The following figures show the 3D Finite-Time Lyapunov Exponents (FTLEs) at the bottom level of the domain. These FTLEs are for a time window of 72 for the forecast of 20 April 2021 to 23 April 2021.
The figures below show the 3D FTLEs in the domain. These FTLE computations are for a time window of 72 hours for the forecasts on the dates as specified. The flowmaps were calculated using a PDE-based approach with 5th order spatial and 3rd order temporal schemes, and a novel composition based approach.
The 3D FTLE field specifies the amount of stretching of the flowmap in the considered time interval. Specifically, the forward / backward 3D FTLE is a logarithmic scaling of the dominant singular values of the forward / backward flowmap with the time duration of interest. The forward FTLE ridges thus highlight codimension-one manifolds (curves in 2D, surfaces in 3D) that repel particles starting on either side, whereas the backward FTLE ridges highlight codimension-one manifolds that attract particles towards the ridge that originally start far apart.
As a reminder, 12:00Z = 05:00 PDT, i.e., PDT is 7 hours behind Zulu time.
| Release Time | Forward FTLE | Backward FTLE |
|---|---|---|
| 0900 PDT (1600Z) |
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| 1500 PDT (2200Z) |
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