Input Parameters:
Lists input parameters and tables explaining options.| Parameter | Type | Description | Units | Argument Number |
| dyn_in_prm | int | Dynamic input parameter index | none | 1 |
| dyn_in_val | float | Dynamic input value. Usually the mean wind speed at the height (zref) of the anemometer. Other input options are friction velocity (magnitude), wind stress (magnitude), and equivalent neutral wind speed (scatterometer wind speed). Altnernatively, this value can be a vector component of the wind (or other such inputs). It should be a vector component in the direction of wave propagation. In a future release, I plan on allowing this to be the u-compoent,. | see below | 2 |
| dyn_in_val2 | float | Dynamic input value 2. This value is usually zero because magnitude of the wind is often entered in dyn_in_val. If a vector component is entered in dyn_in_val, then dyn_in_val is the other vector component. | see below | 2 |
| CONVECT | float | Convective parameter. Recommended value between 0.7 and 1.25. For details see TOGA NOTES #4 | none | 4 |
| CONV_CRIT | float | Convergence criterion | fraction | 5 |
| pressure | float | Atmospheric surface pressure. Note that the 2nd most common error in data entry is to enter this value with the wrong units; don't use mb or hPa. | Pa | 6 |
| air_moist_prm | int | Atmospheric moisture parameter index | none | 7 |
| air_moist_val | float | Value of the parameter corresponding to the above index | see below | 8 |
| sfc_moist_prm | int | Surface moisture parameter index | none | 9 |
| sfc_moist_val | float | Value of the parameter corresponding to the above index | see below | 10 |
| salinity | float | Salinity. Enter as a fraction (e.g., 0.0349) rather than parts per thousand | none | 11 |
| ss_prm | int | Seastate parameter index | none | 12 |
| ss_val | float | Value of the parameter corresponding to the above index | see below | 13 |
| t_air | float | Air temperature at the reference height of the thermometer and humidity sensor | C | 14 |
| t_skin | float | Skin temperature of the water. | C | 15 |
| ref_ht_wind | float | Height of the wind observations | m | 16 |
| ref_ht_tq | float | Height of the temperature observations. Note: in the current version of the code this must equal to height of the humidity observations. | m | 17 |
| astab | int | Atmospheric stability option | none | 18 |
| flux_model | int | Warning level: 0 warnings, 1 no warnings. | none | 19 |
| z0_mom_prm | int | Momentum roughness length parameterization. To use this input, flux_model must have a value less than zero. | none | 20 |
| z0_TQ_prm | int | Potential temperature and moisture roughness length parameterization. To use this input, flux_model must have a value less than zero. | none | 21 |
| stable_prm | int | Stability parameterization. If astab=0 (neutral stability) then this setting has no influence. Furthermore, flux_model must have a value less than zero. | none | 22 |
Options for dynamic input:
Typically wind speed is used as an input to boundary-layer models. However, scatterometers are now
producing 'observations' of friction velocity and equivelent neutral wind speed.
| dyn_in | Description | Units |
| 0 | Wind speed, relative to the surface current | m/s |
| 1 | Friction velocity (magnitude) | m/s |
| 2 | Surface wind stress (magnitude) | N/m^2 |
| 3 | Equivalent neutral wind speed (relative to the surface current) | m/s |
Options for atmospheric stability condition:
The atmospheric stability in the boundary-layer can be assumed
to neutral, or it can be calculated input parameters.
| astab | Description | Units |
| 0 | Atmospheric stability is assumed to be neutral | none |
| 1 | Stability is calculated | none |
Options for seastate parameterizations:
There are six possible seastate assumptions: any one of the
following can be treated as known: wind-wave stability parameter
(set to 1.0 for local equilibrium), phase speed, wave age, significant wave height, significant slope, and the period of the dominant waves.
Caution: in many cases, these wave characteristics will correspond to swell rather than the phase speed of locally wind induced waves.
| ss_prm | Parameter treated as known (ss_val) | Units |
| 0 | Wind-wave stability parameter | none |
| 1 | Phase speed of the dominant waves. Note: in many cases, this phase speed will correspond to the swell rather than the phase speed of locally wind induced waves. Use of the wrong phase speed can lead to large overestimations of fluxes. | m/s |
| 2 | Wave age the dominant waves (cp/u*) | none |
| 3 | Significant wave height (Hs) | m |
| 4 | Significant slope (Hs/l) | none |
| 5 | Period of the dominant waves (Tp) | s |
Options for atmospheric moisture input:
Choose the moisture parameter that is easiest for you to deal
with:
| air_moist_prm | Parameter for moisture of air (air_moist_val) | Units |
| 0 | Specific humidity at the reference height of the thermometer and humidity sensor | g vapor / g air |
| 1 | Relative humidity | fraction |
| 2 | Dew point temperature | C |
| 3 | Wet bulb temperature | C |
Options for surface moisture input:
Choose the moisture parameter that is easiest for you to deal
with:
| sfc_moist_prm | Parameter for moisture of air (sfc_moist_val) | Units |
| 0 | Specific humidity 'at' (near) the surface | g vapor / g air |
| 1 | Relative humidity | fraction |
| 2 | Dew point temperature | C |
| 3 | Wet bulb temperature | C |
Options for selecting parameterizations to match published flux models:
| flux_model | Parameter for moisture of air (sfc_moist_val) |
| 0 | The flux_model variable is not used. Instead, the parameterizations are selected using three variables: z0_mom_prm, z0_TQ_prm, and stable_prm. |
| 1 | Bourassa, Vincent and Wood (1999, JAS) |
| 2 | Smith (1988, JGR) version based on a momentum roughness length being a sum of roughesses for a smooth surface and gravity waves (Charnock's constant = 0.011. |
| 3 | BVW (1999) with Smith (1988) stability parameterization. |
| 4 | BVW (1999) without roughness from capillary waves. |
| 5 | BVW (1999) without surface tension in phase speed parameterizaiton. |
| 6 | BVW (1999) without roughness from capillary waves, and without surface tension in phase speed parameterizaiton. |
| 7 | Taylor and Yelland (2001, JTECH) parameterization. |
| 8 | Taylor and Yelland (2001, JTECH) parameterization with additional momentum roughness length due to capillary waves. |
| 9 | Bourassa (2006) roughness length parameterization and CFC (Clayson, Fairall, and Curry) roughness length parameterization for potential temperature and moisture. |
| 10 | Bourassa (2006) roughness length parameterization and CFC (Clayson, Fairall, and Curry) roughness length parameterization for potential temperature and moisture, and a displacement height of 80% of the significant wave height. This assumption about displacement height works for wind driven waves; however, a displacement height of zero is a better assumption for swell. |
| 11 | Bourassa (2006) roughness length parameterization and Zilitinkevich et al. roughness length parameterization for potential temperature and moisture. |
| 12 | Bourassa (2006) roughness length parameterization and LKB (Liu, Katsaros, and Businger; 1979; JAS) roughness length parameterization for potential temperature and moisture. |
| 13 | Bourassa (2006) roughness length parameterization and COARE3.0 (ref) roughness length parameterization for potential temperature and moisture. |
| 14 | Bourassa (2006) roughness length parameterization and wall theory roughness length parameterization for potential temperature and moisture. |
| 15 | Bourassa (2006) roughness length parameterization and CFC (Clayson, Fairall, and Curry) roughness length parameterization for potential temperature and moisture. The surface is also considered to be covered with oil modeled after the DWH spill. |
Roughness Length Options for Momentum:
This option is applied only if flux_model < 0.
| z0_mom_prm | Parameterizaton for Momentum Roughness Length (z0_mom_prm) |
| 0 | Bourassa, Vincent and Wood (1999, JAS) momentum roughness length parameterization. |
| 1 | Bourassa (2006) momentum roughness length parameterization. |
| 2 | Taylor and Yelland (1999, JTECH) momentum roughness length parameterization. |
| 3 | Bourassa (2006) momentum roughness length parameterization modified for an oil slick modeled after the DWH slick. |
Roughness Length Options for Potential Temperature and Moisture:
This option is applied only if flux_model < 0. Note that the potential temperature and moisture roughness lengths are calculated separately; however, the type of parameterization comes from the same source.
| z0_mom_prm | Parameterizaton Type for Potential Temperature and Moisture Roughness Length (z0_mom_prm) |
| 0 | CFC (Clayson, Fairall and Curry; 1996, JGR) parameterization. |
| 1 | Zilitinkevich et al. (2001) roughness length parameterization. |
| 2 | LKB (Liu, Katsaros, and Businger; 1979, JAS) parameterization. |
Boundary-Layer Stability Options:
This option is applied only if flux_model < 0.
| stable_prm | Parameterizaton Type for Boundary-Layer Stability (stable_prm) |
| 0 | BVW (Bourassa, Vincent and Wood; 1999; JAS) collection of parameterizations. |
| 1 | Smith (1988; JGR) collection of parameterizations. |
Model Output:
Vector components are calculated parallel and perpendicular to
the direction in which the dominant waves are propagating. The
first component is parallel the direction of wave
propagation, and the second component is perpendicular to the
first (while looking down it is 90 counter-clockwise from the
first component; i.e., in a right handed coordinate system with
the positive vertical axis pointing upward). For most applications
there will be insufficient wave information, requiring the assumption
of local wind-wave equilibrium. This assumption implies that
the wind and the waves are moving in the same direction; which
results in the first component of the vectors being parallel to
the wind direction, and the second component being zero.
All output is single precision floating point.
The routine returns a integer value (i.e., a warning flag). Positive values indicate a lack of specific problems.
If there are problems with missing input, non-convergence within the algorithm, or if the modeled physics obviously fails to apply, then the output is set to -1.
For example, if the thickness of the boundary layer is too small (i.e., the absolute value of the Obhukov scale length less than or equal to 1 m) then the warning flag is set at -1.
| Parameter | Type | Description | Units | Argument Number |
| shf | float | sensible heat flux | W m-2 | 23 |
| lhf | float | latent heat flux | W m-2 | 24 |
| tau | vector float | stress vector. There are more details on the conversion to zonal and meridional components. | N m-2 | 25 |
| u_star | vector float | friction velocity (u*) | m s-1 | 26 |
| t_star | float | scaling term for potential temperature (T*) | C | 27 |
| q_star | float | scaling parameter for moisture (q*) | none | 28 |
| z_over_L | float | dimensionless Monin-Obhukov scale length | none | 29 |
| wave_age | float | wave age, cp/u* | none | 30 |
| dom_phs_spd | float | phase speed of dominant gravity waves | m s-1 | 31 |
| h_sig | float | significant wave height | m | 32 |
| ww_stab | float | wind-wave evolution parameter | none | 33 |
| zo_m | vector float | momentum roughness length | m | 34 |
Last update: Sept. 20, 2012
