However, the cause of the albedo change was attributed to dust storms, not to a change in climate per se. Further, if there had been climactic change, there were only two datapoints to go on and a line drawn between them -- not exactly the kind of data that anyone on HN should choose to draw conclusions from.

More recent photographs suggest that there may be climactic cycles in effect, however the data gathered so far is utterly insufficient to even begin to guess at the systems and behaviors involved in that other planet.

One thing we do know is that Martian atmosphere is dramatically different from Earth's, and it doesn't make any more sense to draw conclusions about the one based on the other than it does to, say, conclude that Windows is subject to the same security vulnerabilities that Macs are.

In my mind, the question is not whether human activity affects climate, but how much. It seems absurdly naive to me to think that tens of billions of tons of CO2 combined with widespread deforestation will not have repercussions of any kind.