This is a local dust storm on Mars located near the edge of the south polar cap.
Click on image for full size
Image from: Calvin J. Hamilton, LPI, and NASA
Martian Global Dust Storms
This image shows a local dust storm near the edge of the south polar cap. Viewing of this image at high resolution is recommended. This fascinating image shows dust swirling over a large area.
Martian global dust storms tend to start in the southern hemisphere with a local dust storm, such as the one shown here. Southern spring and summer seem to be the season for global dust storms. Local dust storms seem to be swept into huge storms which envelope the entire planet, as was discovered by the Viking mission to Mars in the 1970's. Global dust storms do not seem to occur every Martian spring or summer, however.
The action of sands carried by winds during Martian global dust storms makes a great contribution toward wearing down rocks on the Martian surface.
You might also be interested in:

Dried debris left after a flood is "wind mobile" and can be lifted into the air by winds. The general process by which this occurs is called "saltation". Saltation is the primary form of abrasion and erosion
...more
There are two main weathering agents on Mars: wind and acid fog. Although acid fog can be very important, because large amounts of water are not readily accessible from the Martian surface, the action
...more
The surface pressure of Mars is about 1/150th that of the surface pressure of the Earth. This means that there are much fewer molecules in the atmosphere. This means that the atmosphere near the surface
...more
During the Mars Pathfinder Rover's exploration of the Martian surface, it traversed what scientists now call the "Mermaid Dune", covered with soils. The soil on top of Mermaid Dune seemed to have a dark
...more
Soils found by the Rover do not seem to be derived from the rocks at the Pathfinder landing site. They do not seem to be the weathering products of the eroded rock nearby. Scientists did not find evidence
...more
This is the first image showing clouds of Mars taken from the lander. Ground based viewing of Mars has shown that clouds seem to be plentiful only in the middle latitudes This may be because water of Mars
...more
Prior to the Mariner missions, we had to rely on ground-based observations to look at Mars. Using ground-based observations, scientists were able to identify channels, polar caps which varied with season,
...more
The Mars Exploration Rovers are six-wheeled robotic vehicles that are exploring the surface of Mars. The rovers, powered by solar panels, are robotic "field geologists" that are examining Martian rocks
...more