This artists concept illustrates a Martian dust storm, which might also crackle with electricity.
(NASA)
Every planet in our solar system is unique and hosts some peculiar weather conditions—scorching hot temperatures in Venus, massive cannibalistic storm in Jupiter, and fastest-blowing winds in Neptune, among others.
The poster planet for space exploration, Mars, witnesses the most extreme and powerful dust storms that engulf the entire red planet for weeks. And this has been one of the most intriguing and dangerous weather aspects that scientists have been trying to decipher. Being a prime destination to settle humans beyond Earth in the future, Martian weather is of immense research interest for space scientists.
Interestingly, a new study has shown that we can draw a baseline by comparing the similar weather patterns on the other planets to those on Earth. And one such feature is the annular mode.
Weather similarities between Mars and Earth
In June 2018 NASA’s Curiosity Rover used its Mast Camera, or Mastcam, to snap photos of the intensifying haziness the surface of Mars, caused by a massive dust storm. The rover is standing inside Gale Crater looking out to the crater rim. The photos span about a couple of weeks, starting with a shot of the area before the storm appeared.
(NASA)
Here on Earth, the annular mode depicts variabilities in the planet’s atmospheric flow that globally affects jet streams, precipitation and cloud formation. They are behind the regularities of storm systems like eddies and blizzards like those of New Zealand. However, the phenomenon is not associated with the cycle of seasons.
Dr J. Michael Battalio, who led this study, is a postdoctoral researcher in Earth and planetary sciences in Yale’s Faculty of Arts and Science. He has been conducting atmospheric observations of Mars for more than 15 years, and hence, found the presence of annular modes on the red planet.
As per the study, this weather feature is closely similar to the regularity of dust storms in the Southern Hemisphere of Mars. After finding this, the team of researchers at Yale University also looked for a similar phenomenon on Titan using the Titan Atmospheric Model (TAM).
Surprisingly, they discovered the annular modes in Titan as well. In fact, the simulation models highlighted more influential annular modes on Titan and Mars as compared to Earth. The study suggests that the phenomenon drives almost half of the wind variability on Mars, while two-thirds of the wind variability on Titan.
“Methane clouds and surface changes caused by methane rain on Titan have been observed before. And now it seems these events are connected to shifts of Titan’s strong jet stream, influenced by its annular modes,” explains co-author Juan Lora.
Helpful for future weather predictions
Representative Image
(Michael S. Helfenbein; Image courtesy of NASA/JPL-Caltech)
The findings are crucial in setting the groundwork for accurate weather forecast models to predict various weather events over Mars. Moreover, for the safety of future missions and before we think of sending humans to Mars, scientists would have to crack these forecasts to avoid weather extremes.
On this, Dr Battalio says: “I believe the first accurate forecasts of perhaps a few Mars days may be only a decade away. It is just a matter of combining better observational datasets with sufficiently refined numerical models. But until then, we can rely upon connections between the climate and weather to help anticipate dust storms.”
Dust storms are major extreme events on Mars and pose a considerable risk for future missions and settlement projects. The planet experiences all kinds of dust storms, from the smaller storms that last less than a day to some extreme ones that persist for days and even weeks.
Moreover, some global dust storms are powerful enough to sweep the entire planet—similar to the one that killed the Opportunity rover in 2019. Therefore, the weather models are vital in predicting the periodic extreme dust storms that occur on Mars.
“Understanding and predicting these events is vital for the safety of missions, particularly those that rely on solar power, but also for all missions as they land on the surface,” concludes Dr Battalio.
The results of this study have been published in the journal Nature Astronomy this week and can be accessed here.
