Mars' massive dust storm in 2018 ended winter early

Scientists from the Royal Astronomical Society have released a new study investigating a gigantic dust storm that enveloped the entire planet of Mars in 2018. As the dust storm engulfed the entire planet, it destroyed a vortex of cold air around the planet's south pole, resulting in early spring in the hemisphere. While the dust storm destroyed the cold air vortex around the South Pole, it only resulted in minor distortions to the polar vortex in the northern hemisphere resulting in no dramatic seasonal changes.

During a two-week period beginning in June 2018, localized dust storms combined and spread to form a gigantic and impenetrable blanket of dust obscuring almost the entire surface of Mars. The massive dust storm coincided with the equinox on Mars and lasted until mid-September. This dust storm killed the NASA Opportunity rover by covering its solar panels with dust, leaving it unable to operate.

Researchers on the project examined the effects of the event on the atmosphere of Mars by combining data gathered from a Mars Global Climate Model that used observations from the ExoMars Trace Gas Orbiter and the NASA Mars Reconnaissance Orbiter missions. The massive dust storm gave scientists an opportunity to investigate how a global dust storm impacts the atmosphere at the poles of Mars.

The massive 2018 storm was the first global storm since 2007, and since 2007 multiple new missions and instruments were available in orbit around Mars, making the 2018 dust storm the most observed so far. Previous studies have shown that high levels of dust in the atmosphere of Mars could impact polar temperatures and winds significantly.

Researchers showed that high levels of dust from the storm had a profoundly different impact in each hemisphere. In the South Pole, the vortex was almost destroyed, and temperatures rose as winds fell dramatically. This team admits the vortex may have been starting to decay due to the onset of spring, but ultimately the dust storm was the main cause of an early winter. In the northern hemisphere, the vortex remained stable, and the onset of autumn followed its usual pattern.