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|Goni, G., DeMaria, M., Knaff, J., Sampson, C., Ginis, I., Bringas, F., et al. (2009). Applications of Satellite-Derived Ocean Measurements to Tropical Cyclone Intensity Forecasting. Oceanog., 22(3), 190–197.|
|Hurlburt, H. E.: M., EJ, Richman, J. G., Chassignet, E. P., Drillet, Y., Hecht, M. W., Le Galloudec, O., et al. (2011). Dynamical Evaluation of Ocean Models Using the Gulf Stream as an Example. In B. G. Schiller A. (Ed.), Operational Oceanography in the 21st Century. Dordrecht: Springer.|
|Chassignet, E. P. (2011). Isopycnic and Hybrid Ocean Modeling in the Context of GODAE. In A. Schiller, & G. B. Brassington (Eds.), Operational Oceanography in the 21st Century (pp. 263–293).|
LaCasce, J. H., Escartin, J., Chassignet, E. P., & Xu, X. (2018). Jet instability over smooth, corrugated and realistic bathymetry. J. Phys. Oceanogr., .
Abstract: The stability of a horizontally- and vertically-sheared surface jet is examined, with a focus on the vertical structure of the resultant eddies. Over a flat bottom, the instability is mixed baroclinic/barotropic, producing strong eddies at depth which are characteristically shifted downstream relative to the surface eddies. Baroclinic instability is suppressed over a large slope for retrograde jets (with a flow anti-parallel to topographic wave propagation), and to a lesser extent for prograde jets (with flow parallel to topographic wave propagation), as seen previously. In such cases, barotropic (lateral) instability dominates if the jet is sufficiently narrow. This yields surface eddies whose size is independent of the slope but proportional to the jet width. Deep eddies still form, forced by interfacial motion associated with the surface eddies, but they are weaker than under baroclinic instability and are vertically aligned with the surface eddies. A sinusoidal ridge acts similarly, suppressing baroclinic instability and favoring lateral instability in the upper layer.
A ridge with a 1 km wavelength and an amplitude of roughly 10 m is sufficient to suppress baroclinic instability. Surveys of bottom roughness from bathymetry acquired with shipboard multibeam echosounding reveal that such heights are common, beneath the Kuroshio, the Antarctic Circumpolar Current and, to a lesser extent, the Gulf Stream. Consistent with this, vorticity and velocity cross sections from a 1/50° HYCOM simulation suggest that Gulf Stream eddies are vertically aligned, as in the linear stability calculations with strong topography. Thus lateral instability may be more common than previously thought, due to topography hindering vertical energy transfer.
Stukel, M. R., Biard, T., Krause, J. W., & Ohman, M. D. (2018). Large Phaeodaria in the twilight zone: Their role in the carbon cycle. Association for the Sciences of Limnology and Oceanography, .
Abstract: Advances in in situ imaging allow enumeration of abundant populations of large Rhizarians that compose a substantial proportion of total mesozooplankton biovolume. Using a quasi-Lagrangian sampling scheme, we quantified the abundance, vertical distributions, and sinking‐related mortality of Aulosphaeridae, an abundant family of Phaeodaria in the California Current Ecosystem. Inter‐cruise variability was high, with average concentrations at the depth of maximum abundance ranging from < 10 to > 300 cells m−3, with seasonal and interannual variability associated with temperature‐preferences and regional shoaling of the 10°C isotherm. Vertical profiles showed that these organisms were consistently most abundant at 100�150 m depth. Average turnover times with respect to sinking were 4.7�10.9 d, equating to minimum in situ population growth rates of ~ 0.1�0.2 d−1. Using simultaneous measurements of sinking organic carbon, we find that these organisms could only meet their carbon demand if their carbon : volume ratio were ~ 1 μg C mm−3. This value is substantially lower than previously used in global estimates of rhizarian biomass, but is reasonable for organisms that use large siliceous tests to inflate their cross‐sectional area without a concomitant increase in biomass. We found that Aulosphaeridae alone can intercept > 20% of sinking particles produced in the euphotic zone before these particles reach a depth of 300 m. Our results suggest that the local (and likely global) carbon biomass of Aulosphaeridae, and probably the large Rhizaria overall, needs to be revised downwards, but that these organisms nevertheless play a major role in carbon flux attenuation in the twilight zone.
|Brassington, G. B., Martin, M. J., Tolman, H. L., Akella, S., Balmeseda, M., Chambers, C. R. S., et al. (2015). Progress and challenges in short- to medium-range coupled prediction. Journal of Operational Oceanography, 8(sup2), s239–s258.|
|Stukel, M. R., Song, H., Goericke, R., & Miller, A. J. (2018). The role of subduction and gravitational sinking in particle export, carbon sequestration, and the remineralization length scale in the California Current Ecosystem. Limnology and Oceanography, 63(1), 363–383.|
|Hiester, H. R., Morey, S. L., Dukhovskoy, D. S., Chassignet, E. P., Kourafalou, V. H., & Hu, C. (2016). A topological approach for quantitative comparisons of ocean model fields to satellite ocean color data. Methods in Oceanography, 17, 232–250.|
|Manghnani, V., Morrison, J. M., Xie, L., & Subrahmanyam, B. (2002). Heat transports in the Indian Ocean estimated from TOPEX/POSEIDON altimetry and model simulations. Deep Sea Research Part II: Topical Studies in Oceanography, 49(7-8), 1459–1480.|
|Thoppil, P. G., Metzger, E. J., Hurlburt, H. E., Smedstad, O. M., & Ichikawa, H. (2016). The current system east of the Ryukyu Islands as revealed by a global ocean reanalysis. Progress in Oceanography, 141, 239–258.|