Isopycnal Mixing Controls Deep Ocean Ventilation Academic Article uri icon

abstract

  • AbstractClimate models often parameterize isopycnal mixing by mesoscale eddies using a diffusion operator that acts in the isopycnal direction, multiplied by an isopycnalmixing coefficient. The magnitude of this coefficient is uncertain, with observational estimates ranging from 10 to 10,000m2/s. In an idealizedgeometry ocean model, the isopycnalmixing coefficient is varied across a similar range without allowing the circulation to change: This leads to large changes in the ventilation of the deep ocean. Passive tracers are used to assess the impact of varying the isopycnalmixing coefficient on water mass distributions. Increasing the isopycnalmixing coefficient from 50 to 5,000m2/s leads to a 63% reduction in the amount of North Atlantic Deep Water and a doubling in the amount of Antarctic Bottom Water in the deep Pacific ocean. This change is associated with a 700yr reduction in the ideal age of water in the deep Pacific ocean.

published proceedings

  • GEOPHYSICAL RESEARCH LETTERS

altmetric score

  • 4.1

author list (cited authors)

  • Jones, C. S., & Abernathey, R. P.

citation count

  • 21

complete list of authors

  • Jones, CS||Abernathey, Ryan P

publication date

  • November 2019