"I wonder whether the amount of greening over the lifetime of the clock is sufficient to cover the carbon generated by making it and shipping it from China."

I always wonder about that. But part of me also wonder why CO2 levels on Al Gore's pie chart come 400 years on average AFTER sea levels have already risen. And how CO2 (the "main point" most people try to use), is HEAVIER than O2 (oxygen). So with gravity, you would have to have a global hurricane so huge or major windstorm that would constantly mix the gases (kind of like spinning something with a spoon in the pot). And large cities like LA and Beijing release large amounts of the so called global warmers, but before even driving into a city like LA, you see a big dark brown hazy dome around it. That's all the so called global warmers...they don't even go up much past the skyscrapers.

I don't think today's scientists listen to the past like they should. I don't believe the Mayans were talking about a world ending, I think how our Earth rotates around the Sun, and it goes in an orbital pattern that causes the two to be closest during Summertime, the Mayans said that every 26,000 years the entire solar system orbits around the Milky Way. Who knows but I don't always go for some shady hypothesis that defies the laws of physics and gravity. Except when you get into string theory and quantum physics.

I try to keep an open mind but I still can't see how when our own solar system works in a way that divides its years into hot and cold, why shouldn't our solar systems orbit around the Milky Way not have some kind of effect?

Give me a reason to believe it, not something like "Well some scientists have said that..." I want to know how it's physically possible for CO2 to remain above O2 when the Earths radius is so massive. Ice melts and then eventually reforms. Everything in space usually forms and rotates in circles but they're often orbital that's why they're called orbits. Most stars have a partner star they orbit with...that's one thing that makes our Sun unique. So what I'm saying is that everything goes in cycles. Even our Solar System and Galaxy.

So instead of believing in scientists you site a civilization that have been extinct for a few hundred years? Very nice

Wow. I don't even know where to begin mocking noname