Perspectives
on modeling and prediction
by
John Dunne
History of coupled biological-physical model development
"Phytoplankton functional groups:"
Phytoplankton functional groups: | ||
Size partitioning | ||
Variable stoichiometry | ||
Mesoscale nutrient supply | ||
Physical and temporal patchiness | ||
Twilight zone | ||
CaCO3 cycling | ||
Mineral ballasting | ||
Complex role of iron as a limiting nutrient | ||
Transport of organic matter |
Increased sophistication of satellite algorithms | ||
Addition of phytoplankton functional groups | ||
Addition of elements | ||
Increased realism of physical models | ||
Spatial resolution (mesoscale eddies) | ||
Temporal variability (El Nino; NAO; PDO) | ||
Better physics (Gent-McWilliams; KPP) | ||
Distinguishing regions of nitrogen, phosphorus, silicon and iron limitation |
Global Modeling of functional Groups
Excess density required to sink (Smayda, 1970) | ||
Diatoms sink readily (compared to picoplankton) | ||
Recently, that CaCO3 is necessary to sink deeply | ||
Sinking SiO2 carries 2.6 % by weight Org. C. while CaCO3 carries 7 % (Klaas and Archer, in prep.) | ||
SiO2 sinks more slowly than CaCO3 (Berelson) | ||
SiO2 remineralizes more shallowly than CaCO3 | ||
(ZSiO2 ~1000 m vs. ZCaCO3 ~2500 m) |
Provinces of Nutrient Limitation
Biological Feedbacks on Circulation
Q1: What has been the major contribution of JGOFS to ocean biogeochemical modeling?
Q2: What has been the major change in thought since the SMP Implementation Plan?
Q3: What is the most pressing uncertainty in biogeochemical modeling?