Changes between Version 9 and Version 10 of ImplementAnalysisletkf


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Timestamp:
Jan 22, 2012, 11:01:13 AM (13 years ago)
Author:
lnerger
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  • ImplementAnalysisletkf

    v9 v10  
    2828== Overview ==
    2929
    30 For the analysis step of the LETKF algorithm, several operations related to the observations are needed. These operations are requested by PDAF by calling user-supplied routines. Intentionally, the operations are split into separate routines in order to keep the operations rather elementary as this procedure should simplify the implementation. The names of the required routines are specified in the call to the routine `PDAF_put_state_letkf` described below. With regard to the parallelization, all these routines (except `U_collect_state`) are executed by the filter processes (`filterpe=1`) only.
     30For the analysis step of the LETKF algorithm, several operations related to the observations are needed. These operations are requested by PDAF by calling user-supplied routines. Intentionally, the operations are split into separate routines in order to keep the operations rather elementary as this procedure should simplify the implementation. The names of the required routines are specified in the call to the routine `PDAF_put_state_letkf` described below. With regard to the parallelization, all these routines (except `U_collect_state`) are executed by the filter processes (`filterpe=.true.`) only.
    3131
    3232For completeness we discuss here all user-supplied routines that are specified in the interface to `PDAF_put_state_letkf`. Many of the routines are localized versions of those that are needed for the global ETKF method. Hence, if the user-supplied routines for the global ETKF method have been already implemented, one can base on these routines to speed up the implementation. Due to this, it can also be reasonable to first fully implement a global filter version and subsequently implement the corresponding localized filter by modifying and extending the global routines.
     
    5757 * [#U_init_obs_finit_obs_f_pdaf.F90 U_init_obs_f]: The name of the user-supplied routine that initializes the full vector of observations
    5858 * [#U_init_obs_linit_obs_l_pdaf.F90 U_init_obs_l]: The name of the user-supplied routine that initializes the vector of observations for a local analysis domain
    59  * [#U_prepoststepprepoststep_seik_pdaf.F90 U_prepoststep]: The name of the pre/poststep routine as in `PDAF_get_state`
     59 * [#U_prepoststepprepoststep_ens_pdaf.F90 U_prepoststep]: The name of the pre/poststep routine as in `PDAF_get_state`
    6060 * [#U_prodRinvA_lprodrinva_l_pdaf.F90 U_prodRinvA_l]: The name of the user-supplied routine that computes the product of the inverse of the observation error covariance matrix with some matrix provided to the routine by PDAF.
    6161 * [#U_init_n_domainsinit_n_domains_pdaf.F90 U_init_n_domains]: The name of the routine that provides the number of local analysis domains
     
    167167
    168168
    169 === `U_prepoststep` (prepoststep_seik_pdaf.F90) ===
    170 
    171 This routine can generally be identical to that used for the global SEIK filter, which has already been described on the [ModifyModelforEnsembleIntegration#U_prepoststepprepoststep_seik.F90 page on modifying the model code for the ensemble integration]. For completeness, the description is repeated:
     169=== `U_prepoststep` (prepoststep_ens_pdaf.F90) ===
     170
     171This routine can generally be identical to that used for the global SEIK filter, which has already been described on the [ModifyModelforEnsembleIntegration#U_prepoststepprepoststep_ens_pdaf.F90 page on modifying the model code for the ensemble integration]. For completeness, the description is repeated:
    172172
    173173The interface of the routine is identical for all filters. However, the particular operations that are performed in the routine can be specific for each filter algorithm. Here, we exemplify the interface on the example of the ETKF.
     
    412412
    413413When the ensemble integration of the forecast is completed, the analysis step is executed. Before the loop over all local analysis domains, the following routines are executed:
    414  1. [#U_prepoststepprepoststep_seik_pdaf.F90 U_prepoststep] (Call to act on the forecast ensemble, called with negative value of the time step)
     414 1. [#U_prepoststepprepoststep_ens_pdaf.F90 U_prepoststep] (Call to act on the forecast ensemble, called with negative value of the time step)
    415415 1. [#U_init_n_domainsinit_n_domains_pdaf.F90 U_init_n_domains]
    416416 1. [#U_init_dim_obs_finit_dim_obs_f_pdaf.F90 U_init_dim_obs_f]
     
    431431
    432432After the loop over all local analysis domains, it is executed:
    433  1. [#U_prepoststepprepoststep_seik_pdaf.F90 U_prepoststep] (Call to act on the analysis ensemble, called with (positive) value of the time step)
    434 
    435 
    436 
     433 1. [#U_prepoststepprepoststep_ens_pdaf.F90 U_prepoststep] (Call to act on the analysis ensemble, called with (positive) value of the time step)
     434
     435
     436