Ocean and Sea Ice Observations

The [oceanObservations] and [seaIceObservations] sections of a configuration file contain options used to point to the observations files and folders:

[oceanObservations]
## options related to ocean observations with which the results will be compared

# directory where ocean observations are stored
baseDirectory = /dir/to/ocean/observations
sstSubdirectory = SST
sssSubdirectory = SSS
mldSubdirectory = MLD
ninoSubdirectory = Nino
mhtSubdirectory = MHT
meltSubdirectory = Melt
soseSubdirectory = SOSE
sshSubdirectory = SSH
argoSubdirectory = ARGO
schmidtkoSubdirectory = Schmidtko

# first and last year of SST observational climatology (preferably one of the
# two ranges given below)
# values for preindustrial
sstClimatologyStartYear = 1870
sstClimatologyEndYear = 1900
# alternative values for present day
#sstClimatologyStartYear = 1990
#sstClimatologyEndYear = 2011

# interpolation order for observations. Likely values are
#   'bilinear', 'neareststod' (nearest neighbor) or 'conserve'
interpolationMethod = bilinear

# The directories where observation climatologies will be stored if they need
# to be computed.  If a relative path is supplied, it is relative to the output
# base directory.  If an absolute path is supplied, this should point to
# cached climatology files on the desired comparison grid.  If cached remapped
# files are supplied, there is no need to provide cached files before
# remapping.
climatologySubdirectory = clim/obs
remappedClimSubdirectory = clim/obs/remapped

...

[seaIceObservations]
## options related to sea ice observations with which the results will be
## compared

# directory where sea ice observations are stored
baseDirectory = /dir/to/seaice/observations
areaNH = IceArea_timeseries/iceAreaNH_climo.nc
areaSH = IceArea_timeseries/iceAreaSH_climo.nc
volNH = PIOMAS/PIOMASvolume_monthly_climo.nc
volSH = none
concentrationNASATeamNH_JFM = SSMI/NASATeam_NSIDC0051/SSMI_NASATeam_gridded_concentration_NH_jfm.interp0.5x0.5.nc
concentrationNASATeamNH_JAS = SSMI/NASATeam_NSIDC0051/SSMI_NASATeam_gridded_concentration_NH_jas.interp0.5x0.5.nc
concentrationNASATeamSH_DJF = SSMI/NASATeam_NSIDC0051/SSMI_NASATeam_gridded_concentration_SH_djf.interp0.5x0.5.nc
concentrationNASATeamSH_JJA = SSMI/NASATeam_NSIDC0051/SSMI_NASATeam_gridded_concentration_SH_jja.interp0.5x0.5.nc
concentrationBootstrapNH_JFM = SSMI/Bootstrap_NSIDC0079/SSMI_Bootstrap_gridded_concentration_NH_jfm.interp0.5x0.5.nc
concentrationBootstrapNH_JAS = SSMI/Bootstrap_NSIDC0079/SSMI_Bootstrap_gridded_concentration_NH_jas.interp0.5x0.5.nc
concentrationBootstrapSH_DJF = SSMI/Bootstrap_NSIDC0079/SSMI_Bootstrap_gridded_concentration_SH_djf.interp0.5x0.5.nc
concentrationBootstrapSH_JJA = SSMI/Bootstrap_NSIDC0079/SSMI_Bootstrap_gridded_concentration_SH_jja.interp0.5x0.5.nc
thicknessNH_ON = ICESat/ICESat_gridded_mean_thickness_NH_on.interp0.5x0.5.nc
thicknessNH_FM = ICESat/ICESat_gridded_mean_thickness_NH_fm.interp0.5x0.5.nc
thicknessSH_ON = ICESat/ICESat_gridded_mean_thickness_SH_on.interp0.5x0.5.nc
thicknessSH_FM = ICESat/ICESat_gridded_mean_thickness_SH_fm.interp0.5x0.5.nc

# interpolation order for observations. Likely values are
#   'bilinear', 'neareststod' (nearest neighbor) or 'conserve'
interpolationMethod = bilinear

# The directories where observation climatologies will be stored if they need
# to be computed.  If a relative path is supplied, it is relative to the output
# base directory.  If an absolute path is supplied, this should point to
# cached climatology files on the desired comparison grid.  If cached remapped
# files are supplied, there is no need to provide cached files before
# remapping.
climatologySubdirectory = clim/obs
remappedClimSubdirectory = clim/obs/remapped

Files and Directories

The input directories are specified through a base directory and either subdirectories or file names for each set of observations. You will always need to set baseDirectory for both ocean and sea ice observation to a directory ending in observations/Ocean and observations/SeaIce, respectively. The rest of these paths is determined by where you downloaded the observationsal data from the E3SM public data repository (see the Quick Start Guide for details). Typically, the subdirectories and individual files will not need to be changed except for debugging purposes.

The directories for storing cached datasets before and afer remapping (specified in climatologySubdirectory and remappedClimSubdirectory) may be given any relative or absoltue path, but should typically be left as the default values.

Remapping

Observational climatologies are remapped from the native grid (typically global latitude/longitude or Antarctic stereographic) to common comparison grids. The remapping can be performed with any of three methods: bilinear, neareststod (nearest neighbor) or conserve. Mapping files are created with the ESMF_RegridWeightGen tool. The default method is bilinear and these are the mapping files distributed from the E3SM public data repository. The conseve method is know to be much slower to compute and should only be used if it is necessary (e.g. because remapped data will be checked for conservation).