Climate change is a foregone conclusion. The amount of carbon dioxide already in the atmosphere from two centuries-worth of fossil fuel burning (and, apparently, with decades more worth to come, given the glacial pace of efforts to slow said emissions) is enough to substantially warm global average temperatures. And that leaves so-called geoengineering—the deliberate, large-scale manipulation of planetary processes, in the words of the Royal Society—as the leading candidate for a techno-fix of the global warming problem, a fix the U.N. Intergovernmental Panel on Climate Change will begin to explore in Lima, Peru this week.

"The Arctic is melting much faster than people expected," noted physicist David Keith of the University of Calgary, during a talk outlining why "nature" should be preserved at the Perimeter Institute in Waterloo, Ontario, during the Equinox Summit in early June. "My generation utterly failed" to restrain greenhouse gas emissions, he remarked. "The next generation will have to do it."

Keith is one of the world's leading proponents of geoengineering research as well as an advisor on climate and energy to one of the world's leading philanthropists (and richest men), Bill Gates. As a maker of machines, including the first atomic-scale interferometer, Keith doesn't think we're running out of techno-fixes or even beginning to approach any limits on resources, technological progress or even the Earth's ability to support an expanding human population. "It is true that we will run out of easy oil in the Middle East with profound geopolitical impacts, but that's very different than running out of oil," he said. "We have an absurd amount of hydrocarbons in the world and a growing technological ability to get them out at prices we can afford."

In other words, peak oil (or coal or natural gas) won't save us from climate change. What might, according to Keith? Government regulations, which are what has allowed progress on remedying environmental problems from air pollution to eliminating toxic heavy metals from the soil.

So what then is the impetus for such regulations? A popular position, taken by both environmental groups and big business, is that nature offers economic value. So-called ecosystem services—such as clean water or pollination of crops—contribute billions to the global economy.

But if that's the only reason to save the natural world, Keith argues, then once someone like Keith builds a machine that can, say, deliver the same atmospheric benefits as the Amazon rainforest, there is no longer any compelling reason to save the "lungs of the Earth," as the Amazon is sometimes described. And that is exactly what geoengineering might lead to, "making the world safe for SUVs," in Keith's words.

Instead, Keith argued that there is a moral case to be made for saving nature, particularly as it serves, in his conception,  as a "psychological and moral" anchor for humanity, thanks to the biophilia identified by Harvard biologist E. O. Wilson. "If we can protect that anchor for a few percent of [global gross domestic product], we would be insane not to pass on to our grandkids the option to have that natural world," he said.

Of course, to do so means a heavier (human) hand on the formerly natural planetary systems, such as the cycling of CO2 from atmosphere to biosphere to lithosphere and back again. "This is about accelerating the end of nature," Keith said, and putting humans in charge of what were formerly natural events and processes, such as the weather. Many people might disagree that humans can ultimately achieve such control, but Keith may have a point when he paraphrased Harvard ecologist William Clark: "We need to decide whether to be sloppy gardeners or good gardeners, and whether we want a wild garden."