Data Assimilation Techniques for Application to the RAMS and WRF Models. Task Order Report

Abstract

Data assimilation, which can be loosely defined as the techniques to best utilize observational data in conjunction with a numerical simulation, has continued to be a challenging problem for the atmospheric numerical modeling field. Past techniques of objective analysis (Cressman, Barnes, etc.) were simple attempts to interpolate randomly-located observations of basic state variables to a regular grid structure. Within the past decade, schemes based on variational numerical methods have become popular. Variational schemes use the concept of the minimization of a cost function. A simple example of a cost function could be the domain average of the squared differences between an analyzed field and the observations. By adjusting the analyzed field, the size of the cost function is affected. The resultant solution is the analyzed field when the cost function is at a minimum.

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Document Details

Document Type
Technical Report
Publication Date
Aug 01, 2005
Accession Number
ADA440350

Entities

People

  • Craig J. Tremback
  • John S. Snook
  • Robert L. Walko

Tags

Communities of Interest

  • Energy and Power Technologies
  • Ground and Sea Platforms

DTIC Thesaurus Topics

  • Assimilation
  • Case Studies
  • Computers
  • Data Analysis
  • Geography
  • Kalman Filters
  • Mathematical Filters
  • Measurement
  • Meteorological Phenomena
  • Meteorology
  • Software Design
  • Statistical Analysis
  • Surface Temperature
  • Test And Evaluation
  • Three Dimensional
  • Urban Areas
  • Weather Forecasting

Readers

  • Approximation Theory.
  • Ocean-Atmosphere Mesoscale Modeling, Data Assimilation, and Flux Boundary Layers
  • Systems Analysis and Design