It turns out that Mars, with no help from CO2 or the Koch Brothers, has experienced massive climate change. The findings, based on Mars Reconnaissance Orbiter radar data, help make the point that significant drivers of climate change have nothing to do with mankind’s puny influence. Scott K. Johnson reports at ArsTechnica:

Layers in the Antarctic and Greenland ice sheets record ice age histories on Earth, and the ice caps of Mars’ would tell us a great deal—except we can't really go drill cores from the darn things. (snip) Working with images around the edges of the Martian ice caps, researchers have been able to catch glimpses of such layering. But without understanding how those glimpses connect together, the information they can reveal is limited.

A team of scientists led by Isaac Smith and Nathaniel Putzig of the Planetary Research Institute used radar data from the Mars Reconnaissance Orbiter to stitch together an X-ray-like look at the layering within the polar ice.

Most of the action was found at the northern pole, where the ice is up to 2km thick. The researchers were able to pick out layers of accumulation as well as several major breaks marking periods of disappearing ice. Since the last break about 370,000 years ago, ice has been moving back to the poles—meaning Mars is currently in an “interglacial” period.

The layer of new accumulation at the northern pole was as much as 320 meters thick. That number is much higher than early images had hinted at, but it is close to predictions made using models. This layer is thinner and a bit more complicated at the southern pole, equaling about eight percent of the volume of the northern layer. In total, there is about 87,000 cubic kilometers of newly accumulated ice—enough to cover the surface of Mars with about 60cm of it.

Mars's northern ice cap. Credit: ESA/DLR/FU-Berlin

The source of Mars’s climate change: orbital shifts.

Mars has orbital patterns that affect its climate, too. In fact, Mars’ orbital cycles swing to greater extremes than Earth’s. For example, Mars’ current axial tilt is about 25°, but it has varied within a range of 18° to 48° over the past 10 million years. Those orbital changes have influenced its climate….

So Mars has more powerful orbital cycles than earth, meaning its climate shifts are more dramatic, too.

Now if only there were a way for government bureaucrats to grab power and enrich crony capitalists trying to alter the earth’s orbital cycle, Al Gore could launch a new chapter in his career of scare-mongering.

Hat tip: Byron Hood