Sea Surface Temperature Gradients

The existence of ocean fronts influences many aspects of the climate system, including ocean mixing, air-sea coupling, cloud and wind patterns, and marine productivity and biomass. A significant tool in evaluating and understanding the role of ocean fronts is satellite-derived sea surface temperature fields. This work addresses several questions regarding the coupled atmosphere/ocean system in the vicinity of sea surface temperature gradients.

  • What is the spatial and temporal variability of SST gradients (as a function of gradient magnitude) as seen in satellite-derived SST fields?
  • How does this variability relate to the upper ocean temperature structure?
  • What role do surface fluxes play in this variability, and how are they in turn influenced by it?
  • What role does diurnal warming of the sea surface temperature play in both SST frontal evolution and in the atmospheric response? These questions are addressed primarily through satellite data analysis of surface and atmospheric properties, and secondarily through an upper-ocean model.


The usefulness of these data is however dependent on how well they represent the gradients occurring over the depth of the ocean mixed layer. Previous work has demonstrated that there is a coupling between the ocean and atmosphere in these regions that plays some role in atmospheric dynamics, which is not yet well understood. It is also clear that surface fluxes can play a role in altering the surface expression of these fronts, although the extent to which this occurs and whether this is simply a masking of the frontal structure below the very uppermost portion of the ocean, is not as well understood.