow from a global ocean model.The global integral energy conversion from eddies is estimated to be 0.083 TW and is almost twice as that from the mean fl ow.A new method was developed to study the uncertainties of energy conversion caused by dealing with the topographic data.Results show that diff erent data processing procedures,and the resolution and accuracy of topographic data have a signifi cant impact on the estimated global energy conversion.展开更多
An eddy-resolving four-dimensional variational(adjoint)data assimilation and state estimate was constructed for the low-to mid-latitude Pacifi c,Indian Oceans,and South China Sea based on the framework of“Estimating ...An eddy-resolving four-dimensional variational(adjoint)data assimilation and state estimate was constructed for the low-to mid-latitude Pacifi c,Indian Oceans,and South China Sea based on the framework of“Estimating the Circulation and Climate of the Oceans(ECCO)”.It is named as the Two Oceans One Sea State Estimate(TOOSSE).It fi ts a model to a number of modern observations of 2015-2016,including the Argo fl oat temperature and salinity,satellite altimetric sea surface anomalies,by adjusting initial temperature and salinity,sea surface boundary conditions,and background diapycnal diff usivities.In total,~50%of the original model-data misfi ts have been eliminated,and the estimated state agreed well with a variety of independent observations at meso-to large scales,and on the intra-seasonal to interannual timescales.Mesoscale variability is systematically strengthened in TOOSSE and closer to observations than that without data assimilation,which is especially evidenced by the improved simulation of the mesoscale tropical instability waves(TIWs).Adjustments to ocean surface forcing parameters exhibit both large and frontal/mesoscale structures,and the magnitude reach 20%-100%of the fi rst guesses;the adjustments to diapycnal diff usivity exhibit an obvious elevation(decrement)in(below)the thermocline in the equatorial band.The results indicate that TOOSSE represents a dynamically and thermodynamically consistent ocean state estimate of the 2015-2016 Indo-Pacifi c Ocean,and can be widely utilized for regional process studies.展开更多
基金Supported by the Guangdong Basic and Applied Basic Research Fund(No.2020A1515010498)the National Natural Science Foundation of China(Nos.41776034,41706025)。
文摘Internal lee waves play an important role in transferring energy from eddies to small scale mixing.However,the energy conversion from eddies into lee waves in the global ocean remains poorly understood.Conversion rates from eddies and from mean fl ow in the global ocean were diff erentiated using single beam sounding data,stratifi cation from climatology,eddy velocity,and mean fl ow from a global ocean model.The global integral energy conversion from eddies is estimated to be 0.083 TW and is almost twice as that from the mean fl ow.A new method was developed to study the uncertainties of energy conversion caused by dealing with the topographic data.Results show that diff erent data processing procedures,and the resolution and accuracy of topographic data have a signifi cant impact on the estimated global energy conversion.
基金Supported by the National Key R&D Program of China(No.2016YFC1401703)the Strategic Priority Research Program of CAS(No.XDB42000000)+2 种基金the Key Research Program of Frontier Sciences of CAS(No.QYZDB-SSW-DQC030)the National Natural Science Foundation of China(Nos.41976012,41730534,41806015,Y72143101B)the Aoshan Talents Program by the QNML(No.2017ASTCPES03)。
文摘An eddy-resolving four-dimensional variational(adjoint)data assimilation and state estimate was constructed for the low-to mid-latitude Pacifi c,Indian Oceans,and South China Sea based on the framework of“Estimating the Circulation and Climate of the Oceans(ECCO)”.It is named as the Two Oceans One Sea State Estimate(TOOSSE).It fi ts a model to a number of modern observations of 2015-2016,including the Argo fl oat temperature and salinity,satellite altimetric sea surface anomalies,by adjusting initial temperature and salinity,sea surface boundary conditions,and background diapycnal diff usivities.In total,~50%of the original model-data misfi ts have been eliminated,and the estimated state agreed well with a variety of independent observations at meso-to large scales,and on the intra-seasonal to interannual timescales.Mesoscale variability is systematically strengthened in TOOSSE and closer to observations than that without data assimilation,which is especially evidenced by the improved simulation of the mesoscale tropical instability waves(TIWs).Adjustments to ocean surface forcing parameters exhibit both large and frontal/mesoscale structures,and the magnitude reach 20%-100%of the fi rst guesses;the adjustments to diapycnal diff usivity exhibit an obvious elevation(decrement)in(below)the thermocline in the equatorial band.The results indicate that TOOSSE represents a dynamically and thermodynamically consistent ocean state estimate of the 2015-2016 Indo-Pacifi c Ocean,and can be widely utilized for regional process studies.
