Geoscience Reference
In-Depth Information
Fig. 4.10
UAM model results compared with cross-track accelerometer measurements of the
CHAMP satellite for one overflight over the Northern Hemisphere in polar geomagnetic coor-
dinates at latitudes higher than 60
ı
. The dial shows 12 MLT on
top
, dusk side (18 MLT) to the
left
,
anddawn(06MLT)tothe
right
, respectively. Magnetic longitude coordinates are indicated with
the
black crosslines
.The
dotted line
follows along the orbital track from
13 MLT
with a
larger arrow
at the actual spacecraft position at 17:12:00 UT. The cross-track
fine black
arrows
correspond to the calculated UAM crosswind speed; the
colored arrows
show a cross-track
wind component as measured by CHAMP. The background wind vector pattern (
colored arrows
according to the scale on
top
) and the electric potential (
b/w color scale
) is calculated by the UAM
for this time moment
01 MLT to
direction (as shown by black arrows) compares quite well with the accelerometer
measurements of CHAMP (as shown by the collinear colored arrows). The observa-
tions show slightly more variations in form of mesoscale structures, but the general
shape and position of the dusk circulation cell and the wind amplitudes are well
reproduced.
