The scientific excitement in comparing theory with data, and developing some understanding of global changes that are occurring, is what makes all the other stuff worth it.

If we drive our fellow species to extinction, we will leave a far more desolate planet for our descendants than the world we inherited from our elders.

Talking nice about sun and wind and green jobs is just greenwash.

The climate dice are now loaded. Some seasons still will be cooler than the long-term average, but the perceptive person should notice that the frequency of unusually warm extremes is increasing. It is the extremes that have the most impact on people and other life on the planet.

The five warmest years over the last century occurred in the last eight years.

The last time the world was three degrees warmer than today-which is what we expect later this century-sea levels were 25m higher. So that is what we can look forward to if we don't act soon.

Only in the last few years did the science crystallize, revealing the urgency - our planet really is in peril. If we do not change course soon, we will hand our children a situation that is out of their control.