We report six years of observations of dayside temperatures of the
middle and upper atmosphere of Mars made by the Imaging Ultraviolet
Spectrograph instrument aboard the MAVEN spacecraft. Thermospheric
temperatures show strong long-term variability associated with Martian
season and solar cycle. Temperatures from both the Martian thermosphere
and mesosphere show strong short-term variability indicating coupling
from the lower atmosphere. The observed local time effect is strong in
both upper and middle atmosphere temperatures. The thermosphere tends to
be colder in the morning compared to the evening when temperatures are
higher. Middle atmospheric temperatures show cooling during the dawn and
dusk hours. Our analysis shows strong tidal activity during aphelion,
whereas non-migrating tides are suppressed during perihelion, possibly
due to increased dust activity. Observations during the deep minimum of
solar cycle 24 reveal that thermospheric temperatures are highly
variable with respect to local time if solar forcing, Mars-Sun distance,
and spatial effects are removed. We will discuss these results in the
context of coupling between the lower and upper atmosphere of Mars.