@article {gray_evidence_2024,
	title = {Evidence for Kilometer-Scale Biophysical Features at the Gulf Stream Front},
	journal = {Journal of Geophysical Research: Oceans},
	volume = {129},
	number = {3},
	year = {2024},
	note = {_eprint: https://agupubs.onlinelibrary.wiley.com/doi/pdf/10.1029/2023JC020526},
	pages = {e2023JC020526},
	abstract = {Understanding the interplay of ocean physics and biology at the submesoscale and below (<30 km) is an ongoing challenge in oceanography. While poorly constrained, these scales may be of critical importance for understanding how changing ocean dynamics will impact marine ecosystems. Fronts in the ocean, regions where two disparate water masses meet and isopycnals become tilted toward vertical, are considered hotspots for biophysical interaction, but there is limited observational evidence at the appropriate scales to assess their importance. Fronts around western boundary currents like the Gulf Stream are of particular interest as these dynamic physical regions are thought to influence both productivity and composition of primary producers; however, how exactly this plays out is not well known. Using satellite data and 2 years of in situ observations across the Gulf Stream front near Cape Hatteras, North Carolina, we investigate how submesoscale frontal dynamics could affect biological communities and generate hotspots of productivity and export. We assess the seasonality and phenology of the region, generalize the kilometer-scale structure of the front, and analyze 69 transects to assess two physical processes of potential biogeochemical importance: cold shelf filament subduction and high salinity Sargasso Sea obduction. We link these processes observationally to meanders in the Gulf Stream and discuss how cold filament subduction could be exporting carbon and how obduction of high salinity water from depth is connected with high chlorophyll-a. Finally, we report on phytoplankton community composition in each of these features and integrate these observations into our understanding of frontal submesoscale dynamics.},
	keywords = {biophysical interaction, Fronts, Gulf Stream, meanders, phytoplankton community, submesoscale},
	issn = {2169-9291},
	doi = {10.1029/2023JC020526},
	url = {https://onlinelibrary.wiley.com/doi/abs/10.1029/2023JC020526},
	author = {Gray, Patrick Clifton and Savelyev, Ivan and Cassar, Nicolas and L{\'e}vy, Marina and Boss, Emmanuel and Lehahn, Yoav and Bourdin, Guillaume and Thompson, Kate A. and Windle, Anna and Gronniger, Jessica and Floge, Sheri and Hunt, Dana E. and Silsbe, Greg and Johnson, Zackary I. and Johnston, David W.}
}
@article {hirzel_high_2023,
	title = {High resolution analysis of plankton distributions at the middle atlantic bight shelf-break front},
	journal = {Continental Shelf Research},
	volume = {267},
	year = {2023},
	pages = {105113},
	abstract = {The Middle Atlantic Bight (MAB) is a highly productive ecosystem, supporting several economically important commercial fisheries. Chlorophyll enhancement at the MAB shelf-break front has been observed only intermittently, despite several studies suggesting persistent upwelling at the front. High resolution cross-frontal transects were conducted during three two-week cruises in April 2018, May 2019, and July 2019. Mesoplankton distributions at the front were measured with a Video Plankton Recorder equipped with hydrographic and bio-optical sensors. Zooplankton were also sampled with a Multiple Opening/Closing Net and Environment Sensing System. Each of the three cruises had distinctly different frontal characteristics, with lower variability in frontal position in April 2018 and higher variability in May and July 2019, primarily due to frontal eddies and a Gulf Stream warm core ring, respectively. Eulerian means of all transect crossings within each cruise did not show mean frontal chlorophyll enhancement in April 2018 or July 2019, despite individual crossings showing chlorophyll enhancement in April 2018. Transformation of the April 2018 data into a cross-frontal coordinate system revealed a weak enhancement of chlorophyll and copepods at the front. Mean frontal chlorophyll enhancement was observed in May and was associated with enhancement in the periphery of a frontal eddy rather than the front itself. None of the planktonic categories observed were enhanced at the front in the cross-shelf mean distribution, though diatom chains and copepods were more abundant inshore of the front, particularly in May and July 2019, as well as within the center of a frontal eddy in May. The high variability of the MAB frontal region obscured the impact of ephemeral frontal enhancement in mean observations of April 2018, while frontal eddies contributed to chlorophyll enhancement in mean observations of May 2019. The influence of both argues for the necessity for 3-D models rather than idealized 2-D models to explain frontal behavior and its effects on biological responses.},
	keywords = {Chlorophyll, Eddies, Fronts, Plankton, Shelf-break, Video plankton recorder},
	issn = {0278-4343},
	doi = {10.1016/j.csr.2023.105113},
	url = {https://www.sciencedirect.com/science/article/pii/S0278434323001905},
	author = {Hirzel, Andrew J. and Alatalo, Philip and Oliver, Hilde and Petitpas, Christian M. and Turner, Jefferson T. and Zhang, Weifeng (Gordon) and McGillicuddy, Dennis J.}
}
@article {RN20,
	title = {Horizontal Scales of Variability over the Middle Atlantic Bight Shelf Break and Continental Rise from Finescale Observations},
	journal = {Journal of Physical Oceanography},
	volume = {43},
	number = {1},
	year = {2013},
	pages = {222-230},
	type = {Journal Article},
	abstract = {Observations with fine horizontal resolution are used to identify the horizontal scales of variability over the Middle Atlantic Bight (MAB) shelf break and continental rise. Spray gliders collected observations along two alongshelf transects over the continental rise in March{\textendash}April 2006 and along 16 cross-shelf transects over the shelf break and continental rise during July{\textendash}October 2007. Horizontal resolution varied from 1 km or finer over the shelf to 6 km in deep water. These observations allow horizontal thermohaline variability offshore of the MAB shelf break to be examined for the first time. Structure functions of temperature and salinity, the mean square difference between observations separated by specified distances, reveal the horizontal spatial scales in the region. Exponential (e-folding) scales of temperature and salinity increase from 8{\textendash}13 km near the shelf break to about 30 km over the continental rise. Just offshore of the shelf break, alongshelf structure functions exhibit periodicity with a 40{\textendash}50-km wavelength that matches the wavelength of shelfbreak frontal meanders. Farther offshore, alongshelf structure functions suggest a dominant wavelength of 175{\textendash}250 km, but these scales are only marginally resolved by the available observations. Examination of structure functions of along-isopycnal salinity (i.e., spice) suggests that interleaving of shelf and slope water masses contributes most of the horizontal variability near the MAB shelf break, but heaving of isopycnals is the primary source of horizontal variability over the continental rise.},
	keywords = {Continental shelf/slope, Fronts, In situ oceanic observations, North Atlantic Ocean, oceanic, Profilers},
	issn = {0022-3670 1520-0485},
	doi = {10.1175/jpo-d-12-099.1},
	url = {https://doi.org/10.1175/JPO-D-12-099.1},
	author = {Todd, Robert E. and Gawarkiewicz, Glen G. and Owens, W. Brechner}
}
