Extended Data Fig. 2: Seasonal evolution of excess ligands.
From: Authigenic mineral phases as a driver of the upper-ocean iron cycle
Observed and modelled excess total (black symbols) and strong (red symbols) ligands (both in nM). Solid and dashed black lines are model solutions at the BATS site from the PISCES-Quota model, with varying total ligands derived from DOC (using 0.09, 0.08 and 0.07 nM LT (µM DOC)−1) or prognostic stronger ligands (thin black lines). Blue lines represent model solutions from PISCES-Quota-Fe, with either prognostic stronger ligands (solid line) or DOC-derived total ligands (dashed line, using 0.09 nM LT (µM DOC)−1). Values less than zero are when DFe concentrations exceed the concentrations of either L1 or LT. Only the PISCES-Quota-Fe model is able to generate the observed large excess ligand pools.
