Abstract
The Salish Sea, spanning Washington State and British Columbia, receives relatively low pH water from upwelling in the northeast Pacific Ocean and the acidity of bottom water increases within the sea, particularly in winter. In order to better understand the processes that lead to bottom water acidification in this region, I quantified the sources of dissolved inorganic carbon (DIC) and alkalinity to bottom water in Bellingham Bay, a small embayment that is nevertheless representative of the broader Salish Sea. Corrosive bottom water with a pH of 7.5 and an aragonite saturation state of 0.51 was observed in deep water the northern portion of the bay. Water column respiration contributed 6.8 mmol DIC m−3 d−1 to bottom water while sediments added both DIC (13.6 mmol m−2 d−1) and alkalinity (9 mmol m−2 d−1). A two-layer box model assessed the relative importance of sources of corrosive water to the bay and calculated how bottom water pH and aragonite saturation state vary during spring. The 30-day model run calculated increases in bottom water DIC and alkalinity but decreases in bottom water pH and aragonite saturation state along with oscillations of these parameters with a period of approximately 6 days. A sensitivity analysis of the model demonstrated that water column respiration was the primary driver of corrosive bottom-water production. Sediment respiration contributed less to the production of corrosive water but was a source of alkalinity. The accumulation of corrosive bottom water in Bellingham Bay was also a function of mean circulation; the slowing of bottom water flow led to longer bottom-water residence time and an increase in bottom water corrosivity.
Similar content being viewed by others
References
Anderson, S.W., and E.E. Grossman. 2017. Topographic and bathymetric elevation data for the Nooksack River, Fall 2015: U.S. Geological Survey Data Release. https://doi.org/10.5066/F72B8W7M.
Babson, A.L., M. Kawase, and P. MacCready. 2006. Seasonal and interannual variability in the circulation of Puget Sound, Washington: a box model study. Atmosphere-Ocean 44 (1): 29–45.
Barnes, C.A., and E.E. Collias. 1961. Some considerations of oxygen utilization rates in Puget Sound. Journal of Marine Research 17: 68–80.
Beckwith, S.T., R.H. Byrne, and P. Hallock. 2019. Riverine calcium end-members improve coastal saturation state calculations and reveal regionally variable calcification potential. Frontiers in Marine Science 6: 169.
Burdige, D.J. 2006. Geochemistry of marine sediments, 609. Princeton: Princeton University Press.
Cai, W.J., and Y. Wang. 1998. The chemistry, fluxes, and sources of carbon dioxide in the estuarine waters of the Satilla and Altamaha Rivers, Georgia. Limnology and Oceanography 43 (4): 657–668.
Cai, W.J., X. Hu, W.J. Huang, M.C. Murrell, J.C. Lehrter, S.E. Lohrenz, W.C. Chou, W. Zhai, J.T. Hollibaugh, Y. Wang, P. Zhao, X. Guo, K. Gundersen, M. Dai, and G.C. Gong. 2011. Acidification of subsurface coastal waters enhanced by eutrophication. Nature Geoscience 4 (11): 766–770.
Cai, W.J., W.J. Huang, G.W. Luther, D. Pierrot, M. Li, J. Testa, J.M. Xue, A. Joesoef, R. Mann, J. Brodeur, and Y.Y. Xu. 2017. Redox reactions and weak buffering capacity lead to acidification in the Chesapeake Bay. Nature Communications 8 (1): s41467–s41417. https://doi.org/10.1038/s41467-017-00417-7.
Chen, C.A., H. Lui, C. Hsieh, T. Yanagi, N. Kosugi, M. Ishii, and G. Gong. 2017. Deep oceans may acidify faster than anticipated due to global warming. Nature Climate Change 7 (12): 890–894.
Christensen, J.P., and T.T. Packard. 1976. Respiratory electron transport activities in phytoplankton and bacteria: comparison of methods. Limnology and Oceanography 24: 576–583.
Clayton, T.D., and R.H. Byrne. 1993. Spectrophotometric seawater pH measurements: total hydrogen ion concentration scale calibration of m-cresol purple and at-sea results. Deep Sea Research Part I: Oceanographic Research Papers 40 (10): 2115–2129.
Dickson, A.G. 1981. An exact definition of total alkalinity and a procedure for the estimation of alkalinity and total inorganic carbon from titration data. Deep-Sea Research 28A: 609–623.
Doney, S.C., V.J. Fabry, R.A. Feely, and J.A. Kleypas. 2009. Ocean acidification: the other CO2 problem. Annual Review of Marine Science 1 (1): 169–192.
Dyer, K.R. 1991. Circulation and mixing in stratified estuaries. Marine Chemistry 32 (2-4): 111–120.
Fassbender, A.J., S.R. Alin, R.A. Feely, A.J. Sutton, J.A. Newton, C. Krembs, J. Bos, M. Keyzers, A.H. Devol, W. Ruef, and G. Pelletier. 2018. Seasonal carbonate chemistry variability in marine surface waters of the US Pacific Northwest. Earth System Science Data 10 (3): 1367–1401. https://doi.org/10.5194/essd-10-1367-2018.
Feely, R.A., C.L. Sabine, K. Lee, W. Berelson, J. Kleypas, V.J. Fabry, and F.J. Millero. 2004. Impact of anthropogenic CO on the CaCO system in the oceans. Science 305: 362–366.
Feely, R.A., C.L. Sabine, J.M. Hernandez-Ayon, D. Ianson, and B. Hales. 2008. Evidence for upwelling of corrosive“ acidified” water onto the continental shelf. Science 320 (5882): 1490–1492.
Feely, R.A., S.R. Alin, J. Newton, C.L. Sabine, M. Warner, A. Devol, C. Krembs, and C. Maloy. 2010. The combined effects of ocean acidification, mixing, and respiration on pH and carbonate saturation in an urbanized estuary. Estuarine, Coastal and Shelf Science 88 (4): 442–449.
Feely, R.A., T. Klinger, J.A. Newton, and M. Chadsey. 2012. Scientific summary of ocean acidification in Washington State marine waters. NOAA OAR Special Report.
Forja, J.M., J. Blasco, and A. Gómez-Parra. 1994. Spatial and seasonal variation of in situ benthic fluxes in the Bay of Cadiz (South-west Spain). Estuarine, Coastal and Shelf Science 39 (2): 127–141.
Giblin, A.E., C.S. Hopkinson, and J. Tucker. 1997. Benthic metabolism and nutrient cycling in Boston Harbor, Massachusetts. Estuaries 20 (2): 346–364.
Hagens, M., C. Slomp, F. Meysman, D. Seitaj, J. Harlay, A. Borges, and J. Middelburg. 2015. Biogeochemical processes and buffering capacity concurrently affect acidification in a seasonally hypoxic coastal marine basin. Biogeosciences 12 (5): 1561–1583.
Hu, X. and W.J. Cai. 2011. An assessment of ocean margin anaerobic processes on oceanic alkalinity budget. Global Biogeochemical Cycles 25(3): GB3003. https://doi.org/10.1029/2010GB003859.
Jiang, L.Q., W.J. Cai, R.A. Feely, Y. Wang, X. Guo, D.K. Gledhill, X. Hu, F. Arzayus, F. Chen, J. Hartmann, and L. Zhang. 2010. Carbonate mineral saturation states along the US East Coast. Limnology and Oceanography 55 (6): 2424–2432.
Kortzinger, A., J.I. Hedges, and P.D. Quay. 2001. Redfield ratios revisited: Removing the biasing effect of anthropogenic CO2. Limnology and Oceanography 46 (4): 964–970.
Krumins, V., M. Gehlen, S. Arndt, P. Van Cappellen, and P. Regnier. 2013. Dissolved inorganic carbon and alkalinity fluxes from coastal marine sediments: model estimates for different shelf environments and sensitivity to global change. Biogeosciences 10: 371–398.
Lowe, A.T., J. Bos, and J. Ruesink. 2019. Ecosystem metabolism drives pH variability and modulates long-term ocean acidification in the Northeast Pacific coastal ocean. Scientific Reports 9: 1–11.
Long, W., T. Khangaonkar, M. Roberts and G. Pelletier. 2014. Approach for simulating acidification and the carbon cycle in the Salish Sea to distinguish regional source impacts. Washington State Department of Ecology Pub. No. 14-03-002.
Millero, F.J. 1979. The thermodynamics of the carbonate system in seawater. Geochimica et Cosmochimica Acta 43: 1651–1661.
Millero, F.J. 2010. Carbonate constants for estuarine waters. Marine and Freshwater Research 61 (2): 139–142.
Nesbitt, E.A., R.A. Martin, D.E. Martin, and J. Apple. 2015. Rapid deterioration of sediment surface habitats in Bellingham Bay, Washington State, as indicated by benthic foraminifera. Marine Pollution Bulletin 97: 273–284.
Pierrot, D., E. Lewis, and D.W.R. Wallace. 2006. MS Excel program developed for CO2 system calculations. ORNL/CDIAC-105a. Carbon Dioxide Information Analysis Center, Oak Ridge National Laboratory, U.S. Department of Energy, Oak Ridge, Tennessee. doi: https://doi.org/10.3334/CDIAC/otg.CO2SYS_XLS_CDIAC105a
Riley, J.P., and M. Tongudai. 1967. The major cation/chlorinity ratios in sea water. Chemical Geology 2: 263–269.
Salisbury, J., M. Green, C. Hunt, and J. Campbell. 2008. Coastal acidification by rivers: a threat to shellfish? EOS 89 (50): 513–528.
Sunda, W.G., and W.J. Cai. 2012. Eutrophication induced CO2-acidification of subsurface coastal waters: interactive effects of temperature, salinity, and atmospheric pCO2. Environmental Science & Technology 46 (19): 10651–10659.
Wallace, R.B., H. Baumann, J.S. Grear, R.C. Aller, and C.J. Gobler. 2014. Coastal ocean acidification: the other eutrophication problem. Estuarine, Coastal and Shelf Science 148: 1–13.
Wang, T., and Z. Yang. 2015. Understanding the flushing capability of Bellingham Bay and its implication on bottom water hypoxia. Estuarine, Coastal and Shelf Science 165: 279–290.
Wolf-Gladrow, D.A., R.E. Zeebe, C. Klaas, A. Körtzinger, and A.G. Dickson. 2007. Total alkalinity: the explicit conservative expression and its application to biogeochemical processes. Marine Chemistry 106 (1-2): 287–300.
Xue, L., and W. Cai. 2020. Total alkalinity minus dissolved inorganic carbon as a proxy for deciphering ocean acidification mechanisms. Marine Chemistry 222: 103791. https://doi.org/10.1016/j.marchem.2020.103791.
Acknowledgments
This study was conducted as part of an undergraduate course, Oceanography of the Salish Sea. The following students assisted with this project. Hydrographic survey: Nick Sturman, Cecily Ofstad, and Kristen Fagerstrom. Sediment fluxes: Zach Barker, Nick Bartish, Kaya Fletcher, and Stephan Neu-Yagle. Data analysis and running of an early-version box model: Alice Lazzar-Atwood, Gina O’Kelley, and Nilza Sonam. Water column respiration: Kastin Ellis, Jackson Osborn, and Lauchlan Ray. Nooksack River sampling: Nick Tedford, Talulah Schultz, and Benjamen Smith. I am also grateful to Kelly Bright for supervising the measurement of DIC and pH and to Brooke Love for providing advice and instrumentation that enabled my class to complete this project. I thank Beth Curry (UW-APL) for help with the time-series data from the Se’lhaem buoy and for her assistance with pH sensor corrections. Comments from two anonymous reviewers improved the manuscript. I am responsible for the content of this paper including any errors, but I greatly appreciate the assistance of so many students and colleagues.
Author information
Authors and Affiliations
Corresponding author
Additional information
Communicated by Lijun Hou
Rights and permissions
About this article
Cite this article
Shull, D.H. Sources of Corrosive Bottom Water to Bellingham Bay, Washington State. Estuaries and Coasts 44, 1250–1261 (2021). https://doi.org/10.1007/s12237-020-00859-1
Received:
Revised:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1007/s12237-020-00859-1