LOGICAL useRBCuVel
& useRBCuVel,
IF ( tracerNum.EQ.-1 .AND. useRBCuVel ) THEN
IF ( useRBCuVel .AND. relaxUFile.NE.' ' ) THEN
IF ( (useRBCuVel .AND. relaxUFile.NE.' ') .OR.
IF ( useRBCuVel .OR. useRBCvVel ) THEN
IF ( useRBCuVel ) THEN
IF ( useRBCuVel .AND. relaxMaskUFile.NE. ' ' ) THEN
ELSEIF( useRBCuVel ) THEN
IF( useRBCuVel .OR. useRBCvVel ) THEN
useRBCuVel =.FALSE.
& 'cannot use RBC for U,V (useRBCuVel=',useRBCuVel,
IF ( useRBCuVel .AND. tauRelaxU.LE.0. ) THEN