Automated system and method for vertical gradient correction

Patent metadata

Field	Value
Publication number	US-9792564-B2
Application number	US-201113325398-A
Country	US
Kind code	B2
Filing date	Dec 14, 2011
Priority date	Dec 14, 2011
Publication date	Oct 17, 2017
Grant date	Oct 17, 2017

Abstract

System and method for maintaining the observed vertical structure of ocean temperature and salinity in data assimilation systems that otherwise would produce overly smoothed ocean vertical structure. The present embodiment uses a multi-layer least squares minimization technique in which the ocean is split into layers with fundamentally different vertical gradients, and the dynamic ocean layers are constrained by the observed vertical gradients of the layer itself.

First claim

What is claimed is:

1. A computer-implemented method for constructing synthetic sound speed profiles comprising the steps of:
identifying ocean observational data that includes temperature and salinity measurements for an ocean location;
generating, based on the ocean observation data, a plurality of layers throughout the depth of the ocean at the ocean location, wherein the plurality of layers includes a surface layer, a mixed layer, a dynamic layer, and a deep ocean layer;
identifying an interface between each of the plurality of layers, each of the interfaces occurring at an interface ocean depth;
applying a dynamic layer cost function to the dynamic layer to compute vertical gradient constraints based on a vertical gradient of the ocean observational data and other constraints in each of the plurality of layers, wherein the vertical gradient constraints are incorporated into the synthetic sound speed profiles;
applying the vertical gradient constraints in each of the plurality of layers to constrain corresponding layer profiles of each of the plurality of layers, wherein the vertical gradient constraints include:
first guess temperature and salinity fields for constraining the surface layer,
observed temperature at the mixed layer depth for constraining the mixed layer, and
observed subsurface temperature and salinity for constraining the deep ocean layer;

combining the constrained layer profiles of each of the plurality of layers to construct the synthetic sound speed profiles, wherein each of the synthetic sound speed profiles is aligned to a corresponding observed profile within less than 8 meters per second;
using the synthetic sound speed profiles to generate a three-dimensional synthetic model of temperature and salinity at the ocean location, wherein each of the plurality of layers represented in the three-dimensional synthetic model is constrained by at least one of the vertical gradient constraints; and
generating an ocean forecast that accounts for the vertical gradient based on the three-dimensional synthetic model.

2. The method as in claim 1 wherein
the surface layer has a surface layer temperature profile and a surface layer salinity profile;
the dynamic layer has a dynamic layer temperature profile and a dynamic layer salinity profile; and
the deep ocean layer has a deep ocean temperature profile and deep ocean salinity profile.

3. The method as in claim 1 wherein the step of generating the plurality of layers comprises the step of:
computing each of the interface ocean depths based on the ocean observational data.

4. The method as in claim 1 wherein the vertical gradient constraints constrain the vertical gradient to at least one gradient selected from a group consisting of background gradients, first guess gradients, empirical orthogonal function (EOF) mode temperature vertical gradients, and EOF-mode salinity vertical gradients.

5. The method as in claim 4 further comprising the steps of:
computing a first layer profile for one of the plurality of layers based on the dynamic layer cost function and the vertical gradient constraints;
computing at least one other profile for another of the plurality of layers based on the first layer profile and the vertical gradient constraints; and
selecting the vertical gradient constraints from a group consisting of climatological temperature and salinity fields, vertical gradient of the climatological temperature and salinity fields, the first guess temperature and salinity fields, vertical gradient of the first guess temperature and salinity fields, plurality of EOF-mode representation of the temperature and salinity fields, vertical gradient of the plurality of EOF-mode representation of the temperature and salinity fields, the observed temperature at the mixed layer depth, observed sea surface height anomaly, the observed subsurface temperature, and observed subsurface salinity.

6. The method as in claim 5 wherein the dynamic layer cost function comprises:

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Assignees

• Helber Robert W
• Barron Charlie N
• Carnes Michael R
• Us Navy

Inventors

• Helber Robert W
• Barron Charlie N
• Carnes Michael R

Classifications

• G06Q10/00 Primary

  Administration; Management · CPC title