Research Activities > Programs > 
		Lectures>CSCAMM Students - 2006 
        >Bin Cheng 
		
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							On the Long 
							Time Regularity of the Shallow Water Equations
							 
							 
						
							
                            
                            Bin Cheng
  
							Center for Scientific Computation and Mathematical 
							Modeling at University of Maryland, College Park 
							 
							 
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							 Abstract:  
							We study the long time 
							existence of classical solutions to the Shallow 
							Water (SW) equations with pressure gradient and 
							rotational forcing that are both singular within 
							certain scaling regime of the Froude and Rossby 
							numbers. The SW dynamics is then shown to be 
							asymptotically close to the one governed by the 2-D 
							“pressureless” rotational Euler equations with 
							subcritical initial data, which in turn yields the 
							increasingly long time existence at this singular 
							regime. The novelty of our approach is the use of an 
							approximate system that is linear while still 
							capturing both the singularity and the advection 
							dynamics of the underlying nonlinear system. The 
							near periodic dynamics shown here is closely related 
							to the circular uid motions observed in geophysical 
							sciences. 
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