(Credit: kazuend/Unsplash) Catastrophic climate change seems inevitable. Between the still-accelerating pace of greenhouse gas emissions and the voices of global warming deniers, hitting the targets laid out in the Paris Accord to slow the pace of a warming climate feels increasingly elusive. To hit even the 2 degree Celsius cap on a global temperature increase, emissions would need to peak in 2020, or less than three years from now, and keep going down after that. We could do it, but will we? If we can't change our behavior, perhaps there's another way to control our climatic destiny. One that's received a lot of attention recently is geoengineering, or somehow deploying technology to compensate for the effects of carbon dioxide and other greenhouse gases and bend the climate to our will. Climate scientists as far back as the 1960s have been proposing ways to counteract the effects of greenhouse gases in our atmosphere to mitigate the consequences of climate change. Some are fairly ludicrous, others are quite feasible. But letting these planet-wide fixes loose on the world could wreak more havoc than they prevent, scientists worry. And the nightmare scenarios range anywhere from large-scale famine to international warfare. The tension at the heart of the debate is that we may not have a choice. Warming may reach a point where even potentially dangerous solutions seem feasible, and if that time comes, well, perhaps we should have some options handy.