Net community production in the deep euphotic zone of the subtropical North Pacific gyre from glider surveys

Abstract

Seagliders, deployed through most of 2005 in the subtropical North Pacific gyre, made measurements of temperature, salinity, and dissolved oxygen to quantify net community production (NCP) at Station A LongTerm Oligotrophic Habitat Assessment (ALOHA) of the Hawaii Ocean Time-series (HOT) using an oxygen mass balance approach. A 'bowtie'-shaped pattern, 50 km by 50 km in size was repeatedly traversed at two week intervals with the goal of observing the influence of Rossby waves and eddies on the productivity of the study region. Rossby waves and eddies in the region cause a vertical displacement of isopycnal depth of ,650 m at the base of the euphotic zone. Shoaling of isopycnals is demonstrated to drive productivity in the deep euphotic zone. Four mesoscale shoaling events were observed between February and November in 2005. During each event when isopycnals shoaled, oxygen concentrations on isopycnals increased, fluorescence in the deep euphotic zone was higher, and net community production was elevated. Productivity in the deep euphotic zone was strongly influenced by Rossby waves and eddies, but this influence was not observed to extend into the mixed layer.

The role of net community production in air‐sea carbon fluxes at the North Pacific subarctic‐subtropical boundary region

“…Thus, biological oxygen production in the deeper reservoir is, if anything, an underestimate. At the Hawaii Ocean Time-series, the error induced by assuming low vertical mixing may leave up to 40% of submixed-layer production unaccounted for (Hamme and Emerson 2006;Nicholson et al 2008). Previous estimates of the depth distribution of oxygen production at Sta.…”

“…Previous estimates of the depth distribution of oxygen production at Sta. ALOHA indicate production in the mixed layer accounts for 70-80% of the NCP Nicholson et al 2008). Table 1.…”

Gliders as a Component of Future Observing Systems

“…, Gary Meyers (2) , Chari Pattiaratchi (3) , Ralf Bachmayer (4) , Dan Hayes (5) , Sylvie Pouliquen (6) , Loic Petit de la Villeon (6) , Thierry Carval (6) , Alexandre Ganachaud (7) , Lionel Gourdeau (7) , Laurent Mortier (8) , Hervé Claustre (9) , Vincent Taillandier (9) , Pascale Lherminier (10) , Thierry Terre (10) , Martin Visbeck (11) , Johannes Karstensen (11) , Gerd Krahmann (11) , Alberto Alvarez (12) , Michel Rixen (12) , Pierre-Marie Poulain (13) , Svein Osterhus (14) , Joaquin Tintore (15) , Simon Ruiz (15) , Bartolomeo Garau (15) , David Smeed (16) , Gwyn Griffiths (16) , Lucas Merckelbach (16) , Toby Sherwin (17) , Claudia Schmid (18) , John A. Barth (19) , Oscar Schofield ( (23) SIO …”

Deployments in extreme conditions: Pushing the boundaries of Seaglider capabilities

“…Gliders have repeatedly demonstrated their capabilities in process studies; however, their use in persistent observatories is only just beginning despite [2]- [10]. This is likely due to the remaining uncertainty around the technology.…”