Double diffusive finger convection at the top of the core

我们预计在地核的顶部会有一层，其中化学成分的梯度推动对流，而温度梯度则相反。在海洋中经常会遇到类似的情况，盐度驱动对流，而对流则受到温度分层的阻碍。在这种情况下，盐指出现了，这是一种细长的结构，尽管密度分层稳定，但流体在其中运动。除了地球自转可能对核心对流有影响，而对海洋中的指状对流几乎没有影响之外，地核肯定也会有类似的流动。该项目利用实验室实验来确定全球自转对指状对流的影响及其对地核可能产生的后果。

We expect a layer at the top of the Earth's core in which gradients in chemical composition drive convection while the temperature gradient opposes it. A similar situation is frequently met in the oceans, in which salinity drives convection which is impeded by the temperature layering. Salt fingers appear in this case, which are slender structures in which fluid moves despite a stable density stratification. A similar flow must be expected in the Earth's core, except that the rotation of the Earth presumably matters for core convection whereas it is mostly irrelevant for finger convection in the oceans. This project uses laboratory experiments to determine the effect of global rotation on finger convection and its possible consequences for the Earth's core.