_RL leith2fac, leith4fac
leith2fac =(viscC2leith /pi)**6
leith2fac =(viscC2leith /pi)**3
leith2fac=0. _d 0
& SQRT(leith2fac*grdVrt+leithD2fac*grdDiv)*L3
viscAh_Dlth(i,j)=(leith2fac*grdVrt+(leithD2fac*grdDiv))*L3
viscAh_ZLth(i,j)=(leith2fac*grdVrt+(leithD2fac*grdDiv))*L3