Tricoche, X.Scheuermann, G.Hagen, H.2015-02-162015-02-1620011467-8659https://doi.org/10.1111/1467-8659.00539Topological methods produce simple and meaningful depictions of symmetric, second order two-dimensional tensor fields. Extending previous work dealing with vector fields, we propose here a scheme for the visualization of time-dependent tensor fields. Basic notions of unsteady tensor topology are discussed. Topological changes - known as bifurcations - are precisely detected and identified by our method which permits an accurate tracking of degenerate points and related structures.10.1111/1467-8659.00539461-470