Research

Fluid trajectories in the eddy show a mix of chaotic (red) regions and non-chaotic (blue and green) surfaces.

Applications of Chaos Theory in the Ocean

Mixing is an important consideration in the understanding of how properties such as heat and oxygen are transferred down from the ocean surface, or how nutrients are brought up from depth. Harmful algal blooms can be locked to such processes. In work with colleagues Irina Rypina and Tamay Ozgokmen, I use chaos theory to try to understand these processes as they might act in an ocean eddy.

Locations of Major sills in North Atlantic Ocean

Deep Circulation, Overflows, and Canyon Flows

The ocean is naturally divided into deep basins and there are currents of dense water that flow around and between them.

When eel larvae are released in the Sargasso Sea (dashed box) and allowed to drift for one year, with ability to change depths diurnally but not swim horizontally, very few are able to reach the east coast continental shelf, as shown by the probability map. This suggests that horizontal swimming is important.

Biophysical Modeling

Most fish and benthic-associated invertebrates use a reproductive strategy involving the spawning of hundreds to millions of eggs that hatch into small and vulnerable planktonic larvae.

Figure 1. Primary EARSAP topographic influences in relation to the Tokar Gap as seen in the NASA SRTM map of Africa. Labeled features include the Ethiopian Highlands, the East African Highlands, the Great Rift Valley/Turkana Valley region. The large-scale and high resolution domains are also indicated (black rectangles), as are the principle lower wind patterns of the summertime lower tropospheric circulation across the region (blue arrows) and orographic jets (red arrows). Stations providing atmospheric data for model verification are indicated by black dots and points used to evaluate model profiles and vertical cross sections in the analysis are indicated by red dots/lines.

Atmospheric and Climate Research

Northwest Africa and Arabia are home to a variety of fascinating atmospheric phenomena that have strong climatic and socio-economic consequences. These include the summer Monsoon, mesoscale convective complexes, wind jets and dust storms.