Abstract
<p> <p id="x-x-sp0100"> As part of an effort to monitor changes in inorganic carbon chemistry of the coastal ocean, near-synoptic cruises are being conducted in the Northern Gulf of Mexico and along the East Coast of the United States. Here we describe observations obtained on a cruise in the summer of 2012 and compare them with results from a cruise following a similar track in 2007. The focus is on describing spatial patterns of aragonite saturation state ( <em> Ω </em> <sub> Ar </sub> ). This parameter is an indicator of ecosystem health, in particular for calcifying organisms. The results show large-scale regional trends from different source waters at the northeastern and southwestern edges of the domain, along with the modulating effects of remineralization/respiration and riverine inputs. The broader patterns and changes over five years along the coast can be well described by the impacts of large-scale circulation, notably changes in source water contributions. Changes in the well-buffered Loop Current and Gulf Stream with high <em> Ω </em> <sub> Ar </sub> impact the waters in the southern part of the study area. The less buffered southward coastal currents with low <em> Ω </em> <sub> Ar </sub> originating from the Labrador Sea and Gulf of St. Lawrence impact the <em> Ω </em> <sub> Ar </sub> patterns in the Northern regions. The expected 2% average decrease in <em> Ω </em> <sub> Ar </sub> in the surface mixed layer due to increasing atmospheric CO <sub> 2 </sub> levels over the 5-year period is largely overshadowed by local and regional variability from changes in hydrography and mixed layer dynamics. </p></p>
Original language | American English |
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Journal | Continental Shelf Research |
Volume | 98 |
DOIs | |
State | Published - Jan 1 2015 |
Keywords
- Ocean acidification
- Inorganic carbon system
- Coastal ocean
- Northern Gulf of Mexico
- East Coast
Disciplines
- Life Sciences