Earth may share one problem with its nearest planetary neighbour - global warming - according to a new study.

Scientists focused on Earth's climate of late have charted how greenhouse gases like carbon dioxide cause more heat to be trapped in our atmosphere. But Mars is heating up for an entirely different reason: dust storms.

Lori Fenton at the Carl Sagan Center led a study published in the recent issue of Nature. Comparing a map of Mars from 1976-1978 provided by the Viking's Infrared Thermal Mapper with a 1999-2000 map provided by the Mars Global Surveyor's Thermal Emission Spectrometer, the team noticed the Red Planet was changing colour.

Its dust covered surface used be a light red, but dust storms have revealed more of the dark red bedrock in the last couple of decades.

In a cycle that encourages further warming, the darker bedrock absorbs more heat from the Sun. This - in turn - causes stronger winds and more dust storms, revealing even more bedrock.

Looking back and forth between the two maps, Fenton estimates this cycle has caused Mars' temperature to rise 0.65 C over the past 20 years. This was calculated using a computer climate model similar to that used to project Earth's climate - minus the oceans, vegetation and clouds.

If the current conditions on Mars were projected 500 years into the future, it's possible the planet's ice caps could melt entirely. But other factors - such as a planet-wide dust storm that would evenly spread dust across the surface - could intervene.

When it comes back to our own planet, the explanation for global warming on Mars doesn't negate the warming of greenhouse gases on Earth's climate, the researchers note. (discoverychannel.ca)