Geological change usually takes thousands of years to happen but we are seeing the climate changing not just in our lifetimes but also year by year.

NASA will send up a big sun shade that will be in orbit between the earth and sun and deflect 2 or 3 percent of the sunshine back into space. It would be cheaper than the international space station.

For each of our actions there are only consequences.

China will soon emit more greenhouse gases than America, but its regime knows if it caps aspirations there will be a revolution.

If we gave up eating beef we would have roughly 20 to 30 times more land for food than we have now.

One pound of uranium is worth about 3 million pounds worth of coal or oil.

Just after World War II, this country led the world in science by every way you could measure it, yet the number of scientists was a tiny proportion of what it is now.