Chemical characteristics of water masses in the Rockall Trough

• Published in: Deep Sea Research Part I: Oceanographic Research Papers
• Main Authors: McGrath, Triona, Nolan, Glenn, McGovern, Evin
• Format: Article in Journal/Newspaper
• Language: English
• Published: Elsevier 2011
• Subjects: Water masses; Nutrients; Oxygen; Salinity; Rockall Trough; North Atlantic; Arctic; Labrador Sea; north atlantic current
• Online Access: http://hdl.handle.net/10793/711; https://doi.org/10.1016/j.dsr.2011.11.007

NOTICE: this is the author’s version of a work that was accepted for publication in Deep Sea Research Part I: Oceanographic Research Papers. Changes resulting from the publishing process, such as peer review, editing, corrections, structural formatting, and other quality control mechanisms may not be reflected in this document. Changes may have been made to this work since it was submitted for publication. A definitive version was subsequently published in Deep Sea Research Part I: Oceanographic Research Papers, [In Press (December 2011)] doi:10.1016/j.dsr.2011.11.007 http://www.sciencedirect.com/science/article/pii/S0967063711002111 peer-reviewed Direct observations of physical and chemical data in the Rockall Trough during February of 2008, 2009 and 2010 are presented. Results are compared to a similar WOCE transect, AR24, completed in November/December 1996. Temperature and salinity data have been used to identify the water masses present in the Trough, and have been combined with nutrient (nitrate, nitrite, phosphate, silicate) and oxygen data to produce a table outlining the chemical characteristics of each of the water masses. Eastern North Atlantic Water (ENAW) moving north through the Trough gains nutrients from a branch of the North Atlantic Current (NAC). Mediterranean Water (MW) was identified as a warm saline core, with characteristically low oxygen and low preformed nutrients along the Irish continental shelf break near 53°N. Found at a similar density level at the southern entrance to the Trough, Sub Arctic Intermediate Water (SAIW) has relatively high oxygen and preformed nutrients, likely entrained from the subpolar gyre when it was formed. LSW was identified as a prominent water mass between 1500–2000 m deep, with characteristically high oxygen content. Lower silicate, and to a lesser extent preformed nitrate, in 2009 coincide with a freshening of Labrador Sea Water (LSW) relative to other years, and could indicate a stronger influence from the Labrador Current when it was formed. Finally, ...