POSTER SESSION 3
15:30–17:30, Wednesday, September 16
Poster Session | 1 | 2 | 3 | 4 | Schedule at a Glance
ABSTRACT 1091 | POSTER 195
DIAGNOSING ALGORITHM DIVERGENCE TO UNDERSTAND RISING SUBSURFACE OCEAN PRODUCTIVITY AT STATION ALOHA
Net primary production (NPP) can be estimated with ocean-colour remote sensing using chlorophyll, but that relationship to phytoplankton carbon and light absorption itself varies with depth and physiology. At Station ALOHA (Hawaii Ocean Time-series), three decades of bottle-incubation measurements show a significant NPP increase, while surface NPP and chlorophyll stay flat, rising only near the deep chlorophyll maximum. Three widely used ocean-colour NPP algorithms, driven by the same satellite record, instead show a significant decline over the same period, opposite in sign to the in situ trend. Rather than treat this mismatch as noise, we use it diagnostically, asking which optical assumptions in each algorithm break down with depth, and why. Models that infer production directly from light absorption, rather than from a modelled chlorophyll-to-carbon relationship, come closest to the in situ magnitude, consistent with chlorophyll being confounded by photoacclimation. As warming strengthens stratification, accounting for this subsurface gain, not just surface metrics, will be essential to projecting future carbon export and the biological pump.
Clara Rodriguez Vives, GESTAR II, NASA Goddard Space Flight Center, [email protected], https://orcid.org/0000-0002-6150-7644
Hanani Adiwira, WPI-AIMEC, Tohoku University, [email protected]
Angelique White, University of Hawaii Manoa, [email protected]
Johannes Viljoen, University of Exeter, [email protected]
Michael Behrenfeld, Oregon State University, [email protected]
Poster Session | 1 | 2 | 3 | 4 | Schedule at a Glance
