| 261 | | |
| 262 | | We cover here the section which allows to generate members from an initial condition which is perturbed by different means.[[BR]] |
| 263 | | |
| 264 | | There are two ways to perturb the initial condition: |
| 265 | | * apply some random white noise of defined amplitude to the temperature field of the coupler component (CPL) restart file |
| 266 | | * apply some previously generated 3D temperature perturbation map to the temperature field of the ocean component (OCE) restart file |
| 267 | | |
| 268 | | Each method applies only to the relevant type of ensemble generation available inside [Ens_PERTURB] as will be explained later. |
| 269 | | |
| 270 | | Before detailing the different functionalities available in [Ens_PERTURB] let us discuss the NAME variable.[[BR]] |
| 271 | | This variable will be both the global name of the ensemble (ie directory name) and the prefix for each member: |
| 272 | | {{{ |
| 273 | | # ensemble name |
| 274 | | NAME=v3h4testB |
| 275 | | }}} |
| 276 | | |
| 277 | | !JobName variable in `config.card` will be the name of the root directory that would be created containing all config and script files and the ensemble. |
| 278 | | |
| 279 | | === Periodic start dates === |
| 280 | | |
| 281 | | For this type of perturbed ensembles the following variables are left empty: |
| 282 | | {{{ |
| 283 | | # member list (apply list of pattern to initial state) |
| 284 | | PERTU_MAP_LIST=() |
| 285 | | |
| 286 | | # member list of names corresponding to each member |
| 287 | | MEMBER_NAMESLIST=() |
| 288 | | |
| 289 | | # member pattern global name |
| 290 | | MEMBER_INITFROM= |
| 291 | | |
| 292 | | # member pattern global directory for name |
| 293 | | MEMBER_INITPATH= |
| 294 | | ... |
| 295 | | # start dates list |
| 296 | | NONPERIODIC=() |
| 297 | | # length list for non periodic simulation (NOTE: use length above if not fill) |
| 298 | | LENGTH_NONPERIODIC=() |
| 299 | | ... |
| 300 | | # Path of Mask file |
| 301 | | MASKPATH= |
| 302 | | }}} |
| 303 | | |
| 304 | | In [#Ensemble.card ensemble.card], it is possible to specify a periodic list of start dates.[[BR]] |
| 308 | | The following part of [#Ensemble.card ensemble.card] sets 10 members from 19900101 to 20000101 every 2 years each lasting 10 years: |
| 309 | | {{{ |
| 310 | | # member nb (i.e nb of perturb initial restart for each date) |
| 311 | | MEMBER=10 |
| 312 | | ... |
| 313 | | # periodic and member list simulations length |
| 314 | | LENGTH=10Y |
| 315 | | # start date of the first ensemble |
| 316 | | BEGIN_INIT=19900101 |
| 317 | | # start date of the last ensemble |
| 318 | | END_INIT=20000101 |
| 319 | | # timestep between each periodic simulation |
| 320 | | PERIODICITY=2Y |
| 321 | | }}} |
| 322 | | |
| 323 | | This will produce 10 members starting at the dates : 19900101, 19920101, 19940101, 19960101, 19980101, 20000101. (PERIODICITY can be given in months for shorter periods) |
| 324 | | |
| 325 | | Each time the restart file to be perturbed in order to produce each member is taken from the previous day of the start date : 19893112, 19913112, etc... |
| 326 | | |
| 351 | | '''!!NOTA!! The perturbation is not applied to grid points located under the sea ice. This condition is "hard-written" in the !AddNoise code. Because of a change of the name of the sea ice cover variable from IPSL-CM5A (OIceFrac) and IPSL-CM6 (OIceFrc), a modification of the code has been made by Olivier Marti in June 2016 to allow the code to search for both names''' |
| 352 | | |
| 353 | | For each member (in our example we have ten) a new restart file for the coupler will be generated using the executable ''addnoise'' to add some randomly generated temperature perturbation.[[BR]] |
| 354 | | For the year 1990, the corresponding restart file of member 1 will be stored in |
| 355 | | {{{ |
| 356 | | $WORKDIR/IGCM_IN/v3h4testB190/v3h4testB190A/CPL/Restart/ |
| | 284 | '''NOTE :''' The perturbation is not applied to grid points located under the sea ice. [[BR]] |
| | 285 | This condition is "hard-written" in the !AddNoise code. Because of a change of the name of the sea ice cover variable from IPSL-CM5A (OIceFrac) and IPSL-CM6 (OIceFrc), a modification of the code has been made by Olivier Marti in June 2016 to allow the code to search for both names''' |
| | 286 | |
| | 287 | For each member a new restart file for the coupler will be generated using the executable ''addnoise'' to add some randomly generated temperature perturbation.[[BR]] |
| | 288 | |
| | 289 | The corresponding restart file of each member will be stored in |
| | 290 | {{{ |
| | 291 | ''Output_directory''/IGCM_IN/dcppA-hindcast/dcppA-hindcast/CPL/Restart/ |
