Atmospheric responses and feedback to the meridional ocean heat transport in the North Pacific
Atmospheric responses and feedback to the meridional ocean heat transport in the North Pacific
复制标题
北太平洋经向海洋热传输的大气响应和反馈
DOI：
10.1175/jcli-d-16-0055.1
复制
发表时间：
2017
影响因子：
4.9
通讯作者：
and Hasumi Hiroyasu
中科院分区：
文献类型：
--
作者：
Tatebe Hiroaki;Kurogi Masao;and Hasumi Hiroyasu
利用与嵌入西北太平洋的高分辨率区域海洋模式相互关联的全球气候模式，研究了大气对经向海洋热输送(OHT)的响应和反馈。与没有区域模式的全球气候模式相比，由于西部边界流和中尺度涡旋增加了平均北上海洋热输送(OHT)，黑潮-Oyashio延伸区(KOE)的净热量供应增加。由此产生的海面温度升高加剧了经向海温梯度，增强了地面热通量的跨锋面差异，从而增强了对流层低层斜压性。这些变化导致北太平洋冬季风暴路径向北偏转和加强，从而导致平均西风急流的太平洋-北美(PNA)型反气旋响应。与风暴路径活动增强相关的涡旋北上大气热通量(AHF)的增加被平均北上大气热通量的减少所补偿。大气环流的变化使东北太平洋东部向北的平均OHT值减小，补偿了KOE区向北的平均OHT值的增加。曾经被KOE海温锋面激发的大气响应，稳定了横贯北太平洋的OHT。本文的模拟结果表明，在北太平洋气候平均态的形成过程中，海气耦合过程中存在着盆地范围内的类BJernes补偿作用。
Atmospheric responses and feedback to meridional ocean heat transport (OHT) have been investigated using a global climate model that is interactively connected with a high-resolution regional ocean model embedded in the western North Pacific. Compared with a global climate model without the regional model, the net heat supply into the Kuroshio–Oyashio Extension (KOE) region is increased as a result of the increase of the mean northward ocean heat transport (OHT) by the western boundary currents and mesoscale eddies. Resultant sea surface temperature (SST) rise sharpens the meridional SST gradient and reinforces the cross-frontal difference of the surface heat flux and thereby enhances lower-tropospheric baroclinicity. These changes cause northward deflection and strengthening of the wintertime storm track over the North Pacific, which leads to the Pacific–North American (PNA)-like pattern anticyclonic response of the mean westerly jet. The increase of the eddy northward atmospheric heat flux (AHF) associated with the enhanced storm-track activity is compensated by the decrease of the mean northward AHF. The changes of the atmospheric circulations reduce the mean northward OHT in the eastern North Pacific that compensates the increase of the mean northward OHT in the KOE region. The atmospheric responses, which have once been excited by the SST fronts in the KOE region, stabilize the trans–North Pacific OHT. The modeling results herein suggest that basinwide Bjerknes-like compensation works in air–sea coupled processes for the formation of the climatic mean state in the North Pacific.