COSP 2 differs from COSP 1 in requiring users to map grid-scale inputs to
subgrid-scale inputs, if required, and to convert cloud physical properties
to the optical properties required by each simulator. The paper describing
COSP 2, http://doi.org/10.5194/10.5194/gmd-11-77-2018, has further details.

This directory includes routines to perform both steps consistent with COSP 1.
The routines take as input a fixed description of clouds and precipitation.

Subcolumn samples are generated using the SCOPS routines and random number
generator originally developed for the ISSCP simulator, including three
possible specifications for cloud overlap. These routines are in subcol/.

Routines mapping cloud and precipitation to optical properties are in optics/.
These routines are the same as are used in COSP 1.

Users are encouraged to use information already available from the host model
and/or to develop their own versions of these routines consistent with host
model assumptions so that output from COSP is more consistent with the cloud
and radiation properties affecting the model's solution. 
