Skip to content

Commit

Permalink
Grid to earth relative is -1 * alpha for Cassini
Browse files Browse the repository at this point in the history
  • Loading branch information
@davegill @mgduda
davegill authored and mgduda committed Sep 25, 2018
1 parent c3c4660 commit 8632e1d
Showing 1 changed file with 6 additions and 11 deletions.
17 changes: 6 additions & 11 deletions metgrid/src/rotate_winds_module.F
View file
Original file line number Diff line number Diff line change
Expand Up @@ -161,7 +161,6 @@ subroutine metmap_xform(u, u_mask, v, v_mask, &
! Rotate U field
do j=us2,ue2
do i=us1,ue1
diff = idir * (xlon_u(i,j) - proj_stack(current_nest_number)%stdlon)
if (diff > 180.) then
diff = diff - 360.
Expand All @@ -172,8 +171,7 @@ subroutine metmap_xform(u, u_mask, v, v_mask, &
! Calculate the rotation angle, alpha, in radians
if (proj_stack(current_nest_number)%code == PROJ_LC) then
alpha = diff * proj_stack(current_nest_number)%cone * rad_per_deg * proj_stack(current_nest_number)%hemi
else if (proj_stack(current_nest_number)%code == PROJ_CASSINI) then
if ( idir == 1 ) then
else if ( (proj_stack(SOURCE_PROJ)%code == PROJ_CASSINI) .and. ( idir == 1 ) ) then
call latlon_to_ij ( proj_stack(SOURCE_PROJ) , &
xlat_u(i,j), xlon_u(i,j), x_u, y_u )
call ij_to_latlon ( proj_stack(SOURCE_PROJ) , &
Expand All @@ -187,10 +185,10 @@ subroutine metmap_xform(u, u_mask, v, v_mask, &
diff_lon = diff_lon + 360.
end if
diff_lat = xlat_u_p1-xlat_u_m1
alpha = atan2( (-cos(xlat_u(i,j)*rad_per_deg) * diff_lon*rad_per_deg), &
alpha =-atan2( (-cos(xlat_u(i,j)*rad_per_deg) * diff_lon*rad_per_deg), &
diff_lat*rad_per_deg &
)
else if ( idir == -1 ) then
else if ( (proj_stack(current_nest_number)%code == PROJ_CASSINI) .and. ( idir == -1 ) ) then
if (j == ue2) then
diff = xlon_u(i,j)-xlon_u(i,j-1)
if (diff > 180.) then
Expand Down Expand Up @@ -222,7 +220,6 @@ subroutine metmap_xform(u, u_mask, v, v_mask, &
(xlat_u(i,j+1)-xlat_u(i,j-1))*rad_per_deg &
)
end if
endif
else
alpha = diff * rad_per_deg * proj_stack(current_nest_number)%hemi
end if
Expand Down Expand Up @@ -281,8 +278,7 @@ subroutine metmap_xform(u, u_mask, v, v_mask, &
if (proj_stack(current_nest_number)%code == PROJ_LC) then
alpha = diff * proj_stack(current_nest_number)%cone * rad_per_deg * proj_stack(current_nest_number)%hemi
else if (proj_stack(current_nest_number)%code == PROJ_CASSINI) then
if ( idir == 1 ) then
else if ( (proj_stack(SOURCE_PROJ)%code == PROJ_CASSINI) .and. ( idir == 1 ) ) then
call latlon_to_ij ( proj_stack(SOURCE_PROJ) , &
xlat_v(i,j), xlon_v(i,j), x_v, y_v )
call ij_to_latlon ( proj_stack(SOURCE_PROJ) , &
Expand All @@ -296,10 +292,10 @@ subroutine metmap_xform(u, u_mask, v, v_mask, &
diff_lon = diff_lon + 360.
end if
diff_lat = xlat_v_p1-xlat_v_m1
alpha = atan2( (-cos(xlat_v(i,j)*rad_per_deg) * diff_lon*rad_per_deg), &
alpha =-atan2( (-cos(xlat_v(i,j)*rad_per_deg) * diff_lon*rad_per_deg), &
diff_lat*rad_per_deg &
)
else if ( idir == -1 ) then
else if ( (proj_stack(current_nest_number)%code == PROJ_CASSINI) .and. ( idir == -1 ) ) then
if (j == ve2) then
diff = xlon_v(i,j)-xlon_v(i,j-1)
if (diff > 180.) then
Expand Down Expand Up @@ -331,7 +327,6 @@ subroutine metmap_xform(u, u_mask, v, v_mask, &
(xlat_v(i,j+1)-xlat_v(i,j-1))*rad_per_deg &
)
end if
end if
else
alpha = diff * rad_per_deg * proj_stack(current_nest_number)%hemi
end if
Expand Down

0 comments on commit 8632e1d

Please sign in to comment.