  The evolution of eddy kinetic energy during the development of large regional
dust storms on Mars is investigated using the Mars Analysis Correction Data
Assimilation (MACDA) reanalysis product and the dust storm data derived from
Mars Global Surveyor Mars Daily Global Maps. Transient eddies in MACDA are
decomposed into different components according to their eddy periods: $P\leq1$
sol, $1<P\leq8$ sols, $8<P\leq60$ sols. This paper primarily focuses on the
Mars year 24 pre-solstice "A" storm that starts with many episodes of
frontal/flushing dust storms from the northern hemisphere and attains its
maximum global mean opacity after dust expansion in the southern hemisphere.
During the development of this storm, the dominant eddies in terms of eddy
kinetic energy progress from the $1<P\leq8$ sol eddies in the northern mid/high
latitudes to the $P\leq1$ sol eddies (dominated by thermal tides) in the
southern mid latitudes, and the $8<P\leq60$ sol eddies show a prominent peak
with the increased global-mean dust opacity. The peaks of the $1<P\leq8$ sol
eddies are found to best correlate with the average area of textured
frontal/flushing dust storms within 40$^\circ$N $-$ 60$^\circ$N. The region
where the $1<P\leq8$ sol eddies increase the most corresponds to the main
flushing channel. The eddy kinetic energy of the $P\leq1$ eddies, dominated by
$P$ = 1 and its harmonics, increases with the global mean dust opacity both
before and after the winter solstice in Mars year 24. The $8<P\leq60$ sol
eddies briefly spike during large, regional dust storms but remain weak if dust
storm sequences do not lead to a major dust storm. Zonal wavenumber analysis of
eddy kinetic energy shows that the peaks of the $1<P\leq8$ eddies often result
from combinations of zonal wavenumbers 1 to 3, while the $P\leq1$ eddies and
$8<P\leq60$ sol eddies are each dominated by zonal wavenumber 1.
