SQG
Attention
sqg works with versions of DART before Manhattan (9.x.x) and has yet to be updated. If you are interested in
using sqg with more recent versions of DART, contact DAReS staff to assess the feasibility of an update.
Until that time, you should consider this documentation as out-of-date.
Overview
This is a uniform PV two-surface QG+1 spectral model contributed by Rahul Majahan.
The underlying model is described in: Hakim, Gregory J., 2000: Role of Nonmodal Growth and Nonlinearity in Cyclogenesis Initial-Value Problems. J. Atmos. Sci., 57, 2951-2967. doi: 10.1175/1520-0469(2000)057<2951:RONGAN>2.0.CO;2
Other modules used
types_mod
time_manager_mod
threed_sphere/location_mod
utilities_mod
Public interfaces
use model_mod, only : |
get_model_size |
adv_1step |
|
get_state_meta_data |
|
model_interpolate |
|
get_model_time_step |
|
static_init_model |
|
end_model |
|
init_time |
|
init_conditions |
|
nc_write_model_atts |
|
nc_write_model_vars |
|
pert_model_state |
|
get_close_maxdist_init |
|
get_close_obs_init |
|
get_close_obs |
|
ens_mean_for_model |
Optional namelist interface &model_nml may be read from file input.nml.
A note about documentation style. Optional arguments are enclosed in brackets [like this].
model_size = get_model_size( )
integer :: get_model_size
Returns the length of the model state vector.
|
The length of the model state vector. |
call adv_1step(x, time)
real(r8), dimension(:), intent(inout) :: x
type(time_type), intent(in) :: time
Advances the model for a single time step. The time associated with the initial model state is also input although it is not used for the computation.
|
State vector of length model_size. |
|
Specifies time of the initial model state. |
call get_state_meta_data (index_in, location, [, var_type] )
integer, intent(in) :: index_in
type(location_type), intent(out) :: location
integer, optional, intent(out) :: var_type
Returns metadata about a given element, indexed by index_in, in the model state vector. The location defines where the state variable is located.
|
Index of state vector element about which information is requested. |
|
The location of state variable element. |
var_type |
Returns the type (always 1) of the indexed state variable as an optional argument. |
call model_interpolate(x, location, itype, obs_val, istatus)
real(r8), dimension(:), intent(in) :: x
type(location_type), intent(in) :: location
integer, intent(in) :: itype
real(r8), intent(out) :: obs_val
integer, intent(out) :: istatus
Given model state, returns the value interpolated to a given location.
|
A model state vector. |
|
Location to which to interpolate. |
|
Not used. |
|
The interpolated value from the model. |
|
Quality control information, always returned 0. |
var = get_model_time_step()
type(time_type) :: get_model_time_step
Returns the time step (forecast length) of the model;
|
Smallest time step of model. |
call static_init_model()
Used for runtime initialization of model; reads namelist, initializes model parameters, etc. This is the first call made to the model by any DART-compliant assimilation routine.
call end_model()
A stub.
call init_time(time)
type(time_type), intent(out) :: time
Returns the time at which the model will start if no input initial conditions are to be used. This is used to spin-up the model from rest.
|
Initial model time. |
call init_conditions(x)
real(r8), dimension(:), intent(out) :: x
Returns default initial conditions for the model; generally used for spinning up initial model states.
|
Initial conditions for state vector. |
ierr = nc_write_model_atts(ncFileID)
integer :: nc_write_model_atts
integer, intent(in) :: ncFileID
Function to write model specific attributes to a netCDF file. At present, DART is using the NetCDF format to output diagnostic information. This is not a requirement, and models could choose to provide output in other formats. This function writes the metadata associated with the model to a NetCDF file opened to a file identified by ncFileID.
|
Integer file descriptor to previously-opened netCDF file. |
|
Returns a 0 for successful completion. |
ierr = nc_write_model_vars(ncFileID, statevec, copyindex, timeindex)
integer :: nc_write_model_vars
integer, intent(in) :: ncFileID
real(r8), dimension(:), intent(in) :: statevec
integer, intent(in) :: copyindex
integer, intent(in) :: timeindex
Writes a copy of the state variables to a netCDF file. Multiple copies of the state for a given time are supported, allowing, for instance, a single file to include multiple ensemble estimates of the state.
|
file descriptor to previously-opened netCDF file. |
|
A model state vector. |
|
Integer index of copy to be written. |
|
The timestep counter for the given state. |
|
Returns 0 for normal completion. |
call pert_model_state(state, pert_state, interf_provided)
real(r8), dimension(:), intent(in) :: state
real(r8), dimension(:), intent(out) :: pert_state
logical, intent(out) :: interf_provided
Given a model state, produces a perturbed model state.
|
State vector to be perturbed. |
|
Perturbed state vector: NOT returned. |
|
Returned false; interface is not implemented. |
call get_close_maxdist_init(gc, maxdist)
type(get_close_type), intent(inout) :: gc
real(r8), intent(in) :: maxdist
Pass-through to the 3D Sphere locations module. See get_close_maxdist_init() for the documentation of this subroutine.
call get_close_obs_init(gc, num, obs)
type(get_close_type), intent(inout) :: gc
integer, intent(in) :: num
type(location_type), intent(in) :: obs(num)
Pass-through to the 3D Sphere locations module. See get_close_obs_init() for the documentation of this subroutine.
call get_close_obs(gc, base_obs_loc, base_obs_kind, obs, obs_kind, num_close, close_ind [, dist])
type(get_close_type), intent(in) :: gc
type(location_type), intent(in) :: base_obs_loc
integer, intent(in) :: base_obs_kind
type(location_type), intent(in) :: obs(:)
integer, intent(in) :: obs_kind(:)
integer, intent(out) :: num_close
integer, intent(out) :: close_ind(:)
real(r8), optional, intent(out) :: dist(:)
Pass-through to the 3D Sphere locations module. See get_close_obs() for the documentation of this subroutine.
call ens_mean_for_model(ens_mean)
real(r8), dimension(:), intent(in) :: ens_mean
A NULL INTERFACE in this model.
|
State vector containing the ensemble mean. |
Namelist
We adhere to the F90 standard of starting a namelist with an ampersand ‘&’ and terminating with a slash ‘/’ for all our namelist input.
&model_nml
output_state_vector = .false.
channel_center = 45.0
channel_width = 40.0
assimilation_period_days = 0
assimilation_period_seconds = 21600
debug = .false.
/
This namelist is read in a file called input.nml
Contents |
Type |
Description |
|---|---|---|
output_state_vector |
logical |
If .true. write state vector as a 1D array to the diagnostic output file. If .false. break state vector up into fields before writing to the outputfile. |
channel_center |
real(r8) |
Channel center |
channel_width |
real(r8) |
Channel width |
assimilation_period_days |
integer |
Number of days for timestep |
assimilation_period_seconds |
integer |
Number of seconds for timestep |
debug |
logical |
Set to .true. for more output |
Files
filename |
purpose |
|---|---|
input.nml |
to read the model_mod namelist |
preassim.nc |
the time-history of the model state before assimilation |
analysis.nc |
the time-history of the model state after assimilation |
dart_log.out [default name] |
the run-time diagnostic output |
dart_log.nml [default name] |
the record of all the namelists actually USED - contains the default values |
References
Private components
N/A