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Mass Extinctions from Global Warming?
uncleO writes "The current issue of Scientific American has an interesting article,
Impact from the Deep, about the possible causes for the five major global extinctions. It contends that only the most recent one was caused by a 'dinosaur killer' asteroid impact. Evidence suggests that the others were caused by 'great bubbles of toxic H2S gas erupting into the atmosphere' from the oceans due to anoxia." From the article: "The so-called thermal extinction at the end of the Paleocene began when atmospheric CO2 was just under 1,000 parts per million (ppm). At the end of the Triassic, CO2 was just above 1,000 ppm. Today with CO2 around 385 ppm...climbing at an annual rate of 2 ppm...to 3 ppm, levels could approach 900 ppm by the end of the next century."
There is one viable option to reduce oil dependancy : nuclear power.
Nuclear power (especially on its own) isn't going to do much to reduce oil dependency. It's not like much electricity comes from burning oil or derivatives.
Greenpeace founder supports nukes.. Watch The Inconvenient Truth, one of the salient points of the movie was we can make changes today, now that will in time have tangible effects, switching from coal to nuclear for example (also fyi coal also is highly radioactive , minute quantities of radioactivity x tons n tons of coal). Another equally important point with hydrocarbons worth billions if not trillions of dollars in the ground there is sufficient business for people to do anything possible to stem erosion in market share (cue the CO2 is life ad's) The bottom line is regardless of our 'understanding' of us being the causative agents or not, the CO2 levels are rising and this in turn will have adverse effects. Even if this were a result of polar bears farting if we can work to offset the excess to minimize impact, would that not be a sound move? Also regarding what we can do? cut down on power usage, energy saving appliances, the whole thread on slashdot and elsewhere on minimizing idle mode power consumption, energy efficient cars hybrid electric etc, flourescent lightbulbs etc etc. Bottom line there is no significant downside that i'm aware of to conservation and switching from hydrocarbons to the maximal extent possible, then why not do it?
Did you actually read what he did say? We have every reason to reduce emissions. I'm absolutely pro-emission-reduction; cleaner air is better for every living thing and that's a perfectly good justification to swing me. Seems to me he may actually want to reduce the emissions, just the hype around it is bad.
It's one thing to talk about increased H2S production, but that totally fails to address the question, "where did the O2 go?" The article describes the displacement of dissolved O2 by dissolved H2S in anoxic oceans, which is fine as far as it goes. However, unless large reservoirs of elemental carbon (or CO or CH4) are being oxidized to produce CO2 in large quantities, the result should be an increased atmospheric O2 concentration. Perhaps volcanic activity resulted in such an outpouring of CO2 that it dwarfed the O2 forced into the atmosphere by the anoxic oceans, resulting in the increased atmospheric CO2 concentrations inferred by the rock record. Or perhaps the inferred cause and effect relationship is not nearly as simple as the article makes it out to be.
Geology - it's not rocket science; it's rock science
Methane is a stronger greenhouse gas per molecule. But that doesn't mean it has a greater impact, since there is much less methane being released into the atmosphere.
As a funny side note: a significant amount (more than a third) of the anthropogenic methane emissions are coming from agriculture -- farting livestock basically.
But in those records the CO2 increases lag temperature increases by 800 years. So which causes which? Climatologists answer this by claiming that some unknown process starts the warming, and then, 800 years later, CO2 comes in and acts as a feedback to cause further warming. That's a rather murky explanation.
Finally: I've said this before, but perhaps was misunderstood:
-If we don't cut our carbon emissions (because we think we don't need to) and then turn out to be wrong, we may well end up like Venus.
-If we do cut them, we reduce our use of oil (which is in finite supply, as parent pointed out) and probably cut our costs (by energy efficieny stuff, my Mum works in that). Should we then turn out to be incorrect (i.e. CO2 isn't quite as bad as some of the doomsday predictions), we haven't really lost anything, but have gained quite a bit. Unfortunately, this is largely dependant on industry, and as the parent observed, convincing them may be difficult.
In short, either we will screw the atmosphere up with CO2, or we won't. Some people will inevitably pick sides and be wrong. In a matter with such potentially far-reaching implications, which way would you rather be wrong?
Don't you just hate it when people reply to your signature?
The idea is to build a standard low gradient heat platform that can be optimized for a geographical location's specific climate and geothermal features. The specific adaptation for arid regions utilizing absorption refrigeration especially shows promise.
Lots I want to reply to... :)
Probably the best source for scientific data and reliable modelling comes from the intergovernmental panel on climate change [ipcc.ch]. The last full report was from 2001 and is fully available on line and for free. I stupidly bought the books. The amount of synthesis of data performed is HUGE and from literally thousands of scientists in the field. It is truly the definitive work in progress. Due to the nature of science and the complex chaotic mechanisms of climate the models cannot be 100% conclusive; however, the four prospective models used have hypothesized the expected changes since 2001 fairly well. The four models assumed different scenarios of human responses to climate change. The four models being a reduction in CO2 emissions, constant increases, moderate increases and large increases in CO2 emissions. The effects of these models are classified according to a likelihood scale and associated percentages. Since the publication of the report, we have had 5 years to compare and contrast the models with reality. The modelling has done quite well. I suggest anyone who is interested read the synthesis report. The rest would take you a year or so to read
Since the report, due to the political tenderness of the topic, if anything, has been underreported and cautiously forwarded. It seems that one area that was underestimated in impact was the positive feedback mechanisms invovled in lost albedo and permafrost thaw. Also, the effects due to water vapor and cloud formation are still difficult to understand and predict.
As a teacher, I agree that we MUST listen and respond to the experts in the field and not political/religious/uninformed theorists. IE> michael Creighton and his ' State of Fear'. Some of the scientists he interviewed respond to his book at realclimate.org as well as a 'book report' in science magazine. Both are telling of the political nature of the topic.
Finally, we need to consider the larger manifestitions of 'global warming' with respect to increases in ocean acidity, altered weather patterns with respect to agriculture, etc. It is the unpredicatable spinoffs of global warming/climate change that will threaten society. Lack of food, lack of clean water and the wars associated with future conflicts we need to worry about.
I'm looking at buying farmland in Canada and Antarctica. ;-)
-jcr
The only title of honor that a tyrant can grant is "Enemy of the State."
One of things that we have to accept about humans is that they are part of nature. It's not natural for humans (as a population, not necessarily individuals) to restrain themselves.
What this means (to me) is that the destruction that humans brings (aka man-made) is also natural. It is also natural for humans to destruct to the point of no-return - i.e. humans will use up every last natural-resource until there is no longer a natural-resource to use.
Whaling and fishing are great examples. The Atlantic Ocean used to have an abundance of (sperm) whales. But the human race killed them off - that didn't stop the whalers of course. Rather than realizing the impact and looking for alternatives, they setup long complex shipping routes. Boats from Nantucket (North Eastern US) would set sail and round Argentina (South America) and then exploit the waters of Hawaii and Singapore in the Pacific. Eventually killing off the whales there as well.
The reason for hunting whales? Primarily whale blubber -which was boiled down to oil - which was used as a power source. Eventually the stock of sperm whales dried up in the pacific as well - forcing humans to come up with an alternative - which they did (petrol) - thereby officially killing the whaling industry. (Sure Japan is still at it - but mostly for the meat which focus on other types of whales).
The point is that humans will not restrain themselves or conserve (with some notable exceptions of course) their natural resources. And this is a natural part of human nature - which is part of nature.
So yeah - we are doomed to repeat the process (there are countless examples) and the end result is that we will wipe ourselves out. But that is part of nature - to thrive until starvation. Every population does it. Name one animal that does not gorge themselves - even if it means death to the species.....
-CF
Here's something that describes a theory and experiements by danish scientists. The statement that it is only in the US that people is arguing the global warming because of the oil industry is simply false and an easy way to discredit the research done by those who you do not agree with.
_ dad=portal&_schema=PORTAL
- Svensmark1998_0
These guys aren't saying that CO2 might not be one of the causes but that it might not be the biggest cause.
source: http://denmark.dk/portal/page?_pageid=374,931599&
"Results from an experiment, called SKY (Danish for 'cloud'), show that the released electrons significantly promote the formation of building blocks for cloud condensation nuclei on which water vapour condenses to make clouds.
Hence, a causal mechanism by which cosmic rays can facilitate the production of clouds in Earth's atmosphere has been experimentally identified for the first time.
The Danish research team, headed by Henrik Svensmark, officially announced their discovery 4 october 2006 in Proceedings of the Royal Society A, published by the Royal Society, the national academy of science, United Kingdom."
The place they performed the experiments: http://en.wikipedia.org/wiki/Cern http://public.web.cern.ch/Public/Welcome.html
"Global warming caused by cosmic rays?
It is known that low-altitude clouds have an overall cooling effect on the Earth's surface. Hence, variations in cloud cover caused by cosmic rays can change the surface temperature. The existence of such a cosmic connection to Earth's climate might thus help to explain past and present variations in Earth's climate.
Interestingly, during the 20th Century, the Sun's magnetic field which shields Earth from cosmic rays more than doubled, thereby reducing the average influx of cosmic rays. The resulting reduction in cloudiness, especially of low-altitude clouds, may be a significant factor in the global warming Earth has undergone during the last century."
More info here:
http://en.wikipedia.org/wiki/Solar_variation#_ref
Forget nuclear, have you not considreed energy efficiency? I reckon 90% of people I know use incandescent lightbulbs, probably 90% leave their PC monitor on at work overnight, 90% of them drive to the local shops rather than walk, 90% of them probably have the TV on standby over night (plus the phone charger, the video, the DVD, the set top box, the hi-fi and the home PC).
Energy efficiency is never mentioned, but we can save energy AND our own hard earned cash this way.I never understand why businesses dont invest in tech that auto shutdowns everyones PCs and monitors after 7PM.
And why does my PC have such a ludricous power supply anyway, especially when im just surfing, do I really need it all?
DRM-free indie games for the PC and Mac: Positech Games
I agree with a lot you are saying here, however my biggest concerns with powering our countries with nuclear power would be: 1) Where does all the radiactive waste get put? Here in Britain we're already having difficulty picking suitable sites for nuclear waste disposal. Infact, our government has ordered that sites be found multiple times and ignored all proposals anyway. Perhaps that just wouldnt be the case for America, you've got plenty of desert to store your deadly chemicals. I can see there being a lot of problems for countries too small to have any non-populated areas for waste disposal. 2) Terrorism. I don't pretend to know how effective a 747 crashing into a nuclear facility would be. But at the moment I would assume it could trigger a meltdown/explosion/distribution of nuclear material over a wide radius. (Someone with knowledge of this subject please reply to this). All my hopes lie in the ITER (International Thermonuclear Experimental Reactor) in France.
Android Software Engineer
Consider that to the right you would have extremist christians and catholics, people who would, at some point in time, find a way to get rid of anyone who wasn't white.
You live in a really weird fantasy world. Apparently you're a white middle class suburbanite type who doesn't know of the huge 'brown' population of Roman Catholics to the south of the United States.
It's reassuring to know my government is working at a reasonable pace to fix these issues
Government really isn't very good at 'fixing' anything. Goverment power is really a 'last resort' force that should be kept, as much as possible, out of business.
Your idea strikes me as overly complicated.
I come from an engineering family (my father builds dams, my uncle railways, and another uncle fighter jets) and I'm an ex-mech-eng who these days helps run the CPAN.
The current designs only need to solve three problem.
1. Build a concrete structure half a kilometre high in an area where land is cheap and weather is predictable.
2. Build some turbines into the structure that will require minimal maintenance.
3. Build a giant heat-absorbing green house to keep the convenction running 24 hours a day
And that's it!
No water needed, no complex enormous refrigerants, no underground cooling systems, no bi-directional fluid flows.
It works because it's SIMPLE and has no water or refrigerants, and almost no moving parts.
This is important beyond just the engineering, because it means that a solar tower has a similar economic profile to other giant concrete things with minimal moving parts, large up front costs and continuous income. Specifically, dams and toll roads.
So the same asset managers with billions to invest in toll roads and dams can also apply their same risk modelling to regular solar towers.
The same cannot be said for something with giant refridgerant flows moving all over the place. The engineering inefficiencies introduced would be huge, maintenance would be a nightmare, costs would balloon...
The solar tower planned in Australia has (from memory) a planned full time staff of 19. 17 of those 19 work in the gift shop and related tourism jobs.
The main tower will have only 2 full time employees outside of maintenance.
Can you say the same for the tower you propose?
The key there is "wild". You're right, you rarely see "wild" obese animals. Although the hippo - which has few natural predators and normally an abundance of food - may come close. Same with the adult walrus.
What you do see is animals gorging themselves in summer and sleeping it off in winter (we have some damn-fat squirrels in this area). Or you see animals gorging themselves and converting that energy into extremely powerful muscle.
Humans not only gorge themselves, but they also sit and watch TV.
Any animal that has an easy, abundant, food supply, AND no reason to motivate themselves to move, do become obese. There are plenty of non-mousing cats that lazily sit in window-boxes to sun themselves - getting up to do little more than eat. Dogs are the same way. Sure put them out in "nature" and they will slim down quickly - because hunting take energy, and the food source is not readily available.
Look at elk. They have little regard for the amount of grass they consume. The only thing that keeps them in check is the size of their mouth and the number of calories it takes to maintain their weight. When they decimate a meadow they move on. "Moving on" makes them expend more energy. Take away their food source (do to drought or human development) and they become skin and bones. Elk don't hibernate and they loose tremendous amount of body weight during the winter - when spring comes what do they do? They fatten up, and keep fattening up right on until the next fall when food starts to become sparse. Do they moderate themselves? Not by choice - it's simply a supply thing.
Does what I say mean that we shouldn't try? No - I never said that. I do think that saving our environment is worthwhile - I mean I don't want to be sick while I'm here. But I also think we are fighting nature, rather than fighting on behalf of nature.
Short-sightedness is not realizing the realities. The big picture is that the human race will not last forever.
-CF
...as seen over the last 500 million years.
/ image277.gif over the last 500+ million yers of CO2-levels and temperature You will maybe get the impression that the humanitys CO2-production is not the main climate factor.
Both the temperature and CO2-levels are at an all time low value.
And the correlation between temperature and CO2 is very weak at best.
If You look at the diagram http://www.geocraft.com/WVFossils/PageMill_Images
Mundus Vult Decipi
Make things up in the present! Here is our best understanding of causes of the past mass extinctions:
There has never been an extinction event caused by global warming. Warmth is conducive to life.
an ill wind that blows no good
...is just a con to get the federal government to adopt fuel efficiency standards. That will force people to drive smaller cars, which will force them to have smaller families. It's just a conspiracy to impose involuntary birth control by a bunch of latte-swilling liberals who hate children!
Sounds like I'm flamebaiting, right? But that's pretty much the party line with the Eagle Forum crowd.
I'm not totally convinced that "passivated glass brick" is the optimum waste disposal. It's certainly, however, better than what we do with coal (dump it into the atmosphere). I'm also not convinced that it's feasible to safely bury CO2. Some of those disposals have failure modes that are quite frightening.
To me an optimal disposal method for radio waste would packetize it in a way that would allow it to be recovered if that became economically viable. (Say, for use in a fast-breeder.) But you also want it dispersed so that it didn't undergo "mini-chains" that caused it to burn itself up too quickly. Small blobs in flat sheets separated by about a foot (of plaster? cement?) sounds good. The sheets could be as large as is convenient to handle. Some PVC mimic would be a good choice for what to make them out of. That way they could be loosely rolled for transport. (Unless someone things it worthwhile to build a cadmium spiral cylinder to store them in. Or to transport them flat separated by cadmium sheets. Not likely. Just keep them separated, and make sure that no one sheet will go critical even if you roll it tightly--and then ensure that it is rolled loosely (with styrofoam spacers?. (That should be easy. This is waste, not fuel.)
The thing is, while the stuff is encased in plastic it's only dangerous to folk that are near it. It's not explosive. So you need to keep it cool enough to not melt the plastic...but you've already used it as throughly as is reasonably economic, so it's not super hot thermally.
OTOH, if you just want it to go away and never return, then passivated glass bricks are hard to beat. You could even use them to pre-heat water for a steam plant for the first decade or so. (I'm presuming that the passivation includes something like sealing the bricks in paraffin so that water can't leach through... if you plan for that, then you don't need to worry about it's happening accidentally. Then put the bricks in a plastic bag before you dump them in the water to heat it, and all should be well.)
I think we've pushed this "anyone can grow up to be president" thing too far.
This looks to me like large-scale speculation based on scant evidence. For example, while they give a plausible cause for increased H2S, they have ignored the simultaneous presence of excess iridium. Here is an alternative theory: The asteroid impacts imparted enough energy to disturb balances at the edges of the tectonic plates, dramatically increasing volcanic activity for a time, which would account for BOTH the iridium, AND the H2S. Thus the H2S would be a symptom, not a cause.
hmm...."by the end of the next century"
since it's the beginning of this century, that indicates the prediction is nearly 200 years in the future..
just as an exercise, let's see what the state of mankind was 200 years ago...
lewis and clark were exploring the west (no states west of the mississippi)
Napoleon invades Berlin (now there's a twist!)
War of 1812 U.S. vs. Britain
semaphore system developed (internet?, heck folks were waving flags around to move data)
first battery invented
little ice age ends
civil war
ottoman empire
postage stamp invented
i hardly think those alive 200 years ago were in any position to predict what mankind's situation, much less the weather was going to be like in 200 years. likewise, it's preposterous on it's face, to assume any prediction 200 years into the future will be accurate.
in 200 years, i don't think we have any idea what the energy producing technologies will consist of.
Yeah totally agree with parent, methane is really a much bigger danger. Personally I'm very concerned with the enormous methane hydrate deposits at the North Pole and Siberia which are currently kept in check by the ice caps and permafrost. We need to know more about the stability of these deposits because if they start to outgas not only will we see some quite horrendous local extiction events, but the warming could accelerate substantially in a positive feedback cycle.
God was my co-pilot, but then we crashed and I was forced to eat him.
Of all the greenhouse gases, CO2 is, by a considerable margin, the most significant.
e _greenhouse_gases
Apart from water vapor itself, of course (which is -possibly- three times more important than CO2):
http://en.wikipedia.org/wiki/Greenhouse_effect#Th
*Whether* our activities are a contributing factor isn't in question,only extent; the question is 1) whether we have the time and power to change our activities to minimize our contribution; 2) whether we can agree on appropriate actions in time to choose them rationally instead of having them thrust upon us by fate.
The rest is out of our hands.
"You must try to forget all you have learned. You must begin to dream." -- Sherwood Anderson
a) acidification through CO2 adsorption onto minerals (particularly in the ocean and soil) via molecular diffusion. Surf makes for a large and actively mixing surface area... Structures built from calcium carbonate are dissolved (there are a number of important calcifying photoautotrophs); ion transport mechanisms are stressed because of a change to the concentration gradient (coccolithophores suffer from this, and they are among the most abundant ocean photosynthesizers). Few sea organisms adapt to increases in carbonic acid in their environment; forests are regularly sterilized by volcanic CO2 emissions that increases ground level CO2 and consequently soil CO2 and decreases soil pH.
b) parallel evolution has resulted in a number of important enzymes that have binding affinity for both O2 and CO2 depending on relative concentrations. While RuBisCO is the most obvious of these in Calvin Cycle organisms (like plants), it is not the only one; others act as limiting factors on carbon fixing by RuBisCO often by keeping Mg+ ions from the RuBisCO's active site or influencing the rapditiy of the formation of the carbamate. This is often done to preserve particular enzyme conformations under environmental stress (most notably temperature) the organism's ancestors survived, and can be counterproductive in the current environment.
In animals with haemoglobins or analogues, there are similar binding affinities for both CO2 and molecular oxygen under various conditions including the relative concentrations of the two. Greenhouses containing plants which survive 1% concentrations of CO2 for several hours can be entirely freed of animal pests. However, it also can destroy useful soil animals and bacteria, including a few symbiotic species which fix nitrogen...