TITLE: 
WAVEWATCH III code upgrade

CHANGE REQUEST CLASS:
Major change

DESCRIPTION OF CHANGE:  
This is a major upgrade of the WAVEWATCH III code and hence it has its own
svn archive. In keeping with the standards developed during the EE project, 
major version changes of the model source code will have their own repository 
branch. This branch refers to WAVEWATCH III being upgraded from v 3 to v4. 
The initial upload of the code  refers to WAVEWATCH III v 4.05

  IMPORTANT NOTE !! : WAVEWATCH III version 4 is not backward compatible with
  WAVEWATCH III v 3. So input files that use WWW-III v 3 will not work with 
  WW-III v 4. 

  Specific changes that have gone into v4 are as follows:

  * WAVEWATCH III now works with curvilinear and irregular grids (though this 
    feature is not used at the current implementation stage). This is a major
    issue as it removes an earlier limitation of regular grids. 

  * WAVEWATCH III now has a new physics package (referred internally in the 
    code as ST4). This package accounts for 
    * a new wave growth term that is a modification of an existing term
    * a new term for dissipation of propagating swells, and 
    * a new term for wave dissipation 
    Details of this physics package are outilined in the manual, and it is the
    basis for the current implementation being done using wave_multi_1.v3.0.0

  * The number of available output parameters has gone from 31 to 53. (Though
    none of the additional new parameters are going to be output in operations
    currently).   

BENEFIT OF CHANGE: 
The biggest advantage of the new version of WAVEWATCH III is the new physics 
package that is being implemented. This physics package has shown a significant 
improvement in skill in retrospective tests. Specifically, the over estimation 
of swell heights in the Nrothern Hemisphere and the overestimation of heights
in the Southern Hemisphere are both addressed. There is also a reduction of the
random error with the new source term. 

USER IMPACT STATEMENT:
Since we are implementing a new physics package the users will have to a 
detailed assesment of the forecasts and update any corrective procedures
they use.

TECHNICAL IMPACT STATEMENT:
This package is being implemented in parallel with the wave_multi_1.v3.0.0. 
Since WW-III v4 is not compatible with earlier versions of WW-III, older 
input files will not work. NCO thus has to make sure that this code is not
linked with earlier versions of wave_multi_1 

RISKS:
The major risk is in trying to implement wave_code.v4 with earlier versions of
wave_multi_1 (before v 3.0.0). All input files for v 3.0.0 have been tested. The modeling system has been retrospectively tested for two yers of hindcasts in
global and Great Lakes domains without problems.  

PROPOSED IMPLEMENTATION
DATE: 
TIME: