The Liberty Ridge Area of Mount Rainier as viewed from the Carbon Glacier on May 31. (AP Photo/National Park Service) The ice is melting. (AP Photo of Mount Rainier/National Park Service)

I spend most of my life thinking about tomato blossom end-rot, the plague of subterranean grubs in my yard, my shortage of shoelaces, the profusion of ominous warning lights on the dashboard of the Honda, etc. But I usually devote at least a few minutes a day to pondering the end of the world as we know it.

You don’t want to obsess over that stuff, of course. Eschatology in moderation, I always say.

The last few days I’ve been thinking of icy-crusted water worlds without atmospheres in which submarine sentient creatures  develop the means to exploit hydrocarbons for energy.

We know the universe is chockablock with planets, and many of them are likely to be like Europa, frozen on the outside, rather than like Earth, with waves lapping on palm-tree-studded shores. Astrobiological orthodoxy holds that you need a terrestrial body, with land, to develop technology, though I can’t quite remember why that is, and will therefore discard it for the sake of my thought experiment. Also it stands to reason that a cold, dark, watery biosphere, such as would be seen within a Europa, is unlikely to produce complex, energy-intensive, neurobiologically robust life forms, such as fish, much less big-headed engineers. But let’s also ignore that on the grounds that once again it is inconvenient for my narrative. In my imaginary planet there is a civilization! Creatures swimming, singing, dancing, scooting around in submarines, building cities, holding big sporting events, partying in each other’s hot tubs (which are actually pockets of hot air). The neo-Europans have all kinds of new, nifty technologies, but they also have a conundrum.

The ice is melting.

Right? You see where I’m going. There are scientists who declare that the interior sea is getting hotter and melting the icy crust! And they say this is bad. They say this cannot continue. The neo-Europans must change their ways!

But it’s too hard. So some folks say, no, wait, your science is all wrong. We’re not actually warming our sea, and the ice isn’t melting, and even if the ice is melting (pivoting in their science-doubting) it’ll all be fine, and someday we’ll be able to, you know, swim to the surface and stare at the stars and become surfers, etc.

I worry about those icy worlds. And about the Earth-like, rocky worlds, too. And about this one, by the way.

My guess — lacking any data — is that intelligent, technological life is very rare in the universe but that the number of planets (or habitats) with engineers and scientists is still more than one. You can do the Drake Equation yourself and come up with whatever result you want, since it’s mostly guesswork. I’m in the “functionally alone” camp, which doesn’t mean there’s no one else out there — just that we’re all scattered across a very large space. But here’s the point I’m slowly dog-paddling toward: Any intelligent, technological species will need to understand its habitat quickly and make adjustments in behavior lest the unintended consequences of technology render that world uninhabitable.

I believe the climate-change debate, or something like it, is happening all over the universe — that it’s a phase every planet has to go through.

Here on Earth this discussion should go beyond climate change, since there are other possible problems that could someday become urgent and disruptive on a global scale — say, the continued deterioration of the human microbiome due to overuse of antibiotics, or a global nuclear conflagration, or a terrorism event involving an exotic pathogen.

And then there’s the Matrix. Stephen Hawking and three other big-name scientists recently published a scary column about the potential promises and perils of artificial intelligence, calling it “potentially the best or worst thing to happen to humanity in history”:

One can imagine such technology outsmarting financial markets, out-inventing human researchers, out-manipulating human leaders, and developing weapons we cannot even understand. Whereas the short-term impact of AI depends on who controls it, the long-term impact depends on whether it can be controlled at all.

In the meantime, can they invent an iPhone with a battery that doesn’t die by lunchtime?

All these things emerge, you may notice, from science and engineering. The Drake Equation ends with the rather ominous L, representing the average longevity of technological civilizations. Your guess is as good as mine. I try to be optimistic, though am nagged, as always, by Copernican Principle doubts.

On Monday, David Ropeik posted an article at (originally published at Slate) titled “Godzilla and the Birth of Modern Environmentalism.” He writes about the Castle Bravo nuclear test that inspired the Japanese movie monster:

Castle Bravo played a key role in establishing the deep fear of all things nuclear that persists to this day, helped give rise to modern environmentalism, and even planted the seeds of a basic conflict modern society is struggling with: Are the benefits of modern technology outweighed by the threats they pose to nature itself?…

Of course, humans are a species too, not separate from but a part of the natural world, and like all species our interactions with the natural world have all sorts of impacts. True, the human intelligence that allowed us to master fire has meant that we have done far more harm than other species. But technology is double-edged blade. Science and technology have also brought fantastic progress and offer great hope, including solutions for the mess technology helped us make in the first place….

We now live in an engineered world, and nothing is going to change that. The ship has sailed.

Inhabitants of engineered worlds have to learn how those worlds work and to adjust their behavior to accommodate physical realities and constraints. You can’t pretend that everything is going to operate smoothly until the end of time. We need to do the calculations correctly and double-check our math.

Ladies and gentlemen, sharpen your pencils.

[Update: This idea, of a managed, engineered planet, is something I’ve been following for a few years now — see, for example, my “Spaceship Earth” story of early 2012. Here are some further resources if you want to follow up:

David Grinspoon discussed the idea of “Terra Sapiens” in his Sagan Lecture at AGU this year. Here’s the YouTube clip of his speech. I also discussed the speech at the end of my recent Smithsonian story on Carl Sagan.

Mark Lynas tackled the idea of a managed planet in his book The God Species. So too did Stewart Brand in his book Whole Earth Discipline.

A different and less technophilic take comes from Bill McKibben in his book Eaarth: Making a Life on a Tough New Planet.]