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The images presented here show a comparison of two observational
analyses of the Gulf Stream, one from the Naval Oceanographic Office
(NAVOCEANO) and the second from the Naval Eastern Ocean Center
(NAVEASTOCEANCEN) with the Gulf Stream location as determined directly from
the Global RTOFS model, overlaid on maps of the Global RTOFS Sea Surface
Temperature, Sea Surface Height, Surface Currents, and the
high resolution Real-Time Global Sea Surface Temperature
analysis (RTG) product.
The Global RTOFS Gulf stream location is defined as the intersection
of the 12°C isotherm and the 400m isobath (Halkin and Rossby, 1985).
The Hausdorff distance between two sets of points (in this case the
Gulf Stream North Wall Navy analyses and the North Wall from the
Global RTOFS model) is
the greatest of all the distances from the points in one set to the
closest point in the other set.
The Modified Hausdorff distance is the minimum of the Hausdorff
distances computed by swapping the point sets.
More information on the Hausdorff distance metric is available here.
Click on images to enlarge
Halkin, D. and T. Rossby (1985): The Structure and Transport of the Gulf
Stream at 73°W. Journal of Physical Oceanography, 15,
Hausdorff, F. (1914): Grundzüge der Mengenlehre, Leipzig: Veit,
ISBN 978-0-8284-0061-9 Reprinted by Chelsea in 1949.
M. P. Dubuisson and A. K. Jain (1994): A Modified Hausdorff distance for
object matching. ICPR94, A, 566-568