1%), it is assumed that the salinity has reached the equilibrium state. The modeled salinity reached the equilibrium state approximately 150 days after the cold start. We first examined the time series of longitudinal velocities (surface and bottom) under local wind forcing, as shown in Fig. 16. The time series were plotted for five stations: CB3.3C, in the upper Bay, CB4.4 and CB5.3 in the middle Bay, and CB6.3 and CB7.4 in the lower Bay. The results for Hurricane Floyd are shown on the left while those for Isabel are on the right, Fluorouracil chemical structure and the dashed lines denote the four-day window when local hurricane winds were imposed on the estuary. Several features can be noted immediately. First, despite the existence of spatial

variability, it appears that a consistent Bay-wide sub-tidal velocity pattern emerges if one takes an ensemble across all five stations. Fig. 17 is a schematic drawing of the distinct two-pulse pattern that is revealed. For Hurricane Floyd, it shows that the surface current initially flows seaward followed by a landward flow, whereas for AZD5363 purchase Hurricane Isabel, the surface current initially flows landward followed by a seaward flow. This two-pulse feature is closely associated with the sea level adjustment of the estuary to the local wind forcing; for Hurricane Floyd, the onset of down-estuary wind generates a down-estuary net volume

transport and, at the end of the event, the sea level relaxes; for Hurricane Isabel, the onset of wind is up-estuary, and volume transport is up-estuary. This

is consistent with the findings of CS, in that the two-pulse feature is a basic pattern of an estuary responding to the steady local wind forcing involving an exchange flow. Given that the present study is conducted using the actual Bay geometry and under strongly unsteady wind conditions during a hurricane, there are, however, significant differences between our results and those of CS. For example, the large sub-tidal velocity pulses, at the Bay mouth for Hurricane Floyd and in the upper Bay for Hurricane Isabel, deviate substantially from a symmetric two-pulse pattern. Furthermore, Bortezomib clinical trial if one connects the largest sub-tidal velocity in each time series from the lower Bay to the upper Bay, as shown by the green line in Fig. 16, a clear disturbance can be seen in the propagation pattern along the time versus space domain. This suggests that the forced long wave induced by the propagation of a storm plays an important role in shaping the transient response of the Bay to the hurricane forcing. Fig. 18 shows the salinity response to the local wind. The response during Hurricane Floyd (left) is different from that during Hurricane Isabel (right), as the sub-tidal salinity has a major drop during Floyd, whereas it increased during Isabel. These large variations of sub-tidal salinity are associated with the disturbances propagating down and up the Bay, and are similar to those which were observed in the sub-tidal velocity time series.