A new study of the ice cap at Mars’ north pole was published in JGR: Planets, and it took a look at the ripple features using HiRISE images. They then created a model to simulate interactions between the ice and climate to see if they could generate those ripples. The model uses solar radiation values and the geometry of that radiation hitting one side of the ice cap but not the other, stretching out the ripples in one direction.

Once the model matched the images, the team found that the ripples were 10 meters across and one meter deep. Per the article in Eos: As the features age, the wavelength—the distance between each ripple—increases, and the ripples move toward the pole. This behavior held constant regardless of whether the researchers increased the atmospheric water vapor density or dialed it to zero, suggesting that the pattern forms regardless of whether the total amount of ice is increasing or decreasing.

This research gives us another piece of the climate change puzzle for Mars, and will hopefully lead to an understanding of when these changes happened. In this case, the wrinkles on the ice cap give an age of about 1000-10000 years. Not old at all, but we need more data.

More Information

Eos article

“Surface Roughness Evolution and Implications for the Age of the North Polar Residual Cap of Mars,” A. X. Wilcoski and P. O. Hayne, 2020 November 19, JGR Planets