--- MITgcm/pkg/seaice/SEAICE_OPTIONS.h	2002/11/12 20:47:27	1.2
+++ MITgcm/pkg/seaice/SEAICE_OPTIONS.h	2002/12/28 10:11:11	1.3
@@ -13,14 +13,29 @@
 
 #ifdef ALLOW_SEAICE
 
-C--    Write "text-plots" of certain fields in STDOUT for debugging.
+C--   Write "text-plots" of certain fields in STDOUT for debugging.
 #undef SEAICE_DEBUG
 
-C--    Allow sea-ice dynamic code.
-C      This option is provided to allow us to use the TAMC
-C      on the thermodynamics component of the code only.
-C      Sea-ice dynamics can also be turned off at runtime
-C      using variable SEAICEuseDYNAMICS.
+C--   Allow sea-ice dynamic code.
+C     This option is provided to allow use of TAMC
+C     on the thermodynamics component of the code only.
+C     Sea-ice dynamics can also be turned off at runtime
+C     using variable SEAICEuseDYNAMICS.
 #define SEAICE_ALLOW_DYNAMICS
 
+C--   By default, pkg/seaice defines forcing variable internally, in
+C     SEAICE_FFIELDS.h, and reads them in from files.  When CPP option
+C     SEAICE_EXTERNAL_FORCING is defined, the above forcing variables
+C     are defined and provided by an external package.  At present this
+C     option is hardwired for pkg/exf and the variables are passed using
+C     include file exf_fields.h.
+#undef SEAICE_EXTERNAL_FORCING
+
+C--   By default, the sea-ice package uses its own integrated bulk
+C     formulae to compute fluxes (fu, fv, EmPmR, Qnet, and Qsw) over
+C     open-ocean.  When this flag is set, these variables are computed
+C     in a separate external package, for example, pkg/exf, and then
+C     modified for sea-ice effects by pkg/seaice.
+#undef SEAICE_EXTERNAL_FLUXES
+
 #endif ALLOW_SEAICE