Potential Predictability of the Spring Bloom in the Southern Ocean Sea Ice Zone

• Published in: Geophysical Research Letters
• Main Authors: Benjamin Buchovecky, Graeme A. MacGilchrist, Mitchell Bushuk, F. Alexander Haumann, Thomas L. Frölicher, Natacha Le Grix, John Dunne
• Format: Article in Journal/Newspaper
• Language: English
• Published: Wiley 2023
• Subjects: Geophysics. Cosmic physics; QC801-809; Antarc*; Antarctic; Sea ice; Southern Ocean
• Online Access: https://doi.org/10.1029/2023GL105139; https://doaj.org/article/7f9e9e1bfb5643b4834eb35605b5f7fc

Abstract Every austral spring when Antarctic sea ice melts, favorable growing conditions lead to an intense phytoplankton bloom, which supports much of the local marine ecosystem. Recent studies have found that Antarctic sea ice is predictable several years in advance, suggesting that the spring bloom might exhibit similar predictability. Using a suite of perfect model predictability experiments, we find that November net primary production (NPP) is potentially predictable 7 to 10 years in advance in many Southern Ocean regions. Sea ice extent predictability peaks in late winter, followed by absorbed shortwave radiation and NPP with a 2 to 3 months lag. This seasonal progression of predictability supports our hypothesis that sea ice and light limitation control the inherent predictability of the spring bloom. Our results suggest skillful interannual predictions of NPP may be achievable, with implications for managing fisheries and the marine ecosystem, and guiding conservation policy in the Southern Ocean.