Western boundary currents regulated by interaction between ocean eddies and the atmosphere.

Current climate models systematically underestimate the strength of oceanic fronts associated with strong western boundary currents, such as the Kuroshio and Gulf Stream Extensions, and have difficulty simulating their positions at the mid-latitude ocean's western boundaries. Even with an enhanced grid resolution to resolve ocean mesoscale eddies-energetic circulations with horizontal scales of about a hundred kilometres that strongly interact with the fronts and currents-the bias problem can still persist; to improve climate models we need a better understanding of the dynamics governing these oceanic frontal regimes. Yet prevailing theories about the western boundary fronts are based on ocean internal dynamics without taking into consideration the intense air-sea feedbacks in these oceanic frontal regions.

Interannual atmospheric variability forced by the deep equatorial Atlantic Ocean.

Climate variability in the tropical Atlantic Ocean is determined by large-scale ocean-atmosphere interactions, which particularly affect deep atmospheric convection over the ocean and surrounding continents. Apart from influences from the Pacific El Niño/Southern Oscillation and the North Atlantic Oscillation, the tropical Atlantic variability is thought to be dominated by two distinct ocean-atmosphere coupled modes of variability that are characterized by meridional and zonal sea-surface-temperature gradients and are mainly active on decadal and interannual timescales, respectively. Here we report evidence that the intrinsic ocean dynamics of the deep equatorial Atlantic can also affect sea surface temperature, wind and rainfall in the tropical Atlantic region and constitutes a 4.