On the drivers of phytoplankton blooms in the Antarctic seasonal ice zone: A GCM approach

• Main Authors: Taylor, Marc, Losch, Martin, Bracher, Astrid
• Format: Conference Object
• Language: unknown
• Published: 2012
• Subjects: Antarctic; The Antarctic; Antarc*; Sea ice
• Online Access: https://epic.awi.de/id/eprint/25972/; https://epic.awi.de/id/eprint/25972/1/Taylor_etal_2012_Poster_Ocean_Sciences_Meeting.pdf; https://hdl.handle.net/10013/epic.38936; https://hdl.handle.net/10013/epic.38936.d001

The Antarctic seasonal ice zone (SIZ) has been found to support spring phytoplankton blooms on orders of magnitude greater than in neighboring open ocean waters. Blooms are known to begin as soon as the ice begins to deteriorate and are hypothesized to occur when melting sea ice creates a shallow, stable pycnocline where phytoplankton communities can develop in the high-light, high-nutrient conditions. Due to the difficulties in observing the blooms in situ or remotely, we use a high resolution (18 km ave. grid length) bio-physically coupled global circulation model (GCM) to test this hypothesis. Study areas of the SIZ were identified through correlation of model output with remote sensing estimates of sea surface temperature, sea ice concentration and chlorophyll a concentration. A Generalized Additive Model was used to assess the importance of various modeled parameters on phytoplankton dynamics. Initial results support the hypothesis that physical conditions drive blooms dynamics while nutrient limitation is of lesser importance.