Documentation for the WRF-STILT interface

A technical description of the WRF-STILT interface can be found in:

  Nehrkorn, T., J. Eluszkiewicz, S. C. Wofsy, J. C. Lin, C. Gerbig,
  M. Longo, and S. Freitas, 2010: Coupled weather research and
  forecasting - stochastic time-inverted lagrangian transport
  ({WRF-STILT}) model. Meteor. Atmos. Phys., 107 (1), 51-64,

1. Instructions for activating the WRFV3 "avgflx" package:

Starting with version 3.2 of WRF, two steps are needed to activate the output of time-averaged winds (and convective mass fluxes, if using the Grell-Devenyi cumulus scheme) needed for the WRF-STILT interface:

1.1. Add two lines to the namelist file, to the "&dynamics" namelist:

 do_avgflx_em                        = 1, 1, 1, 1, 1, 1, 1, 1, 1,
 do_avgflx_cugd                      = 1, 1, 1, 1, 1, 1, 1, 1, 1,

(This is a simple on/off switch, by domain, 1=on/0=off)

1.2. Activate "history output" for some additional variables in the Registry/Registry.EM file (Registry.EM_COMMON in v3.4).

This will require recompilation. The variables are:

muu, muv,mut, alt.

Also recommended: tke (this is not strictly necessary for the WRF-STILT interface, but potentially useful when using PBL schemes that compute TKE).

Sample lines shown below:

state    real   muu             ij     dyn_em      1          -     hr          "muu"
state    real   muv             ij     dyn_em      1          -     hr          "muv"
state    real   mut             ij     dyn_em      1          -     hr          "mut"
state    real   alt            ikj     dyn_em      1         -      rh        "alt"         "inverse density"               "m3 kg-1"

2. WRF-ARL converter

The software for the WRF-ARL converter is available from:

The latest software is in WRF-STILT-Release-3-5.tar.gz

The WRF-ARL converter is located in the "NWP/arl-format" subdirectory of this tar archive. Refer to the README file (included in the tar file) for documentation and installation instructions.

For earlier versions of WRF, some additional files are needed, and those available from older version of the WRF-STILT tarfile:

v3.2.1: WRF-STILT-Release-3-2-1.tar.gz

NOTE: There is a known bug in the avgflx implementation in WRFV3 that

      can lead to model crashes.  
      This tar file contains a fix for this bug for WRF version 3.2.1.

v2.2: WRF-STILT-Release-2-3.tar.gz

v2.1: WRF-STILT-Release-1-4.tar.gz

3. Financial Support

The Development of WRF-STILT at AER is supported by the National Science Foundation (NSF)