Nutrient enrichment of the subarctic Pacific Ocean pycnocline
Article first published online: 30 MAY 2013
©2013. American Geophysical Union. All Rights Reserved.
Geophysical Research Letters
Volume 40, Issue 10, pages 2200–2205, 28 May 2013
How to Cite
2013), Nutrient enrichment of the subarctic Pacific Ocean pycnocline, Geophys. Res. Lett., 40, 2200–2205, doi:10.1002/grl.50439., , and (
- Issue published online: 1 JUL 2013
- Article first published online: 30 MAY 2013
- Accepted manuscript online: 3 APR 2013 12:00AM EST
- Manuscript Accepted: 31 MAR 2013
- Manuscript Received: 11 MAR 2013
- nutrient cycling;
- oxygen transport;
- subarctic Pacific
 At the end of the global thermohaline circulation, the subarctic Pacific is the richest nutrient repository in the world oceans. Trends towards lower oxygen and higher nutrients in waters below the surface layer (the pycnocline) have been observed in recent decades. We assess these trends using data from four programs and suggest the enrichment of pycnocline nitrate (200 Gmol y−1) is essential in keeping supply to the surface ocean constant, despite increasing upper ocean stratification. A nitrate budget helps identify possible vertical processes that could account for nutrient redistribution. We hypothesize that warming and oxygen loss in the deeper pycnocline, arising from ice loss in the Okhotsk Sea, have initiated a largely vertical redistribution of nutrients due to compression of vertical migrator habitat and/or changes in dissolution of sinking particulates. Coupled climate-ecosystem models will need to incorporate these processes to more fully understand projected changes in the subarctic Pacific.