Publications

Li, ZC; Cassar, N; Huang, K; Ducklow, H; Schofield, O (2016). Interannual variability in net community production at the Western Antarctic Peninsula region (1997-2014). JOURNAL OF GEOPHYSICAL RESEARCH-OCEANS, 121(7), 4748-4762.

Abstract
In this study, we examined the interannual variability of net community production (NCP) in the Western Antarctic Peninsula (WAP) using in situ O-2/Ar-NCP estimates (2008-2014) and satellite data (SeaWiFS and MODIS-Aqua) from 1997 to 2014. We found that NCP generally first peaks offshore and follows sea-ice retreat from offshore to inshore. Annually integrated NCP (ANCP) displays an onshore-to-offshore gradient, with coastal and shelf regions up to 8 times more productive than offshore regions. We examined potential drivers of interannual variability in the ANCP using an Empirical Orthogonal Function (EOF) analysis. The EOF's first mode explains approximate to 50% of the variance, with high interannual variability observed seaward of the shelf break. The first principal component is significantly correlated with the day of sea-ice retreat (R=-0.58, p<0.05), as well as the Southern Annular Mode (SAM) and El Nino Southern Oscillation (ENSO) climate indices in austral spring. Although the most obvious pathway by which the day of sea-ice retreat influences NCP is by controlling light availability early in the growing season, we found that the effect of day of sea-ice retreat on NCP persists throughout the growing season, suggesting that additional controls, such as iron availability, are preconditioned or correlated to the day of sea-ice retreat.

DOI:
10.1002/2015JC011378

ISSN:
2169-9275