The salinity data from mid-water and bottom

depth at station M5 and the surface salinity at station M3 were low-passed using the 34-h Lanczos filter to obtain the sub-tidal record. As for other datasets, the Chesapeake Bay National Estuarine Research Reserve (CBNERR) measured surface salinity at two stations, Taskinas Creek and Clay Bank in the York River (YR), VA. During Hurricane Isabel, salinity was measured by YSI-6600 Sondes operated by CBNERR at fixed stations at Sweet Hall, Taskinas Creek, Clay Bank, and Goodwin Islands in the YR. Meteorological data were collected from a total of 13 stations around CB operated selleck chemical by NOAA and the National Data Buoy Center (NDBC). Typically, wind data were taken at a height of 10 m above mean sea level (MSL) and atmospheric pressures were observed at MSL. River stream flow data from CB tributaries were obtained from the US Geological Survey (USGS) for both hurricanes (Table 3). The baroclinic circulation in CB was

performed using the semi-implicit Eulerian–Lagrangian Finite Element (SELFE) model, a free surface hydrostatic, three-dimensional VX-809 supplier cross-scale circulation model on unstructured grids (Zhang and Baptista, 2008, Liu et al., 2008a, Liu et al., 2008b and Burla et al., 2010). SELFE uses a semi-implicit Galerkin finite-element method for the pressure gradient and the vertical viscosity terms, which are treated implicitly, and for other terms treated explicitly. To solve the vertical velocity, a finite-volume method is applied to a typical prism, because it serves as a diagnostic variable for local volume conservation when a steep slope is present (Zhang et al., 2004). SELFE treats the advection in

the transport equations with the total variation diminishing (TVD) scheme. A higher-order finite-volume TVD scheme is a preferable option in SELFE. TVD is the technique of obtaining high-resolution, second-order, oscillation-free, explicit scalar difference Vildagliptin schemes by the addition of a limited anti-diffusive flux to a first-order scheme (Sweby, 1984). Osher (1984) defined the flux differences for a general three-point E-scheme, which is a class of semi-discrete schemes approximating the scalar conservation law. These flux differences are used to define a series of local Courant–Friedrichs–Levy (CFL) numbers. Superbee (Roe, 1986) is used as a flux limiting function. SELFE adapts the Generic Length Scale (GLS) turbulence closure through the General Ocean Turbulence Model (GOTM) suggested by Umlauf and Burchard, 2003 and Umlauf and Burchard, 2005, taking advantages from a number of level 2.5 closure schemes such as k–ε ( Rodi, 1984), k–ω ( Wilcox, 1998); Mellor and Yamada scheme ( Mellor and Yamada, 1982). In this study, the k–ε scheme is used. The horizontal grid used is shown in Fig. 3. This grid has 20,784 elements, 11,582 nodes, and 32,386 sides on the surface. At least three horizontal grid cells resolve the channel of the main Bay.