Oceanography The Official Magazine of
The Oceanography Society
Volume 31 Issue 01

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Volume 31, No. 1
Pages 60 - 70

The Changing Nature of Shelf-Break Exchange Revealed by the OOI Pioneer Array

Glen Gawarkiewicz Robert E. ToddWeifeng ZhangJacob PartidaAvijit GangopadhyayMahmud-Ul-Hasan MonimPaula FratantoniAnna Malek MercerMargaret Dent
Article Abstract

Although the continental shelf and slope south of New England have been the subject of recent studies that address decadal-scale warming and interannual variability of water mass properties, it is not well understood how these changes affect shelf-break exchange processes. In recent years, observations of anomalous shelf and slope conditions obtained from the Ocean Observatories Initiative Pioneer Array and other regional observing programs suggest that onshore intrusions of warm, salty waters are becoming more prevalent. Mean cross-shelf transects constructed from Pioneer Array glider observations collected from April 2014 through December 2016 indicate that slope waters have been warmer and saltier. We examine shelf-break exchange events and anomalous onshore intrusions of warm, salty water associated with warm core rings located near the shelf break in spring 2014 and winter 2017 using observations from the Pioneer Array and other sources. We also describe an additional cross-shelf intrusion of ring water in September 2014 to demonstrate that the occurrence of high-salinity waters extending across the continental shelf is rare. Observations from the Pioneer Array and other sources show warm core ring and Gulf Stream water masses intrude onto the continental shelf more frequently and penetrate further onshore than in previous decades.

Citation

Gawarkiewicz, G., R.E. Todd, W. Zhang, J. Partida, A. Gangopadhyay, M.-U.-H. Monim, P. Fratantoni, A. Malek Mercer, and M. Dent. 2018. The changing nature of shelf-break exchange revealed by the OOI Pioneer Array. Oceanography 31(1):60–70, https://doi.org/10.5670/oceanog.2018.110.

References

Andres, M. 2016. On the recent destabilization of the Gulf Stream path downstream of Cape Hatteras. Geophysical Research Letters 43:9,836–9,842, https://doi.org/10.1002/2016GL069966.

Bell, R.J., J.A. Hare, J.P. Manderson, and D.E. Richardson. 2014. Externally driven changes in the abundance of summer and winter flounder. ICES Journal of Marine Science 71(9):2,416–2,428, https://doi.org/10.1093/icesjms/fsu069.

Cenedese, C., R.E. Todd, G. Gawarkiewicz, and A. Shcherbina. 2013. Offshore transport of shelf water through interaction of vortices with a shelfbreak current. Journal of Physical Oceanography 43:905–919, https://doi.org/10.1175/JPO-D-12-0150.1.

Chaudhuri, A.H., A. Gangopadhyay, and J.J. Bisagni. 2009. Interannual variability of Gulf Stream warm core rings in response to the North Atlantic Oscillation. Continental Shelf Research 29:856–869, https://doi.org/10.1016/​j.csr.2009.01.008.

Chen, K., G.G. Gawarkiewicz, S.J. Lentz, and J.M. Bane. 2014a. Diagnosing the warming of the northeastern US coastal ocean in 2012: A linkage between the atmospheric jet stream variability and ocean response. Journal of Geophysical Research 119:218–227, https://doi.org/​10.1002/2013JC009393.

Chen, K., and R. He. 2010. Numerical investigation of the Middle Atlantic Bight shelfbreak frontal circulation using a high-resolution ocean hindcast model. Journal of Physical Oceanography 40:949–964, https://doi.org/10.1175/2009JPO4262.1.

Chen, K., R. He, B.S. Powell, G.G. Gawarkiewicz, A.M. Moore, and H.G. Arango. 2014b. Data assimilative modeling investigation of Gulf Stream Warm Core Ring interaction with continental shelf and slope circulation. Journal of Geophysical Research 119:5,968–5,991, https://doi.org/​10.1002/2014JC009898.

Chen, K., Y.-O. Kwon, and G. Gawarkiewicz. 2016. Interannual variability of winter spring temperature in the Middle Atlantic Bight: Relative contributions of atmospheric and oceanic processes. Journal of Geophysical Research 121:4,209–4,227, https://doi.org/​10.1002/2016JC011646.

Ezer, T., L.P. Atkinson, W.B. Corlett, and J.L. Blanco. 2013. Gulf Stream’s induced sea level rise and variability along the US mid-Atlantic coast. Journal of Geophysical Research 118:685–697, https://doi.org/​10.1002/jgrc.20091.

Fleming, N. 2016. Seasonal and Spatial Variability in Temperature, Salinity, and Circulation of the Middle Atlantic Bight. Ph.D. thesis, Rutgers University, 359 pp.

Forsyth, J.S.T., M. Andres, and G.G. Gawarkiewicz. 2015. Recent accelerated warming of the continental shelf off New Jersey: Observations from the CMV Oleander expendable bathythermograph line. Journal of Geophysical Research 120:2,370–2,384, https://doi.org/10.1002/2014JC010516.

Fratantoni, P., and R. Pickart. 2007. The western North Atlantic shelfbreak current system in summer. Journal of Physical Oceanography 37:2,509–2,533, https://doi.org/​10.1175/JPO3123.1.

Gawarkiewicz, G., F. Bahr, R.C. Beardsley, and K.H. Brink. 2001. Interaction of a slope eddy with the shelfbreak front in the Middle Atlantic Bight. Journal of Physical Oceanography 21:2,783–2,796, https://doi.org/10.1175/1520-0485(2001)031​<2783:IOASEW>2.0.CO;2.

Gawarkiewicz, G., K. Brink, F. Bahr, R. Beardsley, M. Caruso, J. Lynch, and C.-S. Chiu. 2004. A large-amplitude meander of the shelfbreak front in the Middle Atlantic Bight: Observations from the shelfbreak PRIMER experiment. Journal of Geophysical Research 109, C03006, https://doi.org/​10.1029/2002JC001468.

Gawarkiewicz, G., R. Todd, A. Plueddemann, and M. Andres. 2012. Direct interaction between the Gulf Stream and the shelf break south of New England. Scientific Reports 2, 553, https://doi.org/10.1038/srep00553.

Glenn, S., T. Miles, G. Seroka, Y. Xu, R. Forney, F. Yu, H. Roarty, O. Schofield, and J. Kohut. 2016. Stratified coastal ocean interactions with tropical cyclones. Nature Communications 7, https://doi.org/​10.1038/ncomms10887.

Greene, C., E. Meyer-Gutbrod, B. Monger, L. McGarry, A. Pershing, I. Belkin, P. Fratantoni, D. Mountain, R. Pickart, A. Proshutinsky, and others. 2013. Remote climate forcing of decadal-scale regime shifts in Northwest Atlantic shelf ecosystems. Limnology and Oceanography 58:803–816, https://doi.org/10.4319/lo.2013.58.3.0803.

Hare, J.A., W.E. Morrison, M.W. Nelson, M.M. Stachura, E.J. Teeters, R.B. Griffis, M.A. Alexander, J.D. Scott, L. Alade, R.J. Bell, and others. 2016. A vulnerability assessment of fish and invertebrates to climate change on the northeast US continental shelf. PloS ONE 11(2):e0146756, https://doi.org/10.1371/journal.pone.0146756.

Houghton, R.W., R. Schlitz, R.C. Beardsley, B. Butman, and J. Lockwood Chamberlin. 1982. The Middle Atlantic Bight cold pool: Evolution of the temperature structure during summer 1979. Journal of Physical Oceanography 12:1,019–1,029, https://doi.org/​10.1175/​1520-0485(1982)012​<1019:TMABCP>​2.0.CO;2.

Linder, C.A., and G. Gawarkiewicz. 1998. A climatology of the shelfbreak front in the Middle Atlantic Bight. Journal of Geophysical Research 103:18,405–18,423, https://doi.org/​10.1029/98JC01438.

Linder, C.A., G.G. Gawarkiewicz, and R.S. Pickart. 2004. Seasonal characteristics of bottom boundary layer detachment at the shelfbreak front in the Middle Atlantic Bight. Journal of Geophysical Research 109, C03049, https://doi.org/​10.1029/​2003JC002032.

Linder, C.A., G.G. Gawarkiewicz, and M. Taylor. 2006. Climatological estimation of environmental uncertainty over the Middle Atlantic Bight shelf and slope. IEEE Journal of Oceanic Engineering 31:308–324, https://doi.org/10.1109/JOE.2006.877145.

Mills, K., A. Pershing, C. Brown, Y. Chen, F.-S. Chiang, D. Holland, S. Lehuta, J. Nye, J. Sun, A. Thomas, and R. Wahle. 2013. Fisheries management in a changing climate: Lessons from the 2012 ocean heat wave in the Northwest Atlantic. Oceanography 26(2):191–195, https://doi.org/​10.5670/oceanog.2013.27.

Monim, M., 2017. Seasonal and Inter-annual Variability of Gulf Stream Warm Core Rings from 2000 to 2016. MS Thesis, University of Massachusetts Dartmouth, 113 pp.

Pershing, A., M. Alexander, C. Hernandez, L. Kerr, A. Le Bris, K. Mills, J. Nye, N. Record, H. Scannell, J. Scott, and others. 2015. Slow adaptation in the face of ocean warming leads to collapse of Gulf of Maine cod fishery. Science 350:809–812, https://doi.org/10.1126/science.aac9819.

Pickart, R. 2000. Bottom boundary layer structure and detachment in the shelfbreak jet of the Middle Atlantic Bight. Journal of Physical Oceanography 30:2,668–2,686, https://doi.org/10.1175/1520-0485(2001)031​<2668:BBLSAD>2.0.CO;2.

Pickart, R., T. McKee, D. Torres, and S. Harrington. 1999. Mean structure and interannual variability of the slope water system south of Newfoundland. Journal of Physical Oceanography 29:2,541–2,558, https://doi.org/10.1175/1520-0485(1999)029​<2541:MSAIVO>2.0.CO;2.

Smith, K.S., and R. Ferrari. 2009. Production and dissipation of compensated thermohaline variance by mesoscale stirring. Journal of Physical Oceanography 39:2,477–2,501, https://doi.org/​10.1175/2009JPO4103.1.

Smith, L.M., J.A. Barth, D.S. Kelley, A. Plueddemann, I. Rodero, G.A. Ulses, M.F. Vardaro, and R. Weller. 2018. The Ocean Observatories Initiative. Oceanography 31(1):16–35, https://doi.org/10.5670/oceanog.2018.105.

Sullivan, M.C., R.K. Cowen, and B.P. Steves. 2005. Evidence for atmosphere-ocean forcing of yellowtail flounder (Limanda ferruginea) recruitment in the Middle Atlantic Bight. Fisheries Oceanography 14(5):386–399, https://doi.org/​10.1111/j.1365-2419.2005.00343.x.

Ullman, D.S., D.L. Codiga, A. Pfeiffer-Herbert, and C.R. Kincaid. 2014. An anomalous near-​bottom cross-shelf intrusion of slope water on the southern New England continental shelf. Journal of Geophysical Research 119:1,739–1,753, https://doi.org/10.1002/2013JC009259.

Wright, W., and C. Parker, 1976. A volumetric temperature/salinity census of the Middle Atlantic Bight. Limnology and Oceanography 21:563–571, https://doi.org/10.4319/lo.1976.21.4.0563.

Zhang, W., and G. Gawarkiewicz. 2015a. Length scale of the finite amplitude meanders of shelfbreak fronts. Journal of Physical Oceanography 45:2,598–2,620, https://doi.org/​10.1175/JPO-D-14-0249.1.

Zhang, W., and G. Gawarkiewicz. 2015b. Dynamics of the direct intrusion of Gulf Stream ring water onto the Mid-Atlantic Bight shelf. Geophysical Research Letters 42:7,687–7,695, https://doi.org/​10.1002/2015GL065530.

Zhang, W.G., D.J. McGillicuddy Jr., and G.G. Gawarkiewicz. 2013. Is biological productivity enhanced at the New England shelfbreak front? Journal of Geophysical Research 118:517–535, https://doi.org/10.1002/jgrc.20068.