Mathematics Colloquium: AMS: Frequency Downshift in the Ocean

2019-04-24

4:10pm CUE 114

John Carter

A wave train is a group of waves of similar wavelengths traveling in the same direction. A wave train is said to “downshift” if its frequency decreases as it evolves. We begin by analyzing data from a series of tightly controlled laboratory experiments. Some of these experiments exhibit downshift while others do not. Our goal is to determine and understand the physical mechanism behind downshift. We use generalizations of the nonlinear Schrödinger equation, a nonlinear partial differential equation (PDE), to study the experimental data. We will discuss the pros and cons of these model equations. We conclude by using the PDEs to study a classical series of ocean data in which some wave trains downshifted while others did not.