Hello John, > Im good with either/both axis = "ensemble" and/or > standard_name = "ensemble_member_identifier". > > for backwards compatibility, we could consider recognizing > standard_name = "realization".
do we need anything new - or is standard_name = "realization" enough? I prefer "realization" to "ensemble" as I think its a bit more neutral - for instance you can produce a set of realizations of past and future climates using detection and attribution techniques, its not clear (to me) that "ensemble" is the most natural term for these. I think the term ensemble is a bit loaded to imply a production technique, whereas realization is more descriptive of the intent. (But I'm happy to be wrong on this.) >From what I remember a lot of the issues that caused the previous discussion on ensembles to stall were around the aggregation of different files into a single ensemble file, and what you do in this case to maintain traceability back to the original model experiments. So a scenario something like: 1. There is a repository of CMIP5 integrations (a collection of mega-ensembles): a number of models, with a number of initial conditions and a number of forcing scenarios. The output from each model integration is stored in its own set of NetCDF files with global attributes likse source, forcing, experiment, model, institute, realization used to identify this data in the CMIP5 mega-ensemble. Each model can be on a different grid. 2. A data user takes all (or a selection of) the files for a mega-ensemble and puts them on the *same* space-time sampling for analysis. e.g. decadal mean global means or continent means 3. The result of the analysis may be a reduced size to the original data and so comfortably fit into one file. If the user wants to share this data with others and maitain links to the original model integrations - how do they do this? I don't know if/when we want to return to this analysis and aggregation case (is it a CF problem?). To me at least, it feels logically related to some of the discussion around station data - though I didn't follow this discussion that closely - https://cf-pcmdi.llnl.gov/trac/ticket/37#comment:34. As I understood it the problem there was 'aggregating' over instruments to for a depth coordinate, whereas here we are aggregating over model integrations to give an ensemble coordinate. Jamie > _______________________________________________ > CF-metadata mailing list > [email protected] > http://mailman.cgd.ucar.edu/mailman/listinfo/cf-metadata > _______________________________________________ CF-metadata mailing list [email protected] http://mailman.cgd.ucar.edu/mailman/listinfo/cf-metadata
