Phytoplankton Predictability in NorCPM1

Seminar by Dr. Filippa Fransner from University of Bergen

10 February 2023
KST 10:30 – 11:30

The Seminar is being held in Room 1010 (Jasmin) – Integrated mechanical engineering building. Click here for the campus map.

Phytoplankton dynamics has been shown to be predictable up to three years ahead in tropical and subtropical seas, while several studies indicate less predictability at higher latitudes. Whether this low predictability comes as a result of imperfect models (and/or observations), choice of skill scores, or if phytoplankton dynamics in fact are unpredictable, remains to be investigated.

In this talk, I look deeper into phytoplankton predictability in different regions of the World Ocean, as simulated by NorCPM1. I start with an example from the Barents Sea, where we have found two specific events of positive phytoplankton anomalies to be predictable up to five years ahead. In the seasonal ice covered region, the predictability comes as a result of an anomalous heat transport from the Subpolar North Atlantic, resulting in a reduced ice cover which promotes phytoplankton growth. In the southern, ice free domain, the predictability comes as a result of nutrient advection from the Subpolar North Atlantic, also resulting in higher primary production. The nutrient and heat anomalies show a temporal shift, and we relate them to periods of retraction and expansions, separately, of the North Atlantic Subpolar Gyre.

After the Barents Sea example, I will move into other parts of the World Ocean, comparing NorCPM1 simulations to observational data, and discussing potential reasons behind phytoplankton (un)predictability.