Every spring, the sun shines on the side of the stack of layers at the North Pole of Mars known as the north polar layered deposits. The warmth destabilizes the ice and blocks break loose.
![](https://scx1.b-cdn.net/csz/news/tmb/2019/imageavalanc.jpg)
Source:
https://phys.org/news/2019-09-image-avalanche-season-mars.html