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Ticket Diff – NEMO

Changes between Version 1 and Version 5 of Ticket #2175


Ignore:
Timestamp:
2019-08-23T18:33:16+02:00 (5 years ago)
Author:
smueller
Comment:

Legend:

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Added
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  • Ticket #2175

    • Property Keywords harmonic_analysis added; harmonic analysis removed
    • Property Priority changed from low to high
    • Property Status changed from new to assigned
  • Ticket #2175 – Description

    v1 v5  
    33||=Action       || ''ENHANCE-05_SimonM-Harmonic_Analysis''                                 || 
    44||=PI(S)        || ''Simon Müller, Nicolas Bruneau''                              || 
    5 ||=Digest       || ''This action will enhance the harmonic analysis diagnostics available in the current code: this includes a revamp of the implementation and the namelist, the addition of three-dimensional diagnostics, the addition of restartability, and an improvement of the computational efficiency.''      || 
     5||=Digest       || ''This action will enhance the tidal harmonic-analysis diagnostics available in the NEMO framework: the replacement of the current implementation by a facility for generic multiple linear regression will enable tidal harmonic analyses of three-dimensional fields, make harmonic analyses across model restarts possible, and improve the computational efficiency of the analysis, as well as facilitate a wide range of non-tidal regression analyses.''      || 
    66||=Dependencies ||                                                            || 
    77||=Branch       || ''[source:/NEMO/branches/$YEAR/dev_r{REV}_{ACTION_NAME}]'' || 
     
    1313==== Abstract 
    1414 
    15 This action will enhance the harmonic analysis diagnostics available in the current code: this includes a revamp of the implementation and the namelist, the addition of three-dimensional diagnostics, the addition of restartability, and an improvement of the computational efficiency. 
     15This action will enhance the tidal harmonic-analysis diagnostics available in the NEMO framework: the replacement of the current implementation by a facility for generic multiple linear regression will enable tidal harmonic analyses of three-dimensional fields, make harmonic analyses across model restarts possible, and improve the computational efficiency of the analysis, as well as facilitate a wide range of non-tidal regression analyses. 
    1616 
    1717===== Description 
    1818 
    19 The harmonic analysis diagnostics available in the current code are limited to two-dimensional fields (surface only), are activated via a preprocessor key, use unconventional namelist parameter names, and use a mixture of dynamic and static allocation for large arrays. This action will update the existing option with dynamic allocation of large arrays throughout, with logical control (removing the preprocessor key), with renamed namelist parameters (in line with the naming convention), with optional three-dimensional diagnostics, and with restartability of the harmonic analysis; it also aims to enhance the efficiency of the diagnostic algorithm. This work will build on and benefit from aspects of a tested implementation of both three-dimensional harmonic analysis and an algorithm of higher computational efficiency by Nicolas Bruneau into a pre-4.0beta version of NEMO. 
     19The harmonic-analysis diagnostics available in the current reference code is limited to two-dimensional fields (surface only), is activated via a preprocessor key, uses unconventional namelist parameter names, uses a mixture of dynamic and static allocation for large arrays, and appears to be computationally inefficient. Further, while being based on multiple linear regression, the current implementation does not provide for regressions on harmonic components other than tidal constituents. 
     20 
     21This action will replace the current tidal harmonic-analysis diagnostics with a generic implementation for multiple linear regression analysis that can be utilised for both tidal harmonic and non-tidal regression analyses. This implementation will provide harmonic-analysis diagnostics enhancements previously tested in a pre-4.0beta NEMO version by N. Bruneau: the analysis of three-dimensional fields, analysis across model restarts, and improved computational efficiency. 
     22 
     23In contrast to both the existing harmonic analysis diagnostics in the reference NEMO code and the enhanced pre-4.0beta version by N. Bruneau, the new implementation will make extensive use of XIOS and an off-line tool. This approach should make it possible to simplify the regression analysis-related Fortran module in the core NEMO code, to relocate the regression-analysis configuration to XIOS configuration files, and to enable the selection of any model field handled by XIOS for analysis. 
    2024 
    2125===== Implementation