Abstract We analyzed six Kelvin‐Helmholtz (K‐H) vortex events from Mars Atmosphere and Volatile EvolutioN (MAVEN) measurements. We found that fully developed vortices can occur at Mars’ equatorial flanks and in the southern hemisphere, while they were previously observed only in the northern hemisphere. This implies that they do not exhibit a hemispheric asymmetry, and may occur globally as long as onset conditions are satisfied. We also estimated growth rates of 10−3 $1{0}^{-3}$–10−2 $1{0}^{-2}$ s−1 ${\mathrm{s}}^{-1}$, and found that the inclusion of heavy planetary ions reduces growth rates while increasing the directions over which K‐H instability occurs. We calculated instantaneous ion loss rates due to detachment of K‐H vortices of 1025 $1{0}^{25}$–1027 $1{0}^{27}$ s−1 ${\mathrm{s}}^{-1}$, rivaling other loss mechanisms in contributing to Mars’ global atmospheric escape. The inferred higher occurrence rate of K‐H instability at Mars over a larger spatial domain strongly suggests a more significant contribution to overall atmospheric loss than previously thought.

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