Development of SURGE II Program with Application to the Sabine-Calcasieu Area for Hurricane Carla and Design Hurricanes.

摘要

SURGE II is a program for calculation of storm surges and tides in a bay or estuary of the type where frictional resistance dominates over Coriolis force. It includes the provision for subgrid scale barriers and channels as well as allowing for overtopping of barriers and flooding of and recession from normally dry regions adjoining the bay or estuary. The theory and numerical algorithm is discussed in detail. A user's guide for the program is also provided. Application of the program, in respect to astronomical tides and hurricane surges, is made for the Sabine-Calcasieu region which straddles the Texas and Louisiana boundary. For normal tide conditions, cities such as Beaumont, Orange, and Lake Charles are connected to the sea via rivers, which in the numerical model must be represented as subgrid scale channels as long as the basic grid scale is of the order of a nautical mile. Under hurricane surge conditions, however, the overland flooding can greatly expand their connection to the sea. Calibration of channel friction is carried out via the astronomical tide simulation. Calibration of the block friction is carried out using data on a previous storm of record, Hurricane Carla. An example application is provided for standard project hurricanes (SPH). The response for a large radius SPH of slow speed and one of moderate speed of translation is examined. Also, the effect of rainfall is examined by running the latter storm with and without rainfall.