Estimation of eddy heat transport in the global ocean from Argo data
-
摘要: The Argo data are used to calculate eddy (turbulence) heat transport (EHT) in the global ocean and analyze its horizontal distribution and vertical structure. We calculate the EHT by averaging all the v',T' profiles within each 2°× 2° bin. The velocity and temperature anomalies are obtained by removing their climatological values from the Argo "instantaneous" values respectively. Through the Student's t-test and an error evaluation, we obtained a total of 87% Argo bins with significant depth-integrated EHTs (D-EHTs). The results reveal a positive-and-negative alternating D-EHT pattern along the western boundary currents (WBC) and Antarctic Circumpolar Current (ACC). The zonally-integrated D-EHT (ZI-EHT) of the global ocean reaches 0.12 PW in the northern WBC band and -0.38 PW in the ACC band respectively. The strong ZI-EHT across the ACC in the global ocean is mainly caused by the southern Indian Ocean. The ZI-EHT in the above two bands accounts for a large portion of the total oceanic heat transport, which may play an important role in regulating the climate. The analysis of vertical structures of the EHT along the 35°N and 45°S section reveals that the oscillating EHT pattern can reach deep in the northern WBC regions and the Agulhas Return Current (ARC) region. It also shows that the strong EHT could reach 600 m in the WBC regions and 1 000min the ARC region, with themaximum mainly located between 100 and 400 mdepth. The results would provide useful information for improving the parameterization scheme inmodels.
-
关键词:
- eddyheattransport /
- Argo /
- mesoscaleeddy /
- globalocean
Abstract: The Argo data are used to calculate eddy (turbulence) heat transport (EHT) in the global ocean and analyze its horizontal distribution and vertical structure. We calculate the EHT by averaging all the v',T' profiles within each 2°× 2° bin. The velocity and temperature anomalies are obtained by removing their climatological values from the Argo "instantaneous" values respectively. Through the Student's t-test and an error evaluation, we obtained a total of 87% Argo bins with significant depth-integrated EHTs (D-EHTs). The results reveal a positive-and-negative alternating D-EHT pattern along the western boundary currents (WBC) and Antarctic Circumpolar Current (ACC). The zonally-integrated D-EHT (ZI-EHT) of the global ocean reaches 0.12 PW in the northern WBC band and -0.38 PW in the ACC band respectively. The strong ZI-EHT across the ACC in the global ocean is mainly caused by the southern Indian Ocean. The ZI-EHT in the above two bands accounts for a large portion of the total oceanic heat transport, which may play an important role in regulating the climate. The analysis of vertical structures of the EHT along the 35°N and 45°S section reveals that the oscillating EHT pattern can reach deep in the northern WBC regions and the Agulhas Return Current (ARC) region. It also shows that the strong EHT could reach 600 m in the WBC regions and 1 000min the ARC region, with themaximum mainly located between 100 and 400 mdepth. The results would provide useful information for improving the parameterization scheme inmodels.-
Key words:
- eddy heat transport /
- Argo /
- mesoscale eddy /
- global ocean
-
Chen Gengxin, Gan Jianping, Xie Qiang, et al. 2012. Eddy heat and salttransports in the South China Sea and their seasonal modulations.J Geophys Res, 117: C05021, doi: 10.1029/2011JC007724 Chinn B S, Gille S T. 2007. Estimating eddy heat flux fromfloat data inthe North Atlantic: The impact of temporal sampling interval.J Atmos Ocean Tech, 24: 923-934 Cressman G P. 1959. An operational objective analysis system. Mon Weather Rev, 87: 367-374 Gille S T. 2003. Float observations of the Southern Ocean. Part Ⅱ: Eddyfluxes. J Phys Oceanogr, 33: 1182-1196 Hausmann U, Czaja A. 2012. The observed signature of mesoscaleeddies in sea surface temperature and the associated heat transport.Deep-Sea Research: Part Ⅰ, 70: 60-72 Jayne S R, Marotzke J. 2002. The oceanic eddy heat transport. J PhysOceanogr, 32: 3328-3345 Killworth P. 1998. Eddy parameterization in large scale flow. In: ChassignetEP, Verron J, eds. Ocean Modeling and Parameterization.Dordrecht: Kluwer Acad. Press, 253-268 Lee T, Fukumori I, Tang B. 2004. Temperature advection: internal versusexternal processes. J Phys Oceanogr, 34: 1936-1944 Marshall J, Shutts G. 1981. A note on rotational and divergent eddyfuxes. J Phys Oceanogr, 11: 1677-1680 Meijers A J, Bindoff N L, Roberts J L. 2007. On the total,mean, and eddyheat and freshwater transports in the Southern Hemisphereof a global ocean model. J Phys Oceanogr, 37: 277-295 Montgomery R B. 1974. Comment on‘seasonal variability of the FloridaCurrent’by Niiler and Richardson. JMar Res, 32: 533-535 Phillips H E, Rintoul S R. 2000. Eddy variability and energetic fromdirect current measurements in the Antarctic Circumpolar Currentsouth of Australia. J Phys Oceanogr, 30: 3050-3076 Qiu B, Chen S. 2005. Eddy-induced heat transport in the subtropicalNorth Pacific from Argo, TMI, and altimetry measurements.J Phys Oceanogr, 35: 458-473 Roemmich D, Gilson J, Cornuelle B, et al. 2001. Mean and timevaryingmeridional transport of heat at tropical/subtropicalboundary of the North Pacific Ocean. J Geophys Res, 106: 8957-8970 Souza J M A C, de Boyer Montégut C, Cabanes C, et al. 2011. Estimationof the Agulhas ring impacts on meridional heat fluxesand transport using ARGOfloats and satellite data. Geophys ResLett, 38: L21602, doi: 10.1029/2011GL049359 Stammer D. 1998. On eddy characteristics, eddy transports, andmeanflow properties. J Phys Oceanogr, 28: 727-739 Trenberth K E, Carron J M. 2001. Estimates of atmosphere and oceanmeridional heat transports. J Climate, 14: 3433-3442 Volkov D L, Lee T, Fu L L. 2008. Eddy-induced meridional heattransport in the ocean. Geophys Res Lett, 35: L20601, doi: 10.1029/2008GL035490 Walkden G J, Heywood K J, Stevens D P. 2008. Eddy heat fluxesfrom direct current measurements of the Antarctic PolarFront in Shag Rocks Passage. Geophys Res Lett, 35: L06602, doi: 10.1029/2007GL032767 Wang Xidong, Li Wei, Qi Yiquan, et al. 2012. Heat, salt and volumetransports by eddies in the vicinity of the Luzon Strait. Deep SeaRes Part Ⅰ, 61: 21-33 Wunsch C. 1999. Where do ocean eddy heat fluxes matter? J GeophysRes 104: 13235-13249 Yim B Y, Noh Y, You S H, et al. 2010. The vertical structure of eddyheat transport simulated by an eddy-resolving OGCM. J PhysOceanogr, 40: 340-353
点击查看大图
计量
- 文章访问数: 1159
- HTML全文浏览量: 23
- PDF下载量: 2145
- 被引次数: 0