The Quasigeostrophic (QG) equations are an important reduced model for rotationally-constrained flow in our atmosphere and oceans. In the QG regime, turbulent flow is dominated by coherent vortices or eddies. These vortices are observed in the ocean, the atmospheres of giant planets and possibly in astrophysical disks. In two-dimensional flow the only important interaction is the merger of two vortices of the same sign. In three-dimensional flow vortices may either merge or align vertically. The vertical alignment of coherent vortices is apparent in numerical simulations where it leads to the formation of large vertical scale features. In this thesis I studies two cases of vortex merger and alignment, a reduced moment model and a full 3D numerical simulation.
Committee members: Keith Julien (APPM), Jeff Weiss (ATOC), Bengt Fornberg, James Meiss (APPM), Ralph Milliff (CORA)

