2.1.1 Western boundary currents:
The Gulf Stream and its seasonal variations
Satellite altimetry's contribution to ocean circulation studies.
Does the Gulf Stream vary with the seasons? Or with the years? A few diagrams illustrate a first approach.
The Gulf Stream, season by season
Here we are considering two seasons: autumn (October-November) and Spring (April-May). For each one we:
- compute the temporal average of the absolute dynamic topography all along a cross-section in longitude (70°W),
- plot diagrams showing how these averaged dynamic heights vary with latitude.
Seen in this way, the Gulf Stream appears at approximately 37°N, and seems further north in October (black curves) than in April (red curves), as well as appearing more intense. These differences could mirror a seasonal or inter-annual signal.
|fig 1: 2001-2002||fig 2: 2002-2003|
|fig 3: 2003-2004||fig 4: 2004-2005
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