Unusual subpolar North Atlantic phytoplankton bloom in 2010: Volcanic fertilization or North Atlantic Oscillation?
Article first published online: 1 OCT 2013
©2013. American Geophysical Union. All Rights Reserved.
Journal of Geophysical Research: Oceans
Volume 118, Issue 10, pages 4771–4780, October 2013
How to Cite
2013), Unusual subpolar North Atlantic phytoplankton bloom in 2010: Volcanic fertilization or North Atlantic Oscillation?, J. Geophys. Res. Oceans, 118, 4771–4780, doi:10.1002/jgrc.20363., , , , and (
- Issue published online: 26 NOV 2013
- Article first published online: 1 OCT 2013
- Accepted manuscript online: 24 AUG 2013 01:24AM EST
- Manuscript Revised: 15 AUG 2013
- Manuscript Accepted: 15 AUG 2013
- Manuscript Received: 26 FEB 2013
- satellite ocean color;
- spring bloom;
- interannual variability;
- freshwater anomaly
 In summer and autumn 2010, a highly anomalous phytoplankton bloom, with chlorophyll concentration more than double that of previous years, was observed in the Irminger Basin, southwest of Iceland. Two unusual events occurred during 2010 which had the potential to promote the unusual bloom. First, in spring 2010, the Eyjafjallajökull volcano in Iceland erupted, depositing large quantities of tephra into the subpolar North Atlantic. Second, during the winter of 2009/2010 the North Atlantic Oscillation (NAO) became extremely negative, developing into the second strongest negative NAO on record. Hydrographic conditions were highly anomalous in the region, with an influx of freshwater spreading through the basin, and unusual nutrient and mixed layer depth conditions. Here we use a combination of satellite, modeled and in situ data to investigate whether the input of iron from the volcanic eruption or change in hydrographic conditions due to the extreme negative NAO were responsible for the anomalous phytoplankton bloom. We conclude that changes in physical forcing driven by the NAO, and not the volcanic eruption, stimulated the unusual bloom.