real function dpol(mygrid,hisgrid) ! Compute spatial polartzation offset in degrees for the present ! time, between two specified grid locators. character*6 MyGrid,HisGrid real lat,lon,LST character cdate*8,ctime2*10,czone*5 integer it(8) data rad/57.2957795/ call date_and_time(cdate,ctime2,czone,it) nyear=it(1) month=it(2) nday=it(3) nh=it(5)-it(4)/60 nm=it(6) ns=it(7) uth=nh + nm/60.0 + ns/3600.0 call grid2deg(MyGrid,lon,lat) call MoonDop(nyear,month,nday,uth,-lon,lat,RAMoon,DecMoon, & LST,HA,AzMoon,ElMoon,vr,dist) xx=sin(lat/rad)*cos(ElMoon/rad) - cos(lat/rad)* & cos(AzMoon/rad)*sin(ElMoon/rad) yy=cos(lat/rad)*sin(AzMoon/rad) poloffset1=rad*atan2(yy,xx) call grid2deg(hisGrid,lon,lat) call MoonDop(nyear,month,nday,uth,-lon,lat,RAMoon,DecMoon, & LST,HA,AzMoon,ElMoon,vr,dist) xx=sin(lat/rad)*cos(ElMoon/rad) - cos(lat/rad)* & cos(AzMoon/rad)*sin(ElMoon/rad) yy=cos(lat/rad)*sin(AzMoon/rad) poloffset2=rad*atan2(yy,xx) dpol=mod(poloffset2-poloffset1+720.0,180.0) if(dpol.gt.90.0) dpol=dpol-180.0 return end function dpol