Browse Source

Updated documentation for cfrac

lon0
Bill Ladwig 7 years ago
parent
commit
aa683a54cd
  1. 29
      src/wrf/computation.py

29
src/wrf/computation.py

@ -973,33 +973,14 @@ def cloudfrac(vert, relh, vert_inc_w_height, low_thresh, mid_thresh, @@ -973,33 +973,14 @@ def cloudfrac(vert, relh, vert_inc_w_height, low_thresh, mid_thresh,
- return_val[0,...] will contain LOW level cloud fraction
- return_val[1,...] will contain MID level cloud fraction
- return_val[2,...] will contain HIGH level cloud fraction
For backwards compatibility, the default vertical coordinate type is
pressure, with default cloud levels defined as:
97000 Pa <= low_cloud < 80000 Pa
80000 Pa <= mid_cloud < 45000 Pa
45000 Pa <= high_cloud
If the vertical coordinate type is 'height_agl' or 'height_msl', the
default cloud levels are defined as:
300 m <= low_cloud < 2000 m
2000 m <= mid_cloud < 6000 m
6000 m <= high_cloud
Note that the default low cloud levels are chosen to
exclude clouds near the surface (fog). If you want fog included, set
*low_thresh* to ~99500 Pa if *vert_type* is set to 'pres', or 15 m if using
'height_msl' or 'height_agl'. Keep in mind that the lowest mass grid points
are slightly above the ground, and in order to find clouds, the
*low_thresh* needs to be set to values that are slightly greater than
(less than) the lowest height (pressure) values.
The *low_thresh*, *mid_thresh*, and *high_threshold* paramters specify the
low, mid, and high cloud levels in the same units as *vert*.
When using 'pres' or 'height_agl' for *vert_type*, there is a possibility
In mountainous regions, there is a possibility
that the lowest WRF level will be higher than the low_cloud or mid_cloud
threshold, particularly for mountainous regions. When this happens, a
fill value will be used in the output.
threshold. When this happens, a fill value will be used in the output at
that location.
This is the raw computational algorithm and does not extract any variables
from WRF output files. Use :meth:`wrf.getvar` to both extract and compute

Loading…
Cancel
Save