GMT is a historic term which is today obsolete. UTC is a time defined not by the movement of the earth, but by a collection of atomic clocks all over the world. When UTC and UT1 drift apart for more than 0.9 s, a leap second is inserted into UTC to correct this. UT2 is an even better corrected version of UT0 which is used in astronomy. GMT is a term that was used before time was defined internationally by an atomic time reference in the late 1950s.
Most weather satellites are in geosynchronous orbit.
The higher the latitude, the worse the view from a geosynchronous satellite. To get useful pictures at the higher latitudes, you need a polar orbiting satellite. Because the strips are photographed at different times, the result isn't a true image, but a composition. We don't currently use polar satellite data routinely, so we don't have the data to post. The satellite images shown here is generated from large data sets which are archived on a private server.