396 | | Gradient(s) of the profile for the large scale subsidence/ascent velocity (in (m/s) / 100 m). |
397 | | |
398 | | This gradient holds starting from the height level defined by ws_vertical_gradient_level (precisely: for all uv levels k where zu(k) > ws_vertical_gradient_level, w_subs(k) is set: w_subs(k) = w_subs(k-1) + dzu(k) * ws_vertical_gradient) up to the top boundary or up to the next height level defined by ws_vertical_gradient_level. A total of 10 different gradients for 11 height intervals (10 intervals if ws_vertical_gradient_level(1) = 0.0) can be assigned. |
399 | | |
400 | | Example: |
401 | | |
402 | | ws_vertical_gradient = -0.002, 0.0, |
403 | | ws_vertical_gradient_level = 0.0, 1000.0, |
404 | | |
405 | | That defines the subsidence/ascent profile to be linear up to z = 1000.0 m with a surface value of 0 m/s. For z > 1000.0 m up to the top boundary the gradient is 0.0 (m/s) / 100 m (it is assumed that the assigned height levels correspond with uv levels). |
406 | | |
407 | | With an appropriate construction of w_subs the height of the boundary layer z_i can be kept approximately constant. |
408 | | |
409 | | Attention: |
410 | | The large scale vertical motion is only applied to the prognostic equation for the scalar quantities (potential temperature, humidity if humidity = .T. or passive scalar if passive_scalar = .T.) because it cannot be applied to the momentum equations due to incompressibility. Thus, the model is not mass consistent. |
| 395 | Gradient(s) of the profile for the large scale subsidence/ascent velocity (in (m/s) / 100 m).\\\\ |
| 396 | This gradient holds starting from the height level defined by [#ws_vertical_gradient_level ws_vertical_gradient_level] (precisely: for all uv levels k where zu(k) > ws_vertical_gradient_level, '''w_subs'''(k) is set: w_subs(k) = w_subs(k-1) + dzu(k) * '''ws_vertical_gradient''') up to the top boundary or up to the next height level defined by ws_vertical_gradient_level. A total of 10 different gradients for 11 height intervals (10 intervals if ws_vertical_gradient_level(1) = 0.0) can be assigned.\\\\ |
| 397 | '''Example:'''\\\\ |
| 398 | '''ws_vertical_gradient''' = ''-0.002,'' ''0.0,''\\ |
| 399 | [#ws_vertical_gradient_level ws_vertical_gradient_level] = ''0.0,'' ''1000.0,''\\\\ |
| 400 | That defines the subsidence/ascent profile to be linear up to z = 1000.0 m with a surface value of 0 m/s. For z > 1000.0 m up to the top boundary the gradient is 0.0 (m/s) / 100 m (it is assumed that the assigned height levels correspond with uv levels).\\\\ |
| 401 | With an appropriate construction of '''w_subs''' the height of the boundary layer ''z_i'' can be kept approximately constant.\\\\ |
| 402 | '''Attention:'''\\ |
| 403 | The large scale vertical motion is only applied to the prognostic equation for the scalar quantities (potential temperature, humidity if [#humidity humidity] = ''.T.'' or passive scalar if [#passive_scalar passive_scalar] = ''.T.'') because it cannot be applied to the momentum equations due to incompressibility. Thus, the model is not mass consistent. |