Changes between Version 40 and Version 41 of OMI_observation_modules

Timestamp:

Mar 8, 2024, 10:58:27 AM (7 weeks ago)

Author:

lnerger

Comment:

--

OMI_observation_modules

@@ -155 +155 @@
  - Specify the localization variables (These variables are usually set in `init_pdaf` and included with `use mod_assimilation`)
    - `locweight`: Type of localization (see table below)
-   - `cradius`: The localization radius (cut-off radius for the observations, weight is always =0 for distances > cradius)
-   - `sradius`: The support radius of the localization weight function
+   - `cradius`: The localization radius or directional radii (cut-off radius for the observations, weight is always =0 for distances > cradius)
+   - `sradius`: The support radius (or directional redii) of the localization weight function
 
 The setting of `locweight` influences the weight function for the localization. The choices are standardized as follows
@@ -168 +168 @@
 Here, 'regulation' refers to the regulated localization introduced in Nerger, L., Janjić, T., Schröter, J., Hiller, W. (2012). A regulated localization scheme for ensemble-based Kalman filters. Quarterly Journal of the Royal Meteorological Society, 138, 802-812. ​[https://doi.org/10.1002/qj.945 doi:10.1002/qj.945].
 
-Note:
-- The localization in OMI is isotropic. Thus, it uses the same `cradius` in all directions. If different localization scales should be applied e.g. in the vertical compared to the horizonal one needs to scale the vertical coordinates. 
+**Notes:**
+- **isotropic localization**: If `cradius` and `sradius` are scalar values, the localization is isotropic. Thus, it uses the same `cradius` in all directions. If different localization scales should be applied e.g. in the vertical compared to the horizonal one needs to scale the vertical coordinates. 
+- **non-isotropic localization**: Nonisotropic localization was introduced with PDAF V2.2: `cradius` and `sradius` can declared as vectors of length `thisobs%ncoords` and each element can get a different value. In this case, the values defined a non-isotropic localization according to the values specified in `cradius` and `sradius`.
 
 == `localize_covar_OBSTYPE` ==
@@ -189 +190 @@
    - `cradius`: The localization radius (cut-off radius for the observations, weight is always =0 for distances > cradius)
    - `sradius`: The support radius of the localization weight function
+
+**Notes:**
+- **isotropic localization**: If `cradius` and `sradius` are scalar values, the localization is isotropic. Thus, it uses the same `cradius` in all directions. If different localization scales should be applied e.g. in the vertical compared to the horizonal one needs to scale the vertical coordinates. 
+- **non-isotropic localization**: Nonisotropic localization was introduced with PDAF V2.2: `cradius` and `sradius` can declared as vectors of length `thisobs%ncoords` and each element can get a different value. In this case, the values defined a non-isotropic localization according to the values specified in `cradius` and `sradius`.
+
 
 == Additional routines for 3D-Var ==