5. Noah-MP Land Surface Model

This chapter provides practical information on input files and parameters for the Noah-MP Land Surface Model (LSM) and its Vector-to-Tile Converter component. For background information on the Noah-MP Land Surface Model (LSM), see Section 1.1.2 of the Introduction.

5.1. Input Files

The UFS land model requires multiple input files to run: static datasets (fix files containing climatological information, terrain, and land use data), initial conditions and forcing files, and model configuration files (such as namelists). Users may reference the Community Noah-MP User’s Guide for a detailed technical description of certain elements of the Noah-MP model.

There are several important files used to specify model parameters: the static file (ufs-land_C96_static_fields.nc), the initial conditions file (ufs-land_C96_init_*.nc), and the model configuration file (ufs-land.namelist.noahmp). These files and their parameters are described in the following subsections. They are publicly available via the Land DA Data Bucket. Users can download the data and untar the file via the command line, replacing {YEAR} with the year for the desired data. Release data is currently available for 2016 and 2020:

wget https://noaa-ufs-land-da-pds.s3.amazonaws.com/current_land_da_release_data/landda-input-data-{YEAR}.tar.gz
tar xvfz landda-input-data-{YEAR}.tar.gz

5.1.1. Static File (ufs-land_C96_static_fields.nc)

The static file includes specific information on location, time, soil layers, and fixed (invariant) experiment parameters that are required for Noah-MP to run. The data must be provided in netCDF format.

The static file is available in the inputs data directory (downloaded above) at the following path:

inputs/forcing/<source>/static/ufs-land_C96_static_fields.nc

where <source> is either gdas or era5.

Table 5.1 Configuration variables specified in the static file (ufs-land_C96_static_fields.nc)

Configuration Variables	Description
land_mask	land-sea mask (0-ocean, 1-land)
vegetation_category	vegetation type
soil_category	soil type
slope_category	slope type
albedo_monthly	monthly albedo
lai_monthly (leaf area index_monthly)	monthly leaf area index
emissivity	emissivity
z0_monthly	monthly ground roughness length
cube_tile	FV3 tile where the grid is located
cube_i	i-location in the FV3 tile where the grid is located
cube_j	j-location in the FV3 tile where the grid is located
latitude	latitude
longitude	longitude
elevation	elevation
deep_soil_temperature	lower boundary soil temperature
max_snow_albedo	maximum snow albedo
gvf_monthly	monthly green vegetation fraction (gvf)
visible_black_sky_albedo	visible black sky albedo
visible_white_sky_albedo	visible white sky albedo
near_IR_black_sky_albedo	near infrared black sky albedo
near_IR_white_sky_albedo	near infrared white sky albedo
soil_level_nodes	soil level nodes
soil_level_thickness	soil level thickness

5.1.2. Initial Conditions File (ufs-land_C96_init_*.nc)

The offline Land DA System currently only supports snow DA. The initial conditions file includes the initial state variables that are required for the UFS land snow DA to begin a cycling run. The data must be provided in netCDF format.

The initial conditions file is available in the inputs data directory (downloaded above) at the following path:

inputs/forcing/GDAS/init/ufs-land_C96_init_fields_1hr.nc
inputs/forcing/ERA5/init/ufs-land_C96_init_2010-12-31_23-00-00.nc

Table 5.2 Configuration variables specified in the initial forcing file (ufs-land_C96_init_fields_1hr.nc)

Configuration Variables	Units
time	seconds since 1970-01-01 00:00:00
date (date length)	UTC date
latitude	degrees north-south
longitude	degrees east-west
snow_water_equivalent	mm
snow_depth	m
canopy_water	mm
skin_temperature	K
soil_temperature	mm
soil_moisture	m3/m3
soil_liquid	m3/m3
soil_level_thickness	m
soil_level_nodes	m

5.1.3. Model Configuration File (ufs-land.namelist.noahmp)

The UFS land model uses a series of template files combined with user-selected settings to create required namelists and parameter files needed by the UFS Land DA workflow. This section describes the options in the ufs-land.namelist.noahmp file, which is generated from the template.ufs-noahMP.namelist.* file.

Note

Any default values indicated are the defaults set in the template.ufs-noahMP.namelist.* files.

5.1.3.1. Run Setup Parameters

static_file

Specifies the path to the UFS land static file.

init_file

Specifies the path to the UFS land initial condition file.

forcing_dir

Specifies the path to the UFS land forcing directory where atmospheric forcing files are located.

separate_output

Specifies whether to enable separate output files for each output time. Valid values: .false. | .true.

Value	Description
.false.	do not enable (should only be used for single point or short simulations)
.true.	enable

output_dir

Specifies the output directory where output files will be saved. If separate_output=.true., but no output_dir is specified, it will default to the directory where the executable is run.

restart_frequency_s

Specifies the restart frequency (in seconds) for the UFS land model.

restart_simulation

Specifies whether to enable the restart simulation. Valid values: .false. | .true.

Value	Description
.false.	do not enable
.true.	enable

restart_date

Specifies the restart date. The form is YYYY-MM-DD HH:MM:SS, where YYYY is a 4-digit year, MM is a valid 2-digit month, DD is a valid 2-digit day, HH is a valid 2-digit hour, MM is a valid 2-digit minute, and SS is a valid 2-digit second.

restart_dir

Specifies the restart directory.

timestep_seconds

Specifies the land model timestep in seconds.

simulation_start

Specifies the simulation start time. The form is YYYY-MM-DD HH:MM:SS, where YYYY is a 4-digit year, MM is a valid 2-digit month, DD is a valid 2-digit day, HH is a valid 2-digit hour, MM is a valid 2-digit minute, and SS is a valid 2-digit second.

simulation_end

Specifies the simulation end time. The form is YYYY-MM-DD HH:MM:SS, where YYYY is a 4-digit year, MM is a valid 2-digit month, DD is a valid 2-digit day, HH is a valid 2-digit hour, MM is a valid 2-digit minute, and SS is a valid 2-digit second.

run_days

Specifies the number of days to run.

run_hours

Specifies the number of hours to run.

run_minutes

Specifies the number of minutes to run.

run_seconds

Specifies the number of seconds to run.

run_timesteps

Specifies the number of timesteps to run.

5.1.3.2. Land Model Options

land_model

Specifies which land surface model to use. Valid values: 1 | 2

Value	Description
1	Noah
2	Noah-MP

5.1.3.3. Structure-Related Parameters

num_soil_levels

Specifies the number of soil levels.

forcing_height

Specifies the forcing height in meters.

5.1.3.4. Soil Setup Parameters

soil_level_thickness

Specifies the thickness (in meters) of each of the soil layers (top layer to bottom layer).

soil_level_nodes

Specifies the soil level centroids from the surface (in meters).

5.1.3.5. Noah-MP Options

dynamic_vegetation_option: (Default: 4)

Specifies the dynamic vegetation model option. Valid values: 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10

Value	Description
1	off (use table LAI; use FVEG=SHDFAC from input)
2	on (dynamic vegetation; must use Ball-Berry canopy option)
3	off (use table LAI; calculate FVEG)
4	off (use table LAI; use maximum vegetation fraction)
5	on (use maximum vegetation fraction)
6	on (use FVEG = SHDFAC from input)
7	off (use input LAI; use FVEG = SHDFAC from input)
8	off (use input LAI; calculate FVEG)
9	off (use input LAI; use maximum vegetation fraction)
10	crop model on (use maximum vegetation fraction)

LAI

Routines for handling Leaf/Stem area index data products

FVEG

Green vegetation fraction [0.0-1.0]

SHDFAC

Greenness vegetation (shaded) fraction

canopy_stomatal_resistance_option: (Default: 2)

Specifies the canopy stomatal resistance option. Valid values: 1 | 2

Value	Description
1	Ball-Berry
2	Jarvis

soil_wetness_option: (Default: 1)

Specifies the soil moisture factor for the stomatal resistance option. Valid values: 1 | 2 | 3

Value	Description
1	Noah (soil moisture)
2	CLM (matric potential)
3	SSiB (matric potential)

runoff_option: (Default: 1)

Specifies the runoff option. Valid values: 1 | 2 | 3 | 4 | 5

Value	Description
1	SIMGM: TOPMODEL with groundwater (Niu et al. [NYD+07])
2	SIMTOP: TOPMODEL with an equilibrium water table (Niu et al. [NYREDG05])
3	Noah original surface and subsurface runoff (free drainage) (Schaake et al. [SKD+96])
4	BATS surface and subsurface runoff (free drainage)
5	Miguez-Macho&Fan groundwater scheme (Miguez-Macho et al. [MMFW+07]; Fan et al. [FMMW+07])

surface_exchange_option: (Default: 3)

Specifies the surface layer drag coefficient option. Valid values: 1 | 2

Value	Description
1	Monin-Obukhov
2	original Noah (Chen 1997)

supercooled_soilwater_option: (Default: 1)

Specifies the supercooled liquid water option. Valid values: 1 | 2

Value	Description
1	no iteration (Niu and Yang [NY06])
2	Koren’s iteration (Koren et al. [KSM+99])

frozen_soil_adjust_option: (Default: 1)

Specifies the frozen soil permeability option. Valid values: 1 | 2

Value	Description
1	linear effects, more permeable (Niu and Yang [NY06])
2	nonlinear effects, less permeable (Koren et al. [KSM+99])

radiative_transfer_option: (Default: 3)

Specifies the radiation transfer option. Valid values: 1 | 2 | 3

Value	Description
1	modified two-stream (gap = F(solar angle, 3D structure…)<1-FVEG)
2	two-stream applied to grid-cell (gap = 0)
3	two-stream applied to a vegetated fraction (gap=1-FVEG)

snow_albedo_option: (Default: 2)

Specifies the snow surface albedo option. Valid values: 1 | 2

Value	Description
1	BATS
2	CLASS

precip_partition_option: (Default: 1)

Specifies the option for partitioning precipitation into rainfall and snowfall. Valid values: 1 | 2 | 3 | 4

Value	Description
1	Jordan [Jor91] (1991)
2	BATS: when SFCTMP<TFRZ+2.2
3	Noah: when SFCTMP<TFRZ
4	Use WRF microphysics output

SFCTMP

Surface air temperature

TFRZ

Freezing/melting point (K)

soil_temp_lower_bdy_option: (Default: 2)

Specifies the lower boundary condition of soil temperature option. Valid values: 1 | 2

Value	Description
1	zero heat flux from the bottom (ZBOT and TBOT not used)
2	TBOT at ZBOT (8m) read from a file (original Noah)

TBOT

Lower boundary soil temperature [K]

ZBOT

Depth[m] of lower boundary soil temperature (TBOT)

soil_temp_time_scheme_option: (Default: 3)

Specifies the snow and soil temperature time scheme. Valid values: 1 | 2 | 3

Value	Description
1	semi-implicit; flux top boundary condition
2	fully implicit (original Noah); temperature top boundary condition
3	same as 1, but FSNO for TS calculation (generally improves snow; v3.7)

FSNO

Fraction of surface covered with snow

TS

Surface temperature

thermal_roughness_scheme_option: (Default: 2)

Specifies the method/scheme used to calculate the thermal roughness length. Valid values: 1 | 2 | 3 | 4

Value	Description
1	z0h=z, thermal roughness length = momentum roughness length
2	czil, use canopy height method based on (Chen and Zhang [CZ09])
3	European Center method
4	kb inverse method

surface_evap_resistance_option: (Default: 1)

Specifies the surface evaporation resistance option. Valid values: 1 | 2 | 3 | 4

Value	Description
1	Sakaguchi and Zeng [SZ09]
2	Sellers et al. [SMDHH92]
3	adjusted Sellers to decrease RSURF for wet soil
4	option 1 for non-snow; rsurf = rsurf_snow for snow

rsurf

Ground surface resistance (s/m)

glacier_option: (Default: 1)

Specifies the glacier model option. Valid values: 1 | 2

Value	Description
1	include phase change of ice
2	simple (ice treatment more like original Noah)

5.1.3.6. Forcing Parameters

forcing_timestep_seconds: (Default: 3600)

Specifies the forcing timestep in seconds.

forcing_type

Specifies the forcing type option, which describes the frequency and length of forcing in each forcing file. Valid values: single-point | gswp3 | gdas

Value	Description
single-point	All forcing times are in one file
gswp3	three-hourly forcing stored in monthly files
gdas	hourly forcing stored in daily files

Note

There is no separate era5 format. It is the same as the gdas format, so users should select gdas for this parameter when using era5 forcing.

forcing_filename

Specifies the forcing file name prefix. A date will be appended to this prefix. For example: C96_ERA5_forcing_2020-10-01.nc. The prefix merely indicates which grid (C96) and source (i.e., GDAS, GEFS) will be used. Common values include: C96_GDAS_forcing_ | C96_ERA5_forcing_ | C96_GEFS_forcing_ | C96_GSWP3_forcing_

Value	Description
C96_GDAS_forcing_	GDAS forcing data for a C96 grid
C96_ERA5_forcing_	ERA5 forcing data for a C96 grid
C96_GEFS_forcing_	GEFS forcing data for a C96 grid
C96_GSWP3_forcing_	GSWP3 forcing data for a C96 grid

forcing_interp_solar

Specifies the interpolation option for solar radiation. Valid values: linear | gswp3_zenith

Value	Description
linear	Performs a linear interpolation between forcing times
gswp3_zenith	Performs a cosine zenith angle interpolation between forcing times

forcing_time_solar

Valid values include: "instantaneous" | "gswp3_average"

forcing_name_precipitation

Specifies the variable name of forcing precipitation. Valid values include: "precipitation_conserve" | "precipitation_bilinear"

forcing_name_temperature``(Default: ``"temperature")

Specifies the variable name of forcing temperature.

forcing_name_specific_humidity: (Default: "specific_humidity")

Specifies the variable name of forcing specific-humidity.

forcing_name_wind_speed: (Default: "wind_speed")

Specifies the variable name of forcing wind speed.

forcing_name_pressure: (Default: "surface_pressure")

Specifies the variable name of forcing surface pressure.

forcing_name_sw_radiation: (Default: "solar_radiation")

Specifies the variable name of forcing shortwave radiation.

forcing_name_lw_radiation: (Default: "longwave_radiation")

Specifies the variable name of forcing longwave radiation.

5.1.3.7. Example Namelist Entry

The ufs-land.namelist.noahmp file should be similar to the following example, which comes from the template.ufs-noahMP.namelist.gdas file.

&run_setup

   static_file      = "/LANDDA_INPUTS/forcing/gdas/static/ufs-land_C96_static_fields.nc"
   init_file        = "/LANDDA_INPUTS/forcing/gdas/init/ufs-land_C96_init_fields_1hr.nc"
   forcing_dir      = "/LANDDA_INPUTS/forcing/gdas/gdas/forcing"

   separate_output = .false.
   output_dir       = "./"

   restart_frequency_s = XXFREQ
   restart_simulation  = .true.
   restart_date        = "XXYYYY-XXMM-XXDD XXHH:00:00"
   restart_dir         = "./"

   timestep_seconds = 3600

! simulation_start is required
! either set simulation_end or run_* or run_timesteps, priority
!   1. simulation_end 2. run_[days/hours/minutes/seconds] 3. run_timesteps

   simulation_start = "2000-01-01 00:00:00"   ! start date [yyyy-mm-dd hh:mm:ss]
   ! simulation_end   = "1999-01-01 06:00:00"   !   end date [yyyy-mm-dd hh:mm:ss]

   run_days         = XXRDD   ! number of days to run
   run_hours        = XXRHH   ! number of hours to run
   run_minutes      = 0       ! number of minutes to run
   run_seconds      = 0       ! number of seconds to run

   run_timesteps    = 0       ! number of timesteps to run

   location_start   = 1
   location_end     = 18360

/

&land_model_option
   land_model        = 2   ! choose land model: 1=noah, 2=noahmp
/

&structure
   num_soil_levels   = 4     ! number of soil levels
   forcing_height    = 6     ! forcing height [m]
/

&soil_setup
   soil_level_thickness   =  0.10,    0.30,    0.60,    1.00      ! soil level thicknesses [m]
   soil_level_nodes       =  0.05,    0.25,    0.70,    1.50      ! soil level centroids from surface [m]
/

&noahmp_options
   dynamic_vegetation_option         = 4
   canopy_stomatal_resistance_option = 2
   soil_wetness_option               = 1
   runoff_option                     = 1
   surface_exchange_option           = 3
   supercooled_soilwater_option      = 1
   frozen_soil_adjust_option         = 1
   radiative_transfer_option         = 3
   snow_albedo_option                = 2
   precip_partition_option           = 1
   soil_temp_lower_bdy_option        = 2
   soil_temp_time_scheme_option      = 3
   thermal_roughness_scheme_option   = 2
   surface_evap_resistance_option    = 1
   glacier_option                    = 1
/

&forcing
   forcing_timestep_seconds       = 3600
   forcing_type                   = "gdas"
   forcing_filename               = "C96_GDAS_forcing_"
   forcing_interp_solar           = "linear"  ! gswp3_zenith or linear
   forcing_time_solar             = "instantaneous"  ! gswp3_average or instantaneous
   forcing_name_precipitation     = "precipitation_conserve"
   forcing_name_temperature       = "temperature"
   forcing_name_specific_humidity = "specific_humidity"
   forcing_name_wind_speed        = "wind_speed"
   forcing_name_pressure          = "surface_pressure"
   forcing_name_sw_radiation      = "solar_radiation"
   forcing_name_lw_radiation      = "longwave_radiation"
/

5.2. Vector-to-Tile Converter

The Vector-to-Tile Converter is used for mapping between the vector format used by the Noah-MP offline driver and the tile format used by the UFS atmospheric model. This converter is currently used to prepare input tile files for JEDI. Note that these files include only those fields required by JEDI, rather than the full restart.

5.2.1. Input File

The input files containing grid information are listed in Table 5.3:

Table 5.3 Input Files Containing Grid Information

Filename	Description
Cxx_grid.tile[1-6].nc	Cxx grid information for tiles 1-6, where xx is the grid resolution.
Cxx_oro_data.tile[1-6].nc / oro_Cxx.mx100.tile[1-6].nc	Orography files that contain grid and land mask information. Cxx refers to the atmospheric resolution, and mx100 refers to the ocean resolution (100=1º). Both file names refer to the same file; there are symbolic links between them.

5.2.2. Configuration File

This section describes the options in the namelist.vector2tile file.

5.2.2.1. Run Setup Parameters

direction

Specifies the conversion option. Valid values: vector2tile | tile2vector | lndp2tile | lndp2vector

Value	Description
vector2tile	vector-to-tile conversion for restart file
tile2vector	tile-to-vector conversion for restart file
lndp2tile	land perturbation to tile
lndp2vector	land perturbation to vector

5.2.2.2. FV3 Tile-Related Parameters for Restart/Perturbation Conversion

Parameters in this section include the FV3 resolution and path to orographic files for restart/perturbation conversion.

tile_size

Specifies the size (horizontal resolution) of the FV3 tile. Valid values: 96.

Note

• The C96 grid files correspond to approximately 1º latitude/longitude.

• Additional resolutions (e.g., 192, 384, 768) are under development.

tile_path

Specifies the path to the orographic tile files.

tile_fstub

Specifies the name (file stub) of orographic tile files. The file stub will be named oro_C${RES} for atmosphere-only and oro_C{RES}.mx100 for atmosphere and ocean.

5.2.2.3. Parameters for Restart Conversion

These parameters apply only to restart conversion.

static_filename

Specifies the path for static file.

vector_restart_path

Specifies the location of vector restart file, vector-to-tile direction.

tile_restart_path

Specifies the location of tile restart file, tile-to-vector direction.

output_path

Specifies the path for converted files. If this is same as tile/vector path, the files may be overwritten.

5.2.2.4. Perturbation Mapping Parameters

These parameters are only relevant for perturbation mapping in ensembles. Support for ensembles is not provided for the Land DA v1.0.0 release.

lndp_layout

Specifies the layout options. Valid values: 1x4 | 4x1 | 2x2

lndp_input_file

Specifies the path for the input file.

output files

Specifies the path for the output file.

lndp_var_list

Specifies the land perturbation variable options. Valid values: vgf | smc

Value	Description
vgf	Perturbs the vegetation green fraction
smc	Perturbs the soil moisture

5.2.2.5. Example of a namelist.vector2tile Entry

&run_setup

direction = "vector2tile"

&FV3 resolution and path to oro files for restart/perturbation
conversion

tile_size = 96
tile_path ="/ /"
tile_fstub = "oro_C96.mx100"

!------------------- only restart conversion -------------------

! Time stamp for conversion for restart conversion
restart_date = "2019-09-30 23:00:00"

! Path for static file
static_filename="/*/filename.nc "

! Location of vector restart file (vector2tile direction)
vector_restart_path ="/ /"

! Location of tile restart files (tile2vector direction)
tile_restart_path ="/ /"

output_path ="/ /"

!------------------- only perturbation mapping -------------------
lndp_layout = "1x4"

! input files
lndp_input_file ="/*/filename.nc "

! output files
lndp_output_file = "./output.nc"

! land perturbation variable list
lndp_var_list='vgf','smc'