j.m. lilly

oceanographer

Estimation of eddy vorticity from individual particle trajectories. A simulation of a nonlinear eddy at 24°N at 512×256 resolution is tracked by 512×256=131,072 particles, courtesy of {Jeffrey Early}. The coherent vortex extraction method of {Lilly, Scott, and Olhede (2011)} allows spatially-averaged vorticity, within ellipses that are inferred from eddy-trapped trajectories, to be estimated with remarkable precision. Color is vorticity. Check out the {talk}.