We know little of the consequences of the geoengineering process, such as spraying particles into the atmosphere that shade the planet from the sun's rays and could decrease its temperature. But this process is how dinosaurs disappeared from the Earth about 60 million years ago, by particles spewed by a volcano or a giant meteorite impact, and our species could follow suit.

Signs of a poorly understood but treatable house fire requires action, not inaction.

The first reaction to trauma is denial, then comes anger and finally, acceptance. I think the US is still between denial and anger, and I hope we will reach acceptance because almost perversely, right now, only the US has the technology that is needed for global economic change.

We are in the midst of the 6th largest extinction event in the history of the plant and the first caused by human action.

We know that the warming rising seas will swallow entire island nations that are about 25 percent of the UN vote and perhaps at the end, even our civilization. This realization is traumatic and the first reaction to trauma is denial. Since there is some remaining scientific uncertainty, a natural response is to deny that change is occurring. This is natural but it is very dangerous.

Technology is a many-headed monster and perhaps it would be better to regress to a safer past and avoid technological change; it is tempting to think like that.

As difficult as it is to eliminate the risk of nuclear warfare, it requires fewer changes to the global economy than does averting or reversing climate change.