dd20 = one
IF( (facz.GE.dd).AND.(facz.LT.dd20) ) THEN
plumek(i) = one - min(one,(facz-dd)/(dd20-dd))
dd20 = (abs(SPDepth(i)))
tempN20 = dd20*tempN20
plumek(i) = one - min(one,two/dd20*facz-tempN/tempN20)
& three/dd20*facz - three/(dd20*dd20)*facz*facz
_RL facz, dd, dd20
dd = dd20/SPovershoot