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Abstract Idealized models are analyzed to quantify how large‐scale river plumes interact with coastal corners with and without wind‐driven currents. The configuration has a corner formed by two perpendicular shelves (with constant slope) that are joined with a coastal radius of curvature (r_c). The buoyant plume originates from an upstream point source. Ther_cand wind forcing are varied among runs. Steep‐ and gentle‐slope runs are compared for some situations. Without winds, plumes separate from corners withr_csmaller than two inertial radii (r_i); this threshold is twice ther_c < r_itheoretical separation criterion. After separation, no‐wind plumes form an anticyclonic bulge, and reattach farther downstream. Offshore excursion increases asr_cdecreases. A downwelling‐favorable wind component along the upstream coast (τ_sx) favors separation by increasing total plume speed. An upwelling‐favorable wind component along the downstream coast (τ_sy) also increases offshore excursion. Winds blowing obliquely offshore with both these wind components advect the plume farther offshore. Wind‐driven currents that steer plumes in this situation include a downshelf jet originating on the upstream shelf and continuing around the coastal corner and beyond, offshore and upshelf surface transport downstream of the corner, and surface Ekman transport on the outer shelf. Multiple linear regressions quantify plume position sensitivity tor_c,τ_sx, andτ_sy; results are discussed in a dynamical context. Globally, many river plumes interact with coastal corners under various wind conditions. 

Abstract The Connecticut River plume is influenced by energetic ambient tides in the Long Island Sound receiving waters. The objectives of this modeling study are (a) characterizing the spatial heterogeneity of turbulent buoyancy fluxes, (b) partitioning turbulent buoyancy fluxes into bottom‐generated and interfacial shear contributions, and (c) quantifying contributions to plume‐integrated mixing within the tidal plume. The plume formed during ambient flood tides under low river discharge, spring tides, and no winds is analyzed. Turbulent buoyancy fluxes (B) and depth‐integratedBthrough the plume (Bd) are characterized by pronounced spatial heterogeneity. Strong mixing (Bd∼ 10⁻⁵‐10⁻⁴ m³/s³) occurs near the mouth, in the nearfield plume turning region, over shoals, and nearshore shallow areas. Low to moderate mixing (Bd∼ 10⁻⁸‐10⁻⁶ m³/s³) occupies half the plume. Buoyancy fluxes are first partitioned based on the depth of the shear stress minimum between plume‐generated and bottom‐generated shear maxima. Four other tested partitioning methods are based on open channel flow and stratified shear flow parameterizations. Interfacial and bottom‐generated shear contribute to different areas of intense and moderate mixing. All methods indicate a significant plume mixing role for bottom‐generated mixing, but interfacial mixing is a bigger contributor. Plume‐integrated total and interfacial mixing peak at max ambient flood and the timing of peak bottom‐generated mixing varies among partitioning methods. Two‐thirds of the mixing occurs in concentrated intense mixing areas. A parameter space with the ambient tidal Froude number and plume thickness to depth ratio as axes indicates many tidally modulated plumes are moderately to dominantly influenced by bottom‐generated tidal mixing. 

This study models Iceland’s shelf and surrounding ocean waters to quantify shelf distributions, flushing times, offshore exports (beyond the 400-m isobath), and alongshelf transports of Iceland’s riverine freshwater. Analysis of the 2019 period divides the shelf into four quadrants and follows river waters delivered to each quadrant with tracked freshwater tracers that decay over time in open-ocean waters. Tracked freshwater thicknesses are large in the southwest quadrant and near major rivers in other areas. Freshwater is present around the entire shelf, but is less prevalent in the southeast quadrant. Many river waters can reach halfway around Iceland before being exported offshore; diminishing amounts can almost entirely circumnavigate Iceland. Annual average freshwater flushing times have an approximately seasonal scale at around 3 and 4 months for eastern and western river waters, respectively. Annual average freshwater exports are larger from northern shelf quadrants than southern ones. Average alongshelf freshwater transports are downshelf. Alongshelf connectivity is strong between most quadrants and moderate between the eastern quadrants. Regressions show how export and downshelf transport increase during upwelling-favorable and downwelling-favorable winds, respectively. Results indicate the Icelandic Coastal Current has robust buoyancy signatures and connected currents in western Iceland, and has generally weaker buoyancy and less-pronounced connected flows on the eastern side. 

This dataset contains the supporting data for figures in “Icelandic Riverine Freshwater Distribution, Offshore Export, and Alongshelf Connectivity,” a manuscript for Estuarine, Coastal and Shelf Science by Michael M. Whitney (affiliated with the University of Connecticut). This study simulates Iceland’s shelf and open-ocean waters to investigate riverine freshwater distributions and transports. Tracers are applied to determine flushing times and quantify exports to the open ocean relative to downshelf transports. Results have broader relevance to Iceland’s coastal ecosystems and transports on other continental shelves. The dataset includes MATLAB data files that contain all the output data presented in the corresponding figures within the manuscript. Details about variables and units are described within the figure captions and manuscript text. Modified model code, settings, and input files are included for the Regional Ocean Model System (ROMS) application. The FORTRAN code files have the modifications for tracers that allow for decay in deep waters. The manuscript contains complete descriptions of methods, analysis, and interpretation. List of MATLAB data files: Figure01_data.mat Figure02_data.mat Figure03_data.mat Figure04_data.mat Figure05_data.mat Figure06_data.mat Figure07_data.mat Figure08_data.mat List of modified ROMS code files: def_info.F mod_scalars.F read_phypar.F step3d_t.F wrt_info.F ana_passive.h ana_psource.h List of ROMS settings and input files: iceland.h roms.in boundary2km_lonlatgrid.nc rivers2km_with_additional_rivers_lonlatgrid.nc grid_iceland2km_lonlatgrid.nc iceland2km_lonlatgrid_tideforcing_M2_NA_phase010119.nc initial2km_lonlatgrid_yearend_dyes.nc windforcing2km_lonlatgrid.nc 

This dataset is associated with a manuscript on river plumes and idealized coastal corners with first author Michael M. Whitney. The dataset includes source code, compilation files, and routines to generate input files for the Regional Ocean Modeling System (ROMS) runs used in this study. ROMS output files in NetCDF format are generated by executing the compiled ROMS code with the input files. The dataset also includes MATLAB routines and datafiles for the analysis of model results and generation of figures in the manuscript. The following zip files are included: ROMS_v783_Yan_code.zip [ROMS source code branch used in this study] coastalcorner_ROMS_compilation.zip [files to compile ROMS source code and run-specific Fortran-90 built code] coastalcorner_ROMS_input_generate_MATLAB.zip [ROMS ASCII input file and MATLAB routines to generate ROMS NetCDF input files for runs] coastalcorner_MATLAB_output_analysis.zip [MATLAB data files with selected ROMS output fields and custom analysis routines and datafiles in MATLAB formats used in this study] coastalcorner_MATLAB_figures.zip [custom MATLAB routine for manuscript figure generation and MATLAB data files with all data fields included in figures] coastalcorner_tif_figures.zip [TIF image files of each figure in manuscript]