CDO

Hello there,

It seems that mergetime merge data regardless of which variables are being merged. For instance:
cdo mergetime mrro_day_MPI-ESM-LR_amip_r1i1p1_19790101-20081231.nc tslsi_day_MPI-ESM-LR_amip_r1i1p1_19790101-20081231.nc o.nc

where
time = UNLIMITED ; // (10958 currently) for mrro
and
time = UNLIMITED ; // (10958 currently) for tslsi

produces (ncdump -h of o.nc):

dimensions:
lon = 192 ;
nb2 = 2 ;
lat = 96 ;
time = UNLIMITED ; // (21916 currently)
variables:
double lon(lon) ;
lon:standard_name = "longitude" ;
lon:long_name = "longitude" ;
lon:units = "degrees_east" ;
lon:axis = "X" ;
lon:bounds = "lon_bnds" ;
double lon_bnds(lon, nb2) ;
double lat(lat) ;
lat:standard_name = "latitude" ;
lat:long_name = "latitude" ;
lat:units = "degrees_north" ;
lat:axis = "Y" ;
lat:bounds = "lat_bnds" ;
double lat_bnds(lat, nb2) ;
double time(time) ;
time:standard_name = "time" ;
time:bounds = "time_bnds" ;
time:units = "days since 1979-01-01 00:00:00" ;
time:calendar = "proleptic_gregorian" ;
double time_bnds(time, nb2) ;
time_bnds:units = "days since 1979-01-01 00:00:00" ;
time_bnds:calendar = "proleptic_gregorian" ;
float mrro(time, lat, lon) ;
mrro:standard_name = "runoff_flux" ;
mrro:long_name = "Total Runoff" ;
mrro:units = "kg m-2 s-1" ;
mrro:grid_type = "gaussian" ;
mrro:_FillValue = 1.e+20f ;
mrro:comment = "\"computed as the total runoff (including \"\"drainage\"\" through the base of the soil model) leaving the land portion of the grid cell divided by the land area in the grid cell.\"" ;
mrro:cell_methods = "time: mean area: mean where land" ;
mrro:associated_files = "baseURL: http://cmip-pcmdi.llnl.gov/CMIP5/dataLocation gridspecFile: gridspec_land_fx_MPI-ESM-LR_amip_r0i0p0.nc areacella: areacella_fx_MPI-ESM-LR_amip_r0i0p0.nc" ;

// global attributes:
:CDI = "Climate Data Interface version 1.5.8 (http://code.zmaw.de/projects/cdi)" ;
:Conventions = "CF-1.4" ;
:history = "Tue Jan 21 11:28:52 2014: cdo mergetime mrro_day_MPI-ESM-LR_amip_r1i1p1_19790101-20081231.nc tslsi_day_MPI-ESM-LR_amip_r1i1p1_19790101-20081231.nc lixo.nc\n",
"Model raw output postprocessing with modelling environment (IMDI) at DKRZ: URL: http://svn-mad.zmaw.de/svn/mad/Model/IMDI/trunk, REV: 3135 2011-05-26T14:06:25Z CMOR rewrote data to comply with CF standards and CMIP5 requirements." ;
:institution = "Max Planck Institute for Meteorology" ;
:institute_id = "MPI-M" ;
:experiment_id = "amip" ;
:model_id = "MPI-ESM-LR" ;
:forcing = "GHG Oz SD Sl Vl LU" ;
:parent_experiment_id = "N/A" ;
:parent_experiment_rip = "N/A" ;
:branch_time = 0. ;
:contact = "cmip5-mpi-esm@dkrz.de" ;
:references = "ECHAM6: n/a; JSBACH: Raddatz et al., 2007. Will the tropical land biosphere dominate the climate-carbon cycle feedback during the twenty first century? Climate Dynamics, 29, 565-574, doi 10.1007/s00382-007-0247-8;" ;
:initialization_method = 1 ;
:physics_version = 1 ;
:tracking_id = "29fd1d07-1f4b-45e4-94a2-049b34bbe614" ;
:product = "output" ;
:experiment = "AMIP" ;
:frequency = "day" ;
:creation_date = "2011-05-26T14:06:25Z" ;
:project_id = "CMIP5" ;
:table_id = "Table day (27 April 2011) 86d1558d99b6ed1e7a886ab3fd717b58" ;
:title = "MPI-ESM-LR model output prepared for CMIP5 AMIP" ;
:parent_experiment = "N/A" ;
:modeling_realm = "land" ;
:realization = 1 ;
:cmor_version = "2.5.9" ;
:CDO = "Climate Data Operators version 1.5.8 (http://code.zmaw.de/projects/cdo)"

which means that cdo stored under mrro both mrro and tslsi.

Cheers,
Eduardo

Data can be find here:
http://bmbf-ipcc-ar5.dkrz.de/thredds/esgcet/1/cmip5.output1.MPI-M.MPI-ESM-LR.amip.day.land.day.r1i1p1.v20111005.html?dataset=cmip5.output1.MPI-M.MPI-ESM-LR.amip.day.land.day.r1i1p1.v20111005.mrro_day_MPI-ESM-LR_amip_r1i1p1_19790101-20081231.nc_0
http://bmbf-ipcc-ar5.dkrz.de/thredds/esgcet/1/cmip5.output1.MPI-M.MPI-ESM-LR.amip.day.land.day.r1i1p1.v20111005.html?dataset=cmip5.output1.MPI-M.MPI-ESM-LR.amip.day.land.day.r1i1p1.v20111005.tslsi_day_MPI-ESM-LR_amip_r1i1p1_19790101-20081231.nc_0