roms cmeps.yaml
The roms_cmeps.yaml file specifies the ROMS Community Mediator for Earth Prediction Systems (CMEPS) Import/Export Metadata Dictionary. Starting svn revision -r 1902 released on March 1, 2022, the ROMS coupling metadata is managed with a YAML file. The YAML files are simple, easy to follow, elegant, portable, and expandable. ROMS can now process YAML files with its parser module, yaml_parser.F. Therefore, there is no need to use third-party YAML parsers. Basically, roms_cmeps.yaml has the following structure:
project: FV3-ROMS CMEPS couping in the WATL Application
title: Hurricane Dorian Test
date: 2019-08-29T00:00:00Z # Starting date, Hurricane Dorian
forecast_length: &ForecastLength PT96H # 6 hours (ISO 8601)
coupling_step: &dt 180.0d0 # 3 minutes (PT180S)
linked_grid: 1 # linked ROMS nested grid number
ATM_component: &ATM FV3
DATA_component: data.nc
OCN_component: &OCN ROMS
CoupledSet: ESM_01
ExportState: Export_ESM_01
ImportState: Import_ESM_01
PETlayoutOption: 0
CouplingType: 2 # semi-implicit
DebugLevel: 1
TraceLevel: 0
standard_input:
OCN_component: roms_watl.in
ATM_component: namelist
state variables: [sea_surface_height_above_geoid,
barotropic_sea_water_x_velocity,
barotropic_sea_water_y_velocity,
sea_water_x_velocity,
sea_water_y_velocity,
sea_water_potential_temperature,
sea_water_practical_salinity]
export:
- standard_name: sea_surface_temperature
long_name: sea surface temperature
short_name: SST
data_variables: [temperature, time]
source_units: C
destination_units: K
source_grid: cell_center
destination_grid: cell_center
add_offset: 273.15d0
scale: 1.0d0
debug_write: false
connected_to: *OCN
map_type: mapnstod
map_norm: none
import:
- standard_name: net_downward_shortwave_flux_at_sea_water_surface
long_name: surface net shortwave radiation flux
short_name: SWrad
data_variables: [swrad, time]
source_units: W m-2
destination_units: W m-2
source_grid: cell_center
destination_grid: cell_center
add_offset: 0.0d0
scale: 1.0d0
debug_write: false
connected_to: *ATM
map_type: mapbilnr
map_norm: none
...
bulk_fluxes import:
- standard_name: net_downward_shortwave_flux_at_sea_water_surface
long_name: surface shortwave radiation flux
short_name: SWrad
data_variables: [swrad, time]
source_units: W m-2
destination_units: W m-2
source_grid: cell_center
destination_grid: cell_center
add_offset: 0.0d0
scale: 1.0d0
debug_write: false
connected_to: *ATM
map_type: mapbilnr
map_norm: none
...
The field key and value pair in the YAML blocking list is as follows:
Key | Description | ||||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|---|
standard_name | CF conventions standard name for variable. A list of applicable standard_name attributes are shown below. | ||||||||||||
long_name | The field's long descriptive name. | ||||||||||||
short_name | The field's short name private to the NUOPC cap module | ||||||||||||
data_variables | The DATA component NetCDF field and time variable names. | ||||||||||||
source_units | The field's source units. | ||||||||||||
destination_units | The field's destination units. | ||||||||||||
source_grid | The field's source grid-cell location. | ||||||||||||
destination_grid | The field's destination grid-cell location. | ||||||||||||
add_offset | The value to add to the exchanged field. | ||||||||||||
scale | The scale to use to convert data from source to destination. | ||||||||||||
debug_write | A switch indicating whether or not to write out exchanged field, if DebugLevel>2. | ||||||||||||
connected_to | The source component to which the field is connected. | ||||||||||||
regrid_method | The field regridding method from source to destination:
| ||||||||||||
extrapolate_method | The field extrapolation method for unmapped points:
|
The ESM imported fields are processed as:
- field (destination_units) = field (source_units) * scale + add_offset
YAML allows alias and anchor to avoid repetition. In YAML, single or multiple line comments start with a hash #. Also, comment after a key/value pair is allowed. All comments are skipped during processing.
Metadata: standard_name
The following table shows the standard_name attributes that are used in ROMS output NetCDF files. They follow CF conventions. However, we needed to create lots of them because are not available in the CF tables but followed their established syntax.
Variable | standard_name |
dLWrad | surface_net_downward_longwave_flux |
dSWrad | net_downward_shortwave_flux_at_sea_water_surface |
dSST | sea_surface_temperature_data |
Hair | surface_specific_humidity |
LHfx | surface_latent_heat_flux |
LWrad | surface_net_downward_longwave_flux |
Pair | surface_air_pressure |
Pmsl | mean_sea_level_pressure |
Qair | surface_relative_humidity |
rain | precipitation_flux |
shflux | surface_downward_heat_flux_in_sea_water |
SHfx | surface_sensible_heat_flux |
SST | sea_surface_temperature |
sustr | surface_downward_x_stress |
svstr | surface_downward_y_stress |
swflux | surface_upward_water_flux |
SWrad | net_shortwave_flux_at_sea_water_surface |
Tair | surface_air_temperature |
Uwind | surface_eastward_wind |
Vwind | surface_northward_wind |