diff --git a/src/problem.F90 b/src/problem.F90
index ceb2987..3d55479 100644
--- a/src/problem.F90
+++ b/src/problem.F90
@@ -781,7 +781,7 @@ module problem
 
 ! angular speed and triginometric functions
 !
-      om     = dpi / tsat
+      om     = dpi / tsat / (1.0d0 - esat)
       sn     = 0.0d0
       cs     = 1.0d0