HR: 0800h
AN: OS41D-0499    [Abstracts]
TI: Are There Poincare Waves in The Chesapeake Bay?
AU: * Maa, J P
EM: maa@vims.edu
AF: Virginia Institute of Marine Science, College of William and Mary, Rt. 1208, Greate Road, Gloucester Point, VA 23062 United States
AU: Kwon, J I
EM: jikwon@vims.edu
AF: Virginia Institute of Marine Science, College of William and Mary, Rt. 1208, Greate Road, Gloucester Point, VA 23062 United States
AU: Shen, J
EM: shen@vims.edu
AF: Virginia Institute of Marine Science, College of William and Mary, Rt. 1208, Greate Road, Gloucester Point, VA 23062 United States
AU: Kim, S
EM: Sung-Chan.Kim@erdc.usace.army.mil
AF: Environmental Lab., ERDC, Corps of Engineers, US Army, 3909 Halls Ferry Rd, Vicksburg, MS 39180 United States
AB: Kelvin and Poincare waves are both linear waves caused by the Coriolis force when waves travel in a large straight channel. Although they both propagate along the channel, their characteristics are different. For Kevin waves, although the wave amplitude decreases across the channel, there is no lateral current. For Poincare waves, the amplitudes oscillate across the channel, and there are lateral currents. These lateral currents provide a great potential for lateral mixing, if existed. Using two numerical three-dimensional (3-D) hydrodynamic models (EFDC and UnTRIM), a study was carried out to check the characteristics and the existence of Poincare waves in the Chesapeake Bay. Because the numerical models include nonlinear terms, the development of nonlinear waves is evident. The model results demonstrated that the features of Kelvin waves and Poincare waves are both presented in the modification of the input waves as well as in the high order nonlinear waves. In other words, the frequencies of Poincare waves derived from the classical linear wave system changed because of the non-linear effects. The model results also confirmed the existence of Poincare waves in the Chesapeake Bay which is highly irregular in geometry and bathymetry. Although the amplitudes for Poincare waves are small, on the order of centimeters, they still provide a strong lateral mixing mechanism, because of their long wave periods, at the center of channel.
DE: 9800 GENERAL OR MISCELLANEOUS
SC: Ocean Sciences [OS]
MN: 2004 AGU Fall Meeting