ABSTRACT
Existing aquatic circulation models are designed for large, basin-size scales and therefore cannot resolve the planktic organism scales of A-H balance. ›e nonlinear kinetics of biological responses to physical and chemical variables are more appropriately described at micro-scales, at the level of molecular di§usion. It is striking to realize that typical computation grids in 3D numerical models for lakes and oceans are more than 106 times largerthanthedimensionsofplankticorganisms.›erefore, thereisamajordi§erencebetweenthetypicalcomputational gridscalewithassociatedscaleofresolvedžuidmotionsand themajorityofphytoplanktonandbacteria.Further,bothžuid motionsandcategoriesofplanktonhavesigniŸcanttemporal andspatialheterogeneitiesinaquaticecosystems(Durhametal. 2009;WüestandLorke2009).Towhatextentdophysicaland chemicalprocessesguideformation,location,anddurationof suchheterogeneities?Howdoindividualorganisms“feel”the physicalenvironmentastheyrespondtoit?Parameterizationfor smallerscalesisthereforenecessary,andthereisanurgentneed formodelingA-Hprocessesatscalesthataremuchsmallerthan those addressed by existing aquatic circulation models.
