





1.0 



- Port Lavaca 





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 E 



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o 

 CO 



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" ■ 244 246 248 250 252 254 256 258 260 262 264 266 268 270 272 



Year Day 1997 



Figure 25. Time series of water-surface elevation measured at Port Lavaca station 



Beginning on YD 262 and extending through 266, wind speed increased from daily 

 peak speeds of 6 m/sec for the first 3-week period to a maximum speed of 17 m/sec on 

 YD 265. Minimum daily wind speed of 5 m/sec on YD 264 and 265 are about the same 

 as the peak speed for the initial 3-week period. Wind direction for the period YD 262 

 through 266 shifted from the east to the south. The strong wind together with its 

 southerly direction induced water level at both the Galveston and Port Lavaca stations to 

 increase to 0.74 and 0.70 m, respectively, which are the highest maximum water-surface 

 elevations recorded during the 1-month modeling period. 



The wind remained strong through YD 267, then slowly began to diminish. Wind 

 direction, however, shifted from the south to the north, resulting in a pronounced drop in 

 the water level at both the Galveston and Port Lavaca stations. The minimum water level 

 at the Port Lavaca station was about 0.10 m. Consequently, over the 4-day period of 

 YD 265 through 269, wind speed and its corresponding direction resulted in a maximum 

 water-level range of 0.8 m, or approximately three times the typical tidal range in the bay. 



Discussion of calibration resuits 



For this DMS appUcation, the model adequately reproduces both the phase and 

 magnitude of the water velocity measured by the current meter in the GIWW, which is 

 sta 1 (Figure 26). Typically, calculated velocity was within 5 cm/sec of the 

 measurements. Notable discrepancies occur from YD 265 through 267, during a strong 

 wind, for which calculated velocity exceeded the measured by as much as 1 1 cm/sec, or 

 40 cm/sec for the model versus 29 cm/sec for the current meter. 



30 



Chapter 3 Circulation Modeling 



