From silk to satellite: half a century of ocean colour anomalies in the Northeast Atlantic

• Published in: Global Change Biology
• Main Authors: Raitsos, DE, Pradhan, Y, Lavender, SJ, Hoteit, I, McQuatters-Gollop, A, Reid, PC, Richardson, AJ
• Format: Article in Journal/Newspaper
• Language: unknown
• Published: 2014
• Subjects: Ecology and Environment; Marine Sciences; Northeast Atlantic
• Online Access: http://plymsea.ac.uk/id/eprint/5899/; http://onlinelibrary.wiley.com/doi/10.1111/gcb.12457/abstract; https://doi.org/10.1111/gcb.12457

Changes in phytoplankton dynamics influence marine biogeochemical cycles, climate processes, and food webs, with substantial social and economic consequences. Large-scale estimation of phytoplankton biomass was possible via ocean colour measurements from two remote sensing satellites – the Coastal Zone Color Scanner (CZCS, 1979-1986) and the Sea-viewing Wide Field-of-view Sensor (SeaWiFS, 1998-2010). Due to the large gap between the two satellite eras and differences in sensor characteristics, comparison of the absolute values retrieved from the two instruments remains challenging. Using a unique in situ ocean colour dataset that spans more than half a century, the two satellite-derived chlorophyll-a (Chl-a) eras are linked to assess concurrent changes in phytoplankton variability and bloom timing over the Northeast Atlantic Ocean and North Sea. Results from this unique re-analysis reflect a clear increasing pattern of Chl-a, a merging of the two seasonal phytoplankton blooms producing a longer growing season and higher seasonal biomass, since the mid-1980s. The broader climate plays a key role in Chl-a variability as the ocean colour anomalies parallel the oscillations of the Northern Hemisphere Temperature (NHT) since 1948.