We received data from PCCS for four additional cruises. According to Stormy, Pseudocalanus is still running the show in the Bay. Here's the model's take on Pseudocalanus abundance on 2/25, the day of the last survey:
The images are no assimilation (left), assimilating just the January cruises (middle), and assimilating all of the cruises (right). Our model dynamics have Pseudocalanus declining during this time of year, which explains the decrease from left to right in the images. Basically, since Pseudocalanus is higher than normal this year, when we assimilate a cruise, we bump up the abundance. The model dynamics then operate, and the population goes down. So, when we run the model through today, the abundances decrease further:
Interestingly, the image on the right has lower abundance than the one in the middle--something we'll have to look into.
One more comment on the forecasts. We're still waiting on the 2009 circulation fields. So, each ensemble member in the assimilation chooses a flow field from a previous year. This effectively accounts for our uncertainty in the circulation field, assuming that this year is not too far from normal. For the forward run (images above), I ran the model with each of the prior year fields and averaged the results.
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