Comments on pom98_wad.f (& comblk98_wad.h):

This version simulates wetting and drying (WAD) surrounding an island in the middle of a channel through which (stratified) tidal currents flow back and forth at a period = 1 day. This test-problem was configured from POM’s original seamount problem by Tal Ezer. The dx & dy are variable, minimum over the island is ~ 4 km, and there are 21 (=kb) unevenly-distributed sigma levels. Full 3-d POM physics with density stratification and MY’s turbulence parameterization are invoked.

Note that the dx & dy are coarse for simulation of WAD processes. In practice, one should use smaller dx and dy around 100 m (shallow waters, w/variable grid) but probably should not be much larger than 1km. To put the WAD in perspective, the mighty Indian Ocean tsunami penetrated landward only (but disastrous) about 2 km onto a resort community in Thailand – see illustration below.

The code (*.f & *.h) is sprinkled with detailed comments (on the WAD implementations), as well as edit-markers “!lyo:!wad:” and “!tne:!wad:” to facilitate transfers to existing pom98 code. Other things to watch out when modifying your existing codes are: (1) the water depth “H” (if it appears by itself) should really be “D”, and (2) the free-surface “el” etc is always negative because the reference is no longer the MSL (mean sea level) but rather over the land. There may be other things to watch out for but I can’t think of any right now...; but see “run experiences.”

l.oey

Jul/25/2007

Princeton, NJ, USA.

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Figure caption: The Indian Ocean coastline near Phuket, Thailand is a major tourist destination that was in the path of the tsunami produced by a giant offshore earthquake on December 26, 2004. This disaster resulted in a heavy loss of life. These simulated natural color ASTER (Advanced Spaceborne Thermal Emission and Reflection Radiometer) images show a 27 kilometer (17-mile) long stretch of coast 80 kilometers (50 miles) north of the Phuket airport on December 31 (middle) and also two years earlier (left). The changes along the coast are obvious (changing from green to grey) where the vegetation was stripped away by the tsunami.

The image on the right is a copy of the later ASTER scene but it includes highlighting in red for areas that have elevations within 10 meters (33 feet) of sea level. This elevation information was supplied by the Shuttle Radar Topography Mission (SRTM). The red areas appear to include most of the tsunami inundated areas.