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This is all from the ethomas website:

There was a prolonged period of higher-than-average rates of extinction (over several millions of years
Topped of by an extinction of many species within a few hundred thousands of years, possibly even within a few ten thousands of year.

New theory: methane hydrates dissociate: CH4 + 2O2 -> CO2 + 2H2O (Note: methane, CH4, is a greenhouse gas)

Why warming? How did it cause extinction?
Long-term warming (a few millions of years): CO2 from Siberian flood basalts

Long-term warming caused dissociation of methane hydrates -> more greenhouse effect, more warming -> more methane hydrate dissociation, etc. (positive feedback effects)

Land: poisoning volcanic fumes, changes in climate
Impact may have complicated matters..


This all seems to suggest that the methane itself didn't directly lead to mass extinction, but was one in a list of possible causes of global warming. The extinction period lasted for a very long time (geological record) at least in the thousands of years. I would think that a giant methane explosion, one larger than all our combined nuclear cache (as suggested in the first link) would probably kill nearly instantaneous.

It seems that Ryskins theory is on one extreme while others accept that a series of smaller explosions or just a steady leak of thawed methane from the ocean floors(without explosion) could be one of many possible factors for global warming.



EDIT: Spellings and Boldages

Last edited by mattyboombatty at 09-Dec-2004 13:30

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Critical Fertilator: The Micromanager of Macronutrients

Cup, if you remember correctly, that happened a long time ago (in a galaxy far, far away). Anyways, I hope you are right.

Angelzoo, you have the right idea. Though they don't quite photosynthesize as much as a tree, any live/growing plant will help, including your flowers. Thanks for taking the time to read my article.

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Critical Fertilator: The Micromanager of Macronutrients

For every tank full of gas we buy, we should try to buy and plant another plant.

Does a basket of live flowers, or potted foliage count, or does it have to be a tree? I'm limited to what I can have on my balcony, lol.

Good post, a lot I've thought of from time to time, but it's still good to focus on again and again.

I definitely agree that global warming has the potential to be destructive (those ice caps don't look too happy right about now...), but by then, we'll be on our way to tatooine to aid the rebel alliance in their fight to secure the universe from the evil grip of the empire--I hope .

Thanks Cup,

Well like it said in the article, if an asteroid hit earth in the ocean, there likely wouldn't be any evidence, except for the buckyballs, I guess. Thanks for clearing that up. I guess I'd have to agree that there are more likely causes of such a rapid mass extinction.

Generally speaking, global warming could be just as devastating over a longer period of time, if we don't do anything about it and keep blindly polluting the atmosphere. Which is really what I was trying to get at in the article. Also, as you said before, there are other, more direct ways we are hurting the environment as well.

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Critical Fertilator: The Micromanager of Macronutrients

Oh, I could have sworn you stated that the nutrients were lacking in the lower half of the water column. Guess I need to read more carefully.

I'm pretty sure it is currently being disputed as to whether or not the cause of the extinction was methane buildup or an ET projectile. Most paleontologists now believe in the asteriod impact theory, but as of yet, there has been no physical evidence (i.e. an actual impact site) to vallidate this theory, unlike the Cretaceous dieoff. However, the methane argument also has a great deal of very convincing evidence going for it.


Last edited by Cup_of_Lifenoodles at 10-Dec-2004 09:33

Ok, I'm a little confused.

Site 1: http://dsc.discovery.com/news/briefs/20030901/methane.html
Methane build up in the ocean --->released, someone lights a match and BOOM. Everybody dies.

Site 2: http://ethomas.web.wesleyan.edu/wescourses/2004s/ees227/01/ptextinction.htm

multiple effects add up to cause one large dieoff.

Site 3:
http://www.sciencenews.org/articles/20010224/fob1.asp
Buckyballs containing trapped gasses are found in the geological record, suggesting an extraterrestrial impact.


Am I right on this? If so, which is the accepted theory? If not, where am I wrong?

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Critical Fertilator: The Micromanager of Macronutrients

Most nutrients tend to find their way to the bottom of this very deep lake. Normally, a decrease in surface temperature will cause the cooler water to sink, and warmer water to rise, bringing nutrients towards the surface. This effect is called upwelling, and due to the increased stability of surface temperatures, this effect is no longer occurring as frequently, diluting the nutrients available near the surface of the lake.

Upwelling brings nutrients up, while a thermocline reduces upwelling, keeping nutrients at the bottom.

I suppose enough methane could be toxic enough to induce mass extinction, but I haven't read anywhere other than what you sent me that the extinction is directly linked to toxicity of methane in the atmosphere. I've read through 15 sites on the permian extinction and 2 have mentioned methane toxicity as a possible cause. Most list probable causes as volcanism, glacier melt, meteorite impact, and global warming. I agree it could have happened, but from what I've read it doesn't seem to me that it is THE accepted cause.

EDIT: sorry my post at 5:55 dec 9th, is confusing I will fix it. I was a little tired that morning. But taken from my first post, there is little confusion.

Last edited by mattyboombatty at 09-Dec-2004 21:13

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Critical Fertilator: The Micromanager of Macronutrients

Right, but had the methane not reacted, very little would have died out from such a degree of warming. Also, what I got from you was that the nutrients, rather than cycling to the bottom, are stuck on the top, which ir rarely, if ever, the case.

edit: spelling and content

Last edited by Cup_of_Lifenoodles at 09-

Last edited by Cup_of_Lifenoodles at 09-Dec-2004 20:23

It is also proposed that an increase of 5 degrees was needed in order to release the frozen methane from the ocean, and this, then resulted in another large change in temperature.

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Critical Fertilator: The Micromanager of Macronutrients

Effect of Global Warming on Tropical fish

“Reporting in the August 14, 2003, issue of the journal Nature, Catherine O'Reilly of Vassar College, Andrew Cohen of the University of Arizona, Simone Alin of the University of Washington, Pierre-Denis Plisnier of the Royal Museum for Central Africa in Belgium, and Brent McKee of Tulane University in Louisiana, announce that climate change in the region is harming Lake Tanganyika's ecosystem.”

Global warming?

Due to increased amounts of greenhouse gasses such as CO2 from anthropogenic (man made) sources, more of the sun’s energy is being trapped in the Earth’s atmosphere as heat. This global warming is causing climate change all over the Earth in every biome, and in every ecosystem. Already, most of the Earth has experienced increased average temperature of 1 to 3° Celsius. Due to this temperature rise, precipitation patterns are also likely to change, or shall I say, continue to change.

So what? Winter is going to be a little less chilly.

This is true, however all living organisms have a range of temperatures they have adapted to, humans included. Right now many different species of animals have been observed showing different behavioral patterns, such as early migration, later hibernation, and shifted mating seasons. These behaviors are all cued by temperature and/or precipitation. These changes can negatively affect these species if other organisms they depend on are not changing with them. Many animals have already started to pack up their belongings and move north, invading and disrupting other ecosystems because they cannot cope with the higher temperatures in their native range. Still not concerned? This increase in temperatures may not seem drastic, a couple of degrees over a hundred years. However, geologists and biologists have worked together and found a mass extinction period millions of years ago where over 90% of ALL species living on the earth died out, completely. How could this happen? These scientists have linked this mass extinction to a SIX degree Celsius increase over THOUSANDS of years.

I thought this was about tropical fish.

Ok, Ok. To the point. The previously mentioned scientists have tracked surface temperature of Lake Tanganyika in Africa for the last eighty years. These temperatures coincide with the .6° C increase in air temperature near Lake Tang. Before you get excited, saying “That’s nothing compared to the 6° increase mentioned earlier,” you have to realize that near the equator temperatures are much more stable. Where here in Buffalo, NY, I might experience a 40° C range over the entire year, tropical regions will generally only experience a range of about 2-4° C all year. Contrary to what you might think, this increase in temperature actually stabilizes the range of temps experienced by the surface of the lake. Again, don’t get excited. You might think that you keep your fish tank pretty stable all year, but your fish tank isn’t quite as deep as the Tang rift lake. Most nutrients tend to find their way to the bottom of this very deep lake. Normally, a decrease in surface temperature will cause the cooler water to sink, and warmer water to rise, bringing nutrients towards the surface. This effect is called upwelling, and due to the increased stability of surface temperatures, this effect is no longer occurring as frequently, diluting the nutrients available near the surface of the lake. While algae is unsightly and a nuisance in our tanks, it is a source of food for some fish, and for base organisms that fish feed off of. These algae need the nutrients from the bottom of the lake to grow, but are no longer receiving them at a sufficient rate. Algae production has decreased over 20% during the 80 years the scientists have been monitoring Lake Tanganyika, and a coinciding decrease in fish abundance of 30% has also occurred.

This is only one effect that Global warming can have on Tropical fish. Where waters run a little less deep, say the Amazon, temperatures are going to increase more, possibly out of the acceptable range for most fish. Whereas land animals might be able to pack up and leave, fish are a little more restricted in which directions they can go, if anywhere at all. Another effect of global warming includes precipitation change, resulting in possible drought. This effect, coupled with a higher evapotranspiration rate from plants (rate at which water is expelled due to photosynthesis) due to higher temperatures, might cause an overall loss of fresh water, concentrating toxins present in the natural bodies of water.

How does this effect us/why should we care?

Though I think the effects of less available wild fish on us as hobbyists are pretty straightforward, I thought I’d lay it out. Wild caught trops, those not bred in farms are likely to become much more expensive, less common, or disappear altogether. Forget about already rare species, species that are pretty common now, might not be traded in the near future.

What can we do?

Most of the greenhouse gasses in the atmosphere are now attributed to anthropogenic causes. Think fossil fuels, industry, and power plants. As for major industry, we are not allowed to discuss politics so we will stay away from that, but think about it. However, A good way to start is with yourself. Try to think about Babelfish driving around in her hybrid car getting a million miles to the gallon. We should all be using fluorescent lights for our fish as well as in our homes; they are also cheaper to run. Try to conserve what energy you can, everyone counts. Car emissions and energy use by people like you and me account for nearly 40% of new greenhouse gasses. Plant trees! Plants are a major CO2 sink, as the folks that visit the “planted aquarium” forums know.




Last edited by mattyboombatty at 08-Dec-2004 21:25

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Critical Fertilator: The Micromanager of Macronutrients

http://dsc.discovery.com/news/briefs/20030901/methane.html
http://ethomas.web.wesleyan.edu/wescourses/2004s/ees227/01/ptextinction.htm
http://www.sciencenews.org/articles/20010224/fob1.asp

The presumed climate change likely resulted from the methane explosion (buckyballs--just look it up online), but most life had already been eradicated by then.

I'm not sure that the thermocline itself kills anything, but what dies off does sink to the bottom. Usually the cooler surface water would force warmer water from below, say at night or in the winter, bringing the nutriennts up with it. [edit]Due to the thermocline there is no cycling of the water to bring up the nutrients from the depths, and will be stuck at the bottom of the lake.[/edit]

[from origianl]Nutrients will then be stuck at the bottom, and due to the thermocline, there is no cycling of the water to bring up the nutrients from the depths.[end original]

Do you have any links or sources for the chemical extermination? I haven't seen anything about that and would like to read about it. All I've read are proposed theories of volcanism, ocean salinity and volume shifts, and climate change.

Last edited by mattyboombatty at 09-Dec-2004 21:15

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Critical Fertilator: The Micromanager of Macronutrients

I see where you're getting at, but, I thought thermocline was always the other way around, as in, the heat causes a large bacteria/pelagic crustacean die off, their corpses henceforth sinking into the depths. Yet the current, as you said, cannot really weave it's way that deep, and therefore the nutrients are isolated at the BOTTOM, not the top. Maybe I'm just confused. Also, I'm pretty sure the currently accepted theory of permian/triassic extinction was that of chemical extermination.



Last edited by Cup_of_Lifenoodles at 09-Dec-2004 00:31

Also, this is somewhat of a research paper, not entirely from one article. I have many secondary sources (journal articles written by known reputable sources) and while predictions, past and future are merely theoretical, the thermoclines and dissapearance of upwelling is factual.

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Critical Fertilator: The Micromanager of Macronutrients

You are right that global warming isn't the only cause, but it is a cause. And an increase in surface temperature does not mean a significant overall temperature change. This is called thermocline. The top water stays warm, and is not allowed to sink because heat rises.

I was talking about the permian, and you are right, I misread 90 something percent of marine life and 3/4 of land vertabrate families. Still pretty devastating. However, this extinction may be said to be caused by volcanic eruptions, but the eruptions caused climate change, an estimated six degree change over a very long period of time. The temperature change can account for the change in salinity in the oceans which destroyed marine life.



Last edited by mattyboombatty at 08-Dec-2004 22:42

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Critical Fertilator: The Micromanager of Macronutrients

Interesting read. However, I don't think global warming (as bad as it is) is the only thing to blame. While the argument may be vaild, I don't think surface temps has that great of an impact as a whole on the ecosystem. Water circulation should be maintained at a fairly consistent level, as colder waters at the surface are still warmer than the bottom of the lake, therefore very little should sink to the bottom. An increase of surface temp also indicates an overall increase in lake's temperature, so the temperature difference should be pretty much the same. Considering how we have released damaging feral species, exploited the region for mining and agriculture, flush the lake with untreated sewage and aided in increased acidification of the area, there's no wonder as to why the fish are dying off.
Also, there has never, in the history of the earth, been a mass extinction which wiped out 90% of all life. I'll assume the author was talking about the Ordovician extinction, biologically one of the worst (some would argue, THE worst) extinction to ever take place. Others believe the Permian extinction was the most castastrophic, but one can never know for sure uless he or she lived during the time period (I have heard some individuals claiming the aforementioned period wiping out such a percentage of organisms, but that is only tallying marine species. A simple family extinction rate per millions of years plot can show that number is quite off). Neither of the two are believed to be *chiefly* caused by temperature fluctuations.

EDIT: Spellingage

Last edited by Cup_of_Lifenoodles at 08-Dec-2004 22:13

Thank you Tryst

Not only is the arctic supposed to disappear, but most of the tundra as well. It's very sad really that most people beilive it is hooey, when more and more scientific data is being discovered in favor of the theory all the time.

I think the Europeans should take great intrest, as they could very possibly be the Sahara desert in about 100 years. Italy and Greece have already been feeling the effects...

Last edited by mattyboombatty at 08-Dec-2004 20:43

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Critical Fertilator: The Micromanager of Macronutrients

Thanks for posting this matty.

I agree 100%, we all need to look at ways we can reduce the emission of greenhouse gases while we are still able to make a difference. Global warming has been a bit of a hot topic here in Canada recently, as new studies have shown that the arctic is melting at an alarming rate. With the way things are going now, polar bears may be extinct in as little as 10 years due to the effects of global warming. A lot of people laugh about it, as the problem has been minimized a lot in the media, but it's something that really needs to be taken seriously. The problem seems really magnified in the arctic here, where our inuit populations are reporting drastic climate changes.