LCS Maps for 28 Mar 1200Z to 1 Apr 1200Z 2019, Issued 27 Mar 2019

The following figures show the 3D Finite-Time Lyapunov Exponents (FTLEs) on the surface in the domain, at different times. These FTLEs are for a time window of 6 or 96 hours for the forecast of 28 March 2019 to 1 April 2019.

The figures below show the 3D FTLEs in the domain, at different times. These FTLE computations are for a time window of 6 or 96 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 FTLE field specifies the amount of stretching of the flowmap in the considered time interval. Specifically, the forward / backward 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 = 13:00 CET, i.e., CET is 1 hour ahead of Zulu time.


Calypso Domain (1/200 deg resolution)

96-hr Forecast FTLE at 4 meters depth on April 1 1200Z

Date 12:00Z
April 1
(Forward)
FTLE_forward_000200cm_96hr_20190328_1200.png
April 1
(Backward)
FTLE_backward_000200cm_96hr_20190328_1200.png

6-hr Forecast Forward FTLE at 4 meters depth on four time instances for March 28 1200Z - March 30 0600Z

Start Date 12:00Z 18:00Z 00:00Z 06:00Z
March 28 FTLE_forward_000200cm_06hr_20190328_1200.png
FTLE_forward_000200cm_06hr_20190328_1800.png
FTLE_forward_000200cm_06hr_20190329_0000.png
FTLE_forward_000200cm_06hr_20190329_0600.png
March 29 FTLE_forward_000200cm_06hr_20190329_1200.png
FTLE_forward_000200cm_06hr_20190329_1800.png
FTLE_forward_000200cm_06hr_20190330_0000.png
FTLE_forward_000200cm_06hr_20190330_0600.png

6-hr Forecast Backward FTLE at 4 meters depth on four time instances for March 28 1200Z - March 30 0600Z

Start Date 12:00Z 18:00Z 00:00Z 06:00Z
March 28 FTLE_backward_000200cm_06hr_20190328_1200.png
FTLE_backward_000200cm_06hr_20190328_1800.png
FTLE_backward_000200cm_06hr_20190329_0000.png
FTLE_backward_000200cm_06hr_20190329_0600.png
March 29 FTLE_backward_000200cm_06hr_20190329_1200.png
FTLE_backward_000200cm_06hr_20190329_1800.png
FTLE_backward_000200cm_06hr_20190330_0000.png
FTLE_backward_000200cm_06hr_20190330_0600.png