Thermal Feedback on Wind Stress as a Contributing Cause of Climate Variability

Abstract

A model that isolates the interaction between midlatitude ocean gyres and the wind stress due to atmospheric baroclinic eddies is formulated. The ocean and atmosphere are coupled through their respective heat balances and global heat and momentum conservations are enforced. The ocean flow creates a steep oceanic thermal front at the midlatitude intergyre boundary. This frontogenesis sharpens the atmospheric temperature gradients and locally increases the atmospheric eddy heat transport. The result is a well-defined storm track that, because of the delayed adjustment of the gyres to the wind stress, oscillates in time with a period of about 18 yr.