Simulation of the deep and intermediate Pacific meridional overturning circulation
The strength of deep PMOC is significantly increased by using the stratification-dependent remote mixing and geothermal heating. The northward volume transport of deep water originated from the Southern Ocean is slightly smaller than an observational estimate by mooring observation, whereas the isotope ratio of radiocarbon shows the consistency with observation in the deep Pacific Ocean. This discrepancy implies the interannual or decadal variability of northward volume transport in the lower deep Pacific Ocean.
We will obtain (1) the fractions of the deep water returning to the Southern Ocean and inflowing the Indian Oceans and (2) the connection of circulations between the intermediate and deep layers in the North Pacific Ocean by using virtual Eulerian and Lagrangian tracers. Since the intermediate PMOC is influenced by the eddy activity, 1/6 degree OGCM experiment is additionally conducted. We will show these results in our presentation.