It's a topographical map, which traditionally use colour to represent elevation, darker colours usually being higher and lighter colours being lower.

Anyone who has, and can run, a fusion reactor (Or some super-powerful laser array) is more than capable of making their own nuclear bombs more easily by another method.

>I'm going to have some very angry-looking men carrying automatic weapons showing up at my front door very quickly.

You can buy it online in the US, though not in particularly large amounts. Buy a company with a legitimate use for it, order it in bulk and voila, you have Uranium 238.

Better and more effective to focus on commercial transport, manufacturing processes and other various industrial waste and pollution. A carbon tax would do considerably more good for the environment than switching everyone to electric cars tomorrow.