Record Details
Seasonal cycle of surface ocean pCO₂ on the Oregon shelf
ScholarsArchive at Oregon State University
| Field | Value |
|---|---|
| Title | Seasonal cycle of surface ocean pCO₂ on the Oregon shelf |
| Names |
Evans, Wiley
(creator) Hales, Burke (creator) Strutton, Peter G. (creator) |
| Date Issued | 2011-05-20 (iso8601) |
| Note | This is the publisher's final pdf. The published article is copyrighted by American Geophysical Union and can be found at: http://www.agu.org/journals/jc/. |
| Abstract | Previous work has shown that the Oregon shelf is a sink for atmospheric carbon dioxide (CO₂) during the upwelling season; however, until now, summertime variability in CO₂ exchange and sign of the flux for the rest of the year were unknown. Observations of the partial pressure of CO₂ (pCO₂) in surface waters from August 2007 to May 2010 from ships and a buoy were used with historical data to produce a composite seasonal cycle for the central Oregon midshelf. These data indicate that the region is highly variable, at times being either a sink or strong source for atmospheric CO₂. Interannual wind variability was an important determining factor in shaping the sink/source nature of this system. Late summer and early autumn was most variable relative to the rest of the year. Winter pCO₂ was near or slightly below atmospheric levels. Strong shelf-wide undersaturated conditions were first observed in early spring and lasted until the upwelling season became developed. Peak upwelling season pCO₂ ranged from <200 μatm to >1000 μatm. In July 2008, ship and buoy data revealed previously unobserved high-pCO₂ waters (∼1000 μatm) at the surface. These conditions persisted for nearly 2 months and drove this system to be only a weak net annual atmospheric CO₂ sink of −0.3 ± 6.8 mol m⁻² yr⁻¹. These data showed, for the first time, the seasonal cycle of surface ocean pCO₂ on the central Oregon midshelf and the impact of heretofore undocumented pCO₂ levels on an estimate of sea-air CO₂ flux for this region. |
| Genre | Article |
| Identifier | Evans, W., B. Hales, and P. G. Strutton (2011), Seasonal cycle of surface ocean pCO₂ on the Oregon shelf, Journal of Geophysical Research, 116, C05012, doi:10.1029/2010JC006625. |
