  We report on the interannual variability of the atmospheric ice/dust cycle in
the Martian polar regions for Mars Years 28-30. We used CRISM emission phase
function measurements to derive atmospheric dust optical depths and data from
the MARCI instrument to derive atmospheric water ice optical depths. We have
used autocorrelation and cross correlation functions in order to quantify the
degree to which dust and ice are correlated throughout both polar regions
during Mars Years 28-29. We find that in the south polar region, dust has the
tendency to "self clear", demonstrated by negative autocorrelation around the
central peak. This does not occur in the north polar region. In the south polar
region, dust and ice are temporally and spatially anti correlated. In the north
polar region, this relationship is reversed, however temporal correlation of
northern dust and ice clouds is weak - 6 times weaker than the anticorrelation
in the south polar region. Our latitudinal autocorrelation functions allow us
to put average spatial sizes of event cores and halos. Dust events in the south
are largest, affecting almost the entire pole, whereas dust storms are smaller
in the north. Ice clouds in north are similar in latitudinal extent to those in
the south (both have halos < 10{\deg}). Using cross-correlation functions of
water ice and dust, we find that dust events temporally lag ice events by 35-80
degrees of solar longitude in the north and south poles, which is likely due to
seasonality of dust and ice events.
