Evidence of Global Warming on Mars

In the light of new research, scientists have shown that dusty tornadoes called dust devils and gusty winds have helped the surface of Mars become darker, allowing it to absorb more of the sun's rays.

The research comes from US planetary scientists, who suggest the Red Planet warmed by about 0.65C from the 1970s to the 1990s, similar to Earth's 0.6C average temperature rise during the 20th Century.

"It could be coincidental or it might be the needle in the haystack," said climatologist William Kininmonth, former head of the National Climate Centre in Melbourne. "It's an interesting observation, as it's the same time period as Earth's temperature has been warming."

While some scientists, like Kininmonth, argue that there was enough natural climate variability to account for global warming on Earth, others do not agree, saying that it hasn't got anything to do with the question of human impact on global warming on Earth, and that it's not an excuse to argue that humans are not causing global warming on Earth.

Lori Fenton at the NASA Ames Research Center in Moffett Field, California, and colleagues used a computer model to study the effect that winds have had on Mars' climate, based on those devised to study global warming on Earth, adding Martian features such as a cold, airless surface and a shifting south polar ice cap while subtracting Earth's oceans and atmosphere.

During the 1970s, Mars experienced several large wind storms that stirred up bright, shiny dust particles and redistributed them around the planet, and in the 1980s and 1990s, smaller-scale processes like dust devils tidied up the planet, pushing the bright dust aside to expose the darker rocks below.

This process has decreased the planet's albedo, its ability to reflect solar radiation, and that, according to some of the scientists, had a bigger influence on climate than greenhouse gases such as carbon dioxide.

The study also predicted that Mars will continue to warm, due in part to a cycle caused by the planet's darkening surface.

"The darkened surfaces warm up, heating up the air just above the surface. This encourages formation of dust devils, which sweep up dust and [further] darken the surface," Fenton explained.

However, there are also other researches that sustain that although albedo had something to do with the recent climate changes, it can only have a local effect and cannot explain the observed warming record.

As debates on the topic remain open, we should not blame only external factors for the recent climate changes on Earth and pretend that over a century of pollution had nothing do to with it...