Oregon Shelf: Transition to Upwelling

At the beginning of April, we had some extended 20 kt bursts of northerly winds off the Oregon shelf,

(image from www.orcoos.org)
and the glider observations show the upwelling response in the coasatal ocean with deep, cool, salty, low oxygen water moving up onto the shelf.

In addition, to the deep water moving up onto the shelf, the fresh water in the surface layer moves off the shelf, and phytoplankton blooms can be seen in the near surface chlorophyll fluorescence measurements. Compare these sections with the clasic winter conditions below.