crumpled paper, switches, and the end of the world

[miriam_e]

I woke this morning trying to understand how crumpled paper works. Crumpled paper is really interesting stuff. When you are trying to gently crumple or uncrumple it, it makes those rustling sounds. It seems the complex 3d shape of the folds cause parts of the paper to snap into new positions suddenly. This is why you hear all those tiny click sounds -- they are switches. What I was trying to visualise this morning is how the folds make these switches. They must be really common and easy to make, because any time you crumple paper it creates lots of them. I'd love to understand their mechanics. Unfortunately I can't afford the time to investigate it. I have set myself a task to complete and I am far too easily distracted by these kinds of things.

Switches are marvellous things. Our computers are made almost entirely of billions of microscopic switches. Our brains consist of billions of tiny living animals (neurons) that interact as switches. There is some evidence now that our planet's climate may act as a switch, so that if we push it far enough it will flip into an entirely different mode, utterly hostile to human life. If that is the case we need to stop dithering around giving government subsidies of billions of dollars to the most polluting corporations and fix the climate. If it does get to the point where the climate switches then we can try to backpedal afterwards all we want and it won't make the slightest bit of difference. It will take far more work to switch it back than we could have access to... even with all our amazing technology. And what is the likelihood that we could do much at all if our life support systems were collapsing?

There have been a number of times before when the Earth's climate became extremely hostile to its dominant lifeforms. Some time ago I was reading about how incredibly efficient birds' breathing is. They are up to 200 times better at extracting oxygen from the air than mammals are. It was noted in the article that there have been several periods in the past where Earth's oxygen levels plummetted to very low levels bringing about major extinctions, and that this may be one of the reasons why birds are so good at getting oxygen out of air -- the ancestors of modern birds survived such an event. Our oxygen is manufactured by land plants and marine algae. We have been clearing the land of its vegetation since our ancestors first mutated into our current, giant-brained form, but luckily for us there have still been plenty of algae in the oceans. However if the Earth's climate does switch drastically into a new mode I wonder if that will continue to be true. I really don't want us to gamble on this.

Comments

[blackgrrr.livejournal.com]

but luckily for us there have still been plenty of algae in the oceans. However if the Earth's climate does switch drastically into a new mode I wonder if that will continue to be true.

From memory, if the oceanianic levels of acidity continue to rise, the algae starts to thrive sucking up all of the oxygen in the ocean. The fish start to die. As as more and more algae dies and falls to the bottom the sea begins to become anoxic. Which has additional feedback issues.

That's the theory, but they think it happened at least once before.

[miriam-e.livejournal.com]

Yep. Anoxia in seas and lakes is a major problem in many places around the world right now. They are colloquially called "dead zones" if I remember right. We create them. And they are occurring more often as our assault on the waters intensifies. I can't remember the details of the feedback loop involved, but overfishing and fertiliser run-off are major culprits in starting it. One of the worst is in the Black Sea I think, where about a third of that body of water is toxic to almost everything... and I think is increasing in area. I must re-read that article about it in Scientific American from a year or two ago.

What worries me more than dead zones though, is if sudden global warming or sudden cooling caused the major species of oxygen-producing algae to die off. Oxygen is an extremely active gas and would combine with other materials very quickly, so that we could have difficulty in breathing just years after such an event. We would have no chance to fix it. All our marvellous technology would come to nothing. In a single generation human life would disappear. We can move to higher ground or cooler or warmer latitudes; we can hoard food and water; we can fight off our neighbors. But how do we breathe if there is not enough oxygen?