Appreciate your interest binntho, as b_lumenkraft mentioned there are likely several/many factors at play. I'm certainly no expert, but the the counter clockwise motion to me suggests there is some upwelling. I'm basing this on how the atmosphere works, low pressure is associated with rising air.
With so little open water, wind stresses seem to be minimal, but perhaps a southerly flow over the land masses of the CAA *could* result in modest coastal upwelling.
The most mysterious question to me, is whether these exist under the ice, or do they form only due to the opening. I haven't a clue. It'll be interesting to see how they behave going forward.
I think features like this emphasize the value of these sub daily images available from RAMMB, and am grateful that others, especially b_lumenkraft, have also taken an interest.