Zonal overturning circulation and heat flux induced by heaving modes in the world oceans
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摘要: 纬向翻转和纬向热输送是大洋环流和气候系统的重要环节,但是这两个概念目前尚未广泛应用.年际和年代际风应力的变化所导致的heaving(绝热运动)可以形成异常的纬向翻转和纬向热输送.本文采用一个简单的约化重力模式研究世界大洋中heaving所形成的异常纬向翻转和纬向热输送.例如,年代际赤道东风应力的加强可以产生负的纬向翻转(-0.3×106 m3/s)和相应西向的纬向热输送(-11.2 TW).可见,heaving形成的纬向翻转和纬向热输送异常在大洋环流和气候变化中能够起重要的作用.Abstract: Zonal overturning circulation (ZOC) and its associated zonal heat flux (ZHF) are important components of the oceanic circulation and climate system, although these conceptions have not received adequate attentions. Heaving induced by inter-annual and decadal wind stress perturbations can give rise to anomalous ZOC and ZHF. Based on a simple reduced gravity model, the anomalous ZOC and ZHF induced by idealized heaving modes in the world oceans are studied. For example, in a Pacific-like model basin intensified equatorial easterly on decadal time scales can lead to a negative ZOC with a non-negligible magnitude (-0.3×106 m3/s) and a considerable westward ZHF with an amplitude of -11.2 TW. Thus, anomalous ZOC and ZHF may consist of a major part of climate signals on decadal time scales and thus play an important role in the oceanic circulation and climate change.
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Key words:
- adiabatic motions /
- heaving /
- wind-driven circulation /
- zonal overturning circulation
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