| Hurricane waves, swell prediction and storm surf forecasting |
| Monday, 20 August 2012 10:31 |
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Hurricane waves cause damages in the coastal regions. Can the usual swell forecast apply to storm surges? Is it safe to go surfing during the hurricane season?The first hurricane wave models developed in the 1950 were based on significant wave height and period. Later, during the 1990's, computers enabled better ocean wind and wave prediction models, with new and advanced calculations. Recently, Chung-Sheng Wu, Arthur Taylor, Jye Chen and Wilson Shaffer wrote a paper about the complexity of high winds near the eye center of hurricanes, where measurements have a high degree of uncertainty. The National Weather Service/NOAA scientists confirmed that in the six major hurricanes of the U.S. East Coast and the Gulf of Mexico, the parametric model gives wave height predictions within 5% error compared with the measured buoy wave data. Because field observations over the ocean are extremely sparse during a hurricane, NOAA researchers installed a radar on the aircraft P3 to measure the wave spectrum field during hurricane motion. They developed an empirical method of predicting dominate swell wave direction. This information can be used with a coastal wave model for modeling coastal flooding. It is concluded that the inland flooding is the combined result of a high storm surge elevating the water level on a mild beach slope, causing wave breaking process further inland and swash a high wave run-up on the beach. Without storm surges elevation, the wave set-up is limited and wave run-up is mostly confined on the foreshore slope. Finally, the paper concludes that the solution of hurricane wave forecasting is still wanted, thus observations of waves at the coasts are required for monitoring and model verification. So, if you've decided to hit the waves during the hurricane season, make sure to check the conditions on your local spot and your national weather service. Learn how waves are formed, here. |
