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When Microbes Ate the Ocean
museumpeace writes "When /. discussed a story about microbes that could break down water as a hydrogen source, many commentors went off on a tangent joking about runaway germs eating the oceans. Now, prof Joe Kirschvink and students at CalTech propose that indeed, the worst iceage ever, which nearly ended life on earth 2.3 billion years ago, was the result of algae evolving the ability to break down water and flooding the atmosphere with oxygen. The absence of oxygen consuming organisms at that time is said to have lead to destruction of atmospheric methane which had hitherto warmed the earth. The professor concludes: 'We haven't had a Snowball in the past 630 million years, and because the sun is warmer now it may be harder to get into the right condition. But if it ever happens, all life on Earth would likely be destroyed.'"
While this sounds pretty bad, it seems that this was nature's way of "terraforming" our planet. It seems these bacteria might be handy for naturally creating other worlds we can inhabit. After all, we already have organisms that breathe oxygen.
Yes, See SLIMES (subsurface lithoautrophic microbial ecosystems) that exist deep in the earth *completely* disconnected from surface activity. They get heat from the earth's core and food from breaking down rocks; these would probably survive and in time could recolonize the surface.
See: Wilson, E.O. The Future of Life, 2002
Determing the cause of a global freeze which we think happened 2.3 billion years ago has got to be pretty tough. Their actual article is not linked, so does anyone have a link or an idea about how they determined this?
Definitely must be Vonnegut's Cat's Cradle!
God: When you do things right, people won't be sure you've done anything at all.
As I understand it, you are saying we will destroy ourselves by changing the ecosystem and allowing previously insignificant but dangerous organisms to become significant and kill us off (normally I would have glossed over your poetic post, but it was modded as insightful so I read it more carefully).
e vent). IMO this is probably true, but not as bad as it sounds. Many of the species that are dying off are not important to the big scheme of things, and the complicated interweb of life will compensate. The mass extinction is sad, but probably won't be the end of humans.
I don't really get how that will happen. Yes, I agree that we treat this planet pretty badly, but I think the planet and humans are tough enough to take it.
You may have a point, though. Many scientists postulate that humans are currently creating a mass extinction, similar to what killed off the dinosaurs (see http://en.wikipedia.org/wiki/Holocene_extinction_
The article points out that if Earth was a bit farther away from the Sun, then the Carbon Dioxide would have frozen out of the atmosphere, thus preventing that particular greenhouse gas from bringing on a subsequent warming period. Mars has almost exactly that situation. One or the other of the poles is always cold enough to freeze Carbon Dioxide out of its atmosphere. Too little greenhouse gas ==>>planet stays too cold==>> water permenantly locked up as ice.
With the discoveries of the last couple of years we know Mars has lots of water and Carbon Dioxide, and Methane to boot! AND we know that temperatures permitted liquid surface water in the distant past.
Is this reasonable? Could cyanobacteria have doomed Mars? anyone?
Evreything is indirectly solar power.
you forget radio nuclide decay heat...currently estimated to be about 1/2 of the heat in the earth.
According to what I learned in college: "If oxygen were to reach a value of 30% of atmospheric gas composition, fires would occur whenever a lightning bolt hit humid vegetation."u rrent/lectures/Gaia/#EXAMP
http://www.globalchange.umich.edu/globalchange1/c
So there is some truth to that.
This is what happens when consumer journalists are allowed to write stories about real science.
Newsflash: nearly all autotrophic life on earth (read: photosynthetic life, commonly known as plants) breaks down water when it creates glucose. Basically what the students have figured out is that cyanobacteria came up with a significant part of the chemical reactions that just about every plant on earth uses now, rather than those reactions evolving further down the chain.
The fact that this occured isn't new. at all. originally it was thought that the O2 that plants make came from the C02 they take in, but it was demonstrated quite some time ago that the plants actually split water and use the oxygens from that for the 02.
conclusion: cnet writers are idiots.
We're deeply offtopic here, but if you take a look at the title of that day's webcomic, it reads "Episode 476: Red Mage in the Cradle", obviously a reference to the book "Cat's Cradle" by Kurt Vonnegut. This novel, written in 1963, is where Ice-9 is orignally introduced as a theoretical form of water which solidifies at room temperature, and is thermodynamically preferred over normal ice. Since contact with it would cause all water everywhere to solidify instantly, Ice-9 has the potential to freeze the world solid, therby killing just about everything on Earth in the blink of an eye.
The book revolves around the pursuit of a small vial which may or may not contain a small piece of this incredibly powerful, incredibly dangerous substance, created by a very clever rogue scientist who didn't bother to consider the consequences of his actions. Written at the height of the Cold War, Ice-9, of course, is a stand-in for nuclear weapons... a technology which everyone wants to have, everyone wants the other side to *not* have, but one which, from a tactical standpoint, has no pratical application, since it can't be used without terrible consequences for all sides.
The man who does not read good books has no advantage over the man who cannot read them. - Mark Twain
You are partially correct. The cooling at the top of a mountain is due to the expansion of the air at high elevation. This takes energy and the energy is lost as heat.
However the trapping of the energy at the top of a mountain is what I am talking about. There is a greater amount of solar energy at the top of a mountain that at the sahara dessert for instance. This can easily be seen. The air absorbs solar energy. The solar constant in orbit is about 1.3 kw/m^2 and at sea level it is about 1.0 kw/m^2
The difference is what is absorbed by the atmosphere. And these numbers are from memory.
At the top of a mountain you have two processes working:
1) the energy is reflected back into space
2) there is not much up there to trap it
The lack of water vapour at high elevation is a critical factor. Get rid of the mountains and you have a number of factors that work together to warm up the planet.
I guess I am going to "troll to your troll."
The point of the Mann "Hockey Stick" is not so much as that there were warm and cold periods in the past beyond the horizon of human history. The point is that the climate has been dead flat for 1400 years and only in the last 100 or even 50 years has the climate warmed, suggesting an anthropogenic source. The other part of the Hockey Stick is that the Medievel Warm Period and Viking Greenland colony days were local and not global effects.
Trouble with the Hockey Stick is that the times past data is from tree rings and other proxies and has really big error bars. The recent past data is from meteorolgical temperature records with all of the attendent problems of heat islands and the like. The reason you don't do proxies for the recent past is that the numbers would be all over the place and wouldn't show the blade of the Hockey Stick. The reason you smooth the heck out of the proxy data is that, well, they are so noisy.
Then you have those two Canadians who pointed out that the flat part of the Hockey Stick may be an artifact of data handling, but, wouldn't-cha-know-it, the Canadians are not climate scientists, so we can safely disregard everything they point out.
Apart from the Hockey Stick, there are the climate modelers. I believe that their deal is that yes, water vapor is the main greenhouse gas, but the tropics are at 100 percent humidity anyway, so you won't get any more of it, so CO2 is the "swing vote on the court" if you will. They are also assuming strong positive feedback mechanisms -- is it that warming will release more CO2 from reservoirs? Is it that warming will release more H2O at higher lattitudes. I am kind of shakey on that part.
You know, I have heard it argued that it is not entirely clear that the rise in CO2 is anthropogenic. Yes, CO2 is rising as we cut down the rain forests and burn fossil fuel, but at only half the rate, and the rest must be going into sinks. Or maybe the sources and sinks are the dominant effect, and the increase in CO2 with civilization may only be correlative and not causitive. But there are an awful lot of people who are sure of themselves.