极地研究2018，Vol.30Issue(1)：32-41,10.DOI:10.13679/j.jdyj.20170018
双扩散在南极文森湾海域热盐结构演变中的作用
EFFECT OF DOUBLE DIFFUSIVE CONVECTION DURING THE EVOLUTION OF SEAWATER THERMOHALINE STRUCTURE IN VINCENNES BAY, ANTARCTICA
摘要
Abstract
Based on seal CTD data obtained in mid-western areas of Vincennes Bay during March-April 2012, the effect of double diffusive convection during the evolution of the seawater thermohaline structure during the early freezing period was evaluated. Results showed that the effect of double diffusion convection was sub-stantial. The proportion of "diffusion convection" throughout the entire water column was >50%, and strong"diffusion convection" persisted in the deep water from 500 to 800 dbar. The proportion of "salt finger con-vection" in the water column was ≤10% and it occurred in the mid-layers between 300 and 500 dbar. As the Antarctic winter progresses, brine rejection during sea ice formation makes the water increasingly gravita-tionally unstable. "Diffusion convection" produces upward fluxes of heat and salinity. The heat flux is in the range of 0.02-0.5 W·m-2, and the average salinity flux is about 10-8m·s-1. "Salt finger convection" produces downward fluxes of heat and salinity; the average heat flux is about -0.5 W·m-2and the average salinity flux is about -10-8m·s-1. During the early freezing period, continuous cooling and brine rejection force the pro-duction of dense water with low temperature and high salinity. Double diffusion convection (mainly diffu-sive convection) reforms the water properties, making the entire water column denser. Therefore, the con-tribution of double diffusion convection on the formation of dense shelf water in Vincennes Bay is crucial.关键词
陆架水/水体结构演变/双扩散/扩散对流/文森湾/南极Key words
shelf water/evolution of seawater/double diffusion convection/diffusive convection/Vin-cennes Bay/Antarctica引用本文复制引用
张贤良,程灵巧,高郭平..双扩散在南极文森湾海域热盐结构演变中的作用[J].极地研究,2018,30(1):32-41,10.基金项目
国家自然科学基金(41506219)和上海市浦江人才计划(15PJ403000)资助 （41506219）
