:orphan:

.. ****************************************************************************
.. CUI
..
.. The Advanced Framework for Simulation, Integration, and Modeling (AFSIM)
..
.. The use, dissemination or disclosure of data in this file is subject to
.. limitation or restriction. See accompanying README and LICENSE for details.
.. ****************************************************************************

global_environment
------------------

.. command:: global_environment ... end_global_environment
   :block:

   .. parsed-literal::

    global_environment
       land_cover_ ...
       land_formation_ ...
       sea_state_ ...
       wind_speed_ ...
       wind_direction_ ...

       wind_table_
          <altitude-value> <wind-direction-value> <wind-speed_value>
          ...   // wind_table data sets in order of increasing altitudes.
          ...
       end_wind_table

       cloud_altitude_limits_ ...
       cloud_water_density_ ...

       rain_altitude_limit_ ...
       rain_rate_ ...

       central_body_
         polar_offset_angles_
       end_central_body

    end_global_environment

Overview
========

The global_environment block defines the attributes of the global environment.  Various objects make use of data
defined in this block.

Commands
========

.. command:: land_cover <land-cover-type>

   Specify the land cover for the :command:`_.receiver` clutter model.  Valid values are:

   * ::general
   * ::urban
   * ::agricultural
   * ::rangeland_herbaceous
   * ::rangeland_shrub
   * ::forest_deciduous
   * ::forest_coniferous
   * ::forest_mixed
   * ::forest_clear_cut
   * ::forest_block_cut
   * ::wetland_forested
   * ::wetland_non_forested
   * ::desert

   Default general

.. command:: land_formation <land-formation-type>

   Specify the land formation for the :command:`_.receiver` clutter model.  Valid values are:

   * ::level
   * ::inclined
   * ::undulating
   * ::rolling
   * ::hummocky
   * ::ridged
   * ::moderately_steep
   * ::steep
   * ::broken

   **Default** level

.. command:: sea_state <value>

   Specify the sea state for the :command:`_.receiver` clutter model.  Valid values are 0 - 6.

   ======  ===========  ==============
   Degree  Height (m)   Description
   ======  ===========  ==============
   0       no wave      Calm (Glassy)
   1       0 - 0.10     Calm (Rippled)
   2       0.10 - 0.50  Smooth
   3       0.50 - 1.25  Slight
   4       1.25 - 2.50  Moderate
   5       2.50 - 4.00  Rough
   6       4.00 - 6.00  Very Rough
   ======  ===========  ==============

   **Default** 0

.. command:: wind_speed <speed-value>

   Specify the wind speed.

   **Default** 0 m/s

.. command:: wind_direction <angle-value>

   Specify the wind direction.

   **Default** 0 deg

   .. note::
      WSF wind direction is the direction to which the wind flows; not from where it comes.

.. command:: wind_table   ...  end_wind_table

   Specify wind-value-data sets using 3 parameters per entry (from lowest altitude to highest):
   :altitude <length-value> wind direction <angle-value> wind speed <speed-value>.

::

           wind_table
                  0 ft    90 deg   20 kts
               5000 ft    95 deg   25 kts
              10000 ft   100 deg   30 kts
              15000 ft   100 deg   35 kts
              20000 ft   120 deg   40 kts
              25000 ft   125 deg   45 kts
              30000 ft   125 deg   50 kts
              35000 ft   130 deg   55 kts
              40000 ft   130 deg   60 kts
           end_wind_table

   **Default** If no wind_table, then WSF defaults to values assigned to wind_speed_ and wind_direction_.

   .. note::
      WSF wind direction is the direction to which the wind flows; not from where it comes.

   .. note::
      Insert altitudes in order from lowest to highest.

.. command:: cloud_altitude_limits <length-value> <length-value>

   Specify the minimum and maximum altitude extent in which clouds are defined to occur. This is used by some
   :command:`attenuation models <attenuation_model>`.

   **Default** 0 m 0 m (no clouds)

.. command:: cloud_water_density <mass-density-value>

   Specify the density of water within the cloud. This is used by some :command:`attenuation models <attenuation_model>`.

   **Default** 0 kg/m^3

.. command:: rain_altitude_limit <length-value>

   Specify the altitude below which rain is present. This is used by some :command:`attenuation models <attenuation_model>`.

   **Default** 0 m

.. command:: rain_rate <speed-value>

   Specify the rainfall accumulation rate. This is used by some :command:`attenuation models <attenuation_model>`.

   **Default** 0 m/s

.. include:: central_body_commands.txt

.. block:: global_environment

.. command:: polar_offset_angles <angle-value> <angle-value>

   Specify the central_body_'s polar offset angles (:math:`x_p` and :math:`y_p`, respectively) of the Celestial Intermediate Pole (CIP) with respect to the WCS (ITRS) coordinate system.  Providing these values (of the order of tenths of arc-seconds) enables very highly accurate conversions between ECI and WCS coordinates.

   **Default** 0.0 rad 0.0 rad