Accession Number:

ADA229821

Title:

Separation of the Mean Gulf Stream Topography from an Altimeter-Derived Reference Surface Using Genetic Algorithms

Descriptive Note:

Abstract,

Corporate Author:

NAVAL OCEANOGRAPHIC AND ATMOSPHERIC RESEARCH LAB STENNIS SPACE CENTER MS

Personal Author(s):

Report Date:

1990-01-01

Pagination or Media Count:

2.0

Abstract:

The mean dynamic topography in the reference surface used to calculate altimetric sea-surface height SSH residuals leads to significant difficulty in interpretation. When the geoid is subtracted from an individual pass the mean dynamic topography is also subtracted, leading to counterflow as strong as the Gulf Stream itself. Several synthetic geoid methods have been developed to address this problem. A simple approach involves a mathematical representation of mean and instantaneous Gulf Stream profiles. The method employs a least squares fit to SSH residuals to determine model parameters. The modeled mean Gulf Stream is then added to the SSH residual profile to allow a better depiction of the instantaneous Gulf Stream. This method works well, but convergence is often not achieved unless the initial parameter estimates are close to the correct values. Genetic algorithms GAs were used in an effort to find a more robust approach. GAs are search techniques based on the mechanics of natural selection. GAs apply the generate and test search procedure iteratively over a large set of candidate solutions. They search large numbers of candidate solutions simultaneously, and use random search andor selection rather than deterministic methods. mm

Subject Categories:

  • Physical and Dynamic Oceanography

Distribution Statement:

APPROVED FOR PUBLIC RELEASE