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Dr. Mabuse
Septic Fiend
Sweden
9696 Posts |
 Posted - 12/04/2008 : 15:03:49 [Permalink]
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Originally posted by chaloobi
A few thoughts:
#1. I'm one of those who say it's too late to stop substantial warming in the coming century. And I only say that because I believe it is. |
Release of methane from a thawing Siberian tundra is cause of alarm. There's much green house potential in that methane. Halting the warming before that release is preferable.
#2. There really isn't a balance of any kind in nature. It just seems that way because all the myriad changes that are in process all the time occur too damn slowly (or our life-spans are too damn short) for humans to notice. Until now. |
When I look at CO2-graphs, it certainly seems to me like there is a measure of balance in the amount of CO2 in the atmosphere.
#3. About the 3 mile ice, that was supposed to be light hearted. However, if it's true that we're overdue for the next glaciation, and that the reason is the methane and CO2 human activity has been puffing into the atmosphere over the past 5-8k years, then we ought to be cautious about how much we reduce those gasses to address the current gigantic puff spike.
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True, but no one is proposing to return to pre-industrialised (or even pre-agricultural) levels within a very short time span, say 10 years. Both methane and CO2 takes its time to get re-integrated into the biomass. Once we start reducing the release of these green house gasses, we will be able to measure the effects in the atmosphere and in global temperatures. |
Dr. Mabuse - "When the going gets tough, the tough get Duct-tape..."
Dr. Mabuse whisper.mp3
"Equivocation is not just a job, for a creationist it's a way of life..." Dr. Mabuse
Support American Troops in Iraq:
Send them unarmed civilians for target practice..
Collateralmurder. |
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Dude
SFN Die Hard
USA
6891 Posts |
Posted - 12/04/2008 : 17:26:35 [Permalink]
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We are at the end of a glaciation period, not the start of a new one, geoligically speaking. Remember, its only been 10,000-15,000 years or so since the ice sheets retreated to altitude and off the plains. A mere blink in geo-time.
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Ignorance is preferable to error; and he is less remote from the truth who believes nothing, than he who believes what is wrong.
-- Thomas Jefferson
"god :: the last refuge of a man with no answers and no argument." - G. Carlin
Hope, n.
The handmaiden of desperation; the opiate of despair; the illegible signpost on the road to perdition. ~~ da filth |
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chaloobi
SFN Regular
1620 Posts |
Posted - 12/05/2008 : 06:28:59 [Permalink]
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Originally posted by Dude
We are at the end of a glaciation period, not the start of a new one, geoligically speaking. Remember, its only been 10,000-15,000 years or so since the ice sheets retreated to altitude and off the plains. A mere blink in geo-time.
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From what I've read, we have been in an ice age for 4+ million years. What that has meant is long (100k year) periods of glaciation where the northern hemisphere is covered by ice sheets and short (10-15k year) warm periods where the ice retreats. These periods are determined by the interaction of two orbital cycles and one rotational cycle that come together to cause the warm periods. But the norm is glaciation. We're past the end of the latest warm period right now and ice should be returning. But it's not because we've interupted it. I'll try to find a link on this - I had one to the research that suggests the agricultural revolution interupted the glaciation cycle but it might be at home.... |
-Chaloobi
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| Edited by - chaloobi on 12/05/2008 07:02:42 |
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chaloobi
SFN Regular
1620 Posts |
Posted - 12/05/2008 : 07:01:18 [Permalink]
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Originally posted by Dr. Mabuse
Originally posted by chaloobi
A few thoughts:
#1. I'm one of those who say it's too late to stop substantial warming in the coming century. And I only say that because I believe it is. |
Release of methane from a thawing Siberian tundra is cause of alarm. There's much green house potential in that methane. Halting the warming before that release is preferable. |
I'm more alarmed about the acidification of the oceans. That could trigger something much more terrible than anything the warming might cause.
Regarding the warming - the atmosphere's already primed with enough greenhouse gas for a hundred years of warming even if we did something for real today, which we're not. With that in mind, observed phenomenon have tended to be faster and more severe than the models have predicted. Climate scientists have had to be very cautious due to the politically charged nature of this issue in the US and have likely been over conservative with those models. So IMHO we're in for at least a hundred years of climate change that will be greater and occur faster than anyone has predicted so far and it's already too late to do anything about it.
| #2. There really isn't a balance of any kind in nature. It just seems that way because all the myriad changes that are in process all the time occur too damn slowly (or our life-spans are too damn short) for humans to notice. Until now. |
When I look at CO2-graphs, it certainly seems to me like there is a measure of balance in the amount of CO2 in the atmosphere. |
If you look at the graphs of gas concentrations they got from the Greenland ice cores, CO2 and methane go up and down in ~120k year cycles in sync with the glaciation. It never stays constant over very long periods of time and has indeed never been constant through all of human history.
#3. About the 3 mile ice, that was supposed to be light hearted. However, if it's true that we're overdue for the next glaciation, and that the reason is the methane and CO2 human activity has been puffing into the atmosphere over the past 5-8k years, then we ought to be cautious about how much we reduce those gasses to address the current gigantic puff spike.
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True, but no one is proposing to return to pre-industrialised (or even pre-agricultural) levels within a very short time span, say 10 years. Both methane and CO2 takes its time to get re-integrated into the biomass. Once we start reducing the release of these green house gasses, we will be able to measure the effects in the atmosphere and in global temperatures. |
It wouldn't surprise me if over the next hundred years we migrate all of our energy sources to electrical generation from fusion or orbital solar. When the greenhouse gas load leaves the atmosphere, will the climate return to it's natural galciation cycle? In 500 years will there be glaciers advancing across Northern Canada? Yeah, yeah, I know that's scifi pipe dream stuff since we can't even get our heads out of our assess enough to do even the minium, but the idea that warming isn't 100% bad is something to keep in mind in the event we ever make long term plans for civilization. |
-Chaloobi
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chaloobi
SFN Regular
1620 Posts |
Posted - 12/05/2008 : 07:43:12 [Permalink]
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Originally posted by chaloobi
Originally posted by Dude
We are at the end of a glaciation period, not the start of a new one, geoligically speaking. Remember, its only been 10,000-15,000 years or so since the ice sheets retreated to altitude and off the plains. A mere blink in geo-time.
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From what I've read, we have been in an ice age for 4+ million years. What that has meant is long (100k year) periods of glaciation where the northern hemisphere is covered by ice sheets and short (10-15k year) warm periods where the ice retreats. These periods are determined by the interaction of two orbital cycles and one rotational cycle that come together to cause the warm periods. But the norm is glaciation. We're past the end of the latest warm period right now and ice should be returning. But it's not because we've interupted it. I'll try to find a link on this - I had one to the research that suggests the agricultural revolution interupted the glaciation cycle but it might be at home....
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Interseting. Wikipedia cites information that contradicts what else I've read (I'll find the link if I can later):
Glacials and interglacials
See also: Interglacial
Shows the pattern of temperature and ice volume changes associated with recent glacials and interglacialsWithin the ice ages (or at least within the last one), more temperate and more severe periods occur. The colder periods are called glacial periods, the warmer periods interglacials, such as the Eemian Stage.
Glacials are characterized by cooler and drier climates over most of the Earth and large land and sea ice masses extending outward from the poles. Mountain glaciers in otherwise unglaciated areas extend to lower elevations due to a lower snow line. Sea levels drop due to the removal of large volumes of water above sea level in the icecaps. There is evidence that ocean circulation patterns are disrupted by glaciations. Since the Earth has significant continental glaciation in the Arctic and Antarctic, we are currently in a glacial minimum of a glaciation. Such a period between glacial maxima is known as an interglacial.
The Earth has been in an interglacial period known as the Holocene for more than 11,000 years. It was conventional wisdom that "the typical interglacial period lasts about 12,000 years," but this has been called into question recently. For example, an article in Nature[10] argues that the current interglacial might be most analogous to a previous interglacial that lasted 28,000 years. Predicted changes in orbital forcing suggest that the next glacial period would not begin before about 50,000 years from now, even in absence of man-made global warming [11] (see Milankovitch cycles). Moreover, anthropogenic forcing from increased greenhouse gases might outweigh orbital forcing for as long as intensive use of fossil fuels continues[12]. |
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-Chaloobi
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Simon
SFN Regular
USA
1992 Posts |
Posted - 12/05/2008 : 09:11:13 [Permalink]
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| I'm more alarmed about the acidification of the oceans. That could trigger something much more terrible than anything the warming might cause. |
I am not sure... How much CO2 doest it take to change the pH of water significantly? Keeping in time that most organisms can handle a reasonable variation in pH. |
Look again at that dot. That's here. That's home. That's us. On it everyone you love, everyone you know, everyone you ever heard of, every human being who ever was, lived out their lives. The aggregate of our joy and suffering, thousands of confident religions, ideologies, and economic doctrines, every hunter and forager, every hero and coward, every creator and destroyer of civilization, every king and peasant, every young couple in love, every mother and father, hopeful child, inventor and explorer, every teacher of morals, every corrupt politician, every "superstar," every "supreme leader," every saint and sinner in the history of our species lived there – on a mote of dust suspended in a sunbeam.
Carl Sagan - 1996 |
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Dude
SFN Die Hard
USA
6891 Posts |
Posted - 12/05/2008 : 10:16:51 [Permalink]
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chaloobi, the wiki article reflects what I had learned concerning the interglacial periods. Sorry I didn't throw in a reference or link to something! Busy week.
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Ignorance is preferable to error; and he is less remote from the truth who believes nothing, than he who believes what is wrong.
-- Thomas Jefferson
"god :: the last refuge of a man with no answers and no argument." - G. Carlin
Hope, n.
The handmaiden of desperation; the opiate of despair; the illegible signpost on the road to perdition. ~~ da filth |
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chaloobi
SFN Regular
1620 Posts |
Posted - 12/05/2008 : 11:27:18 [Permalink]
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Originally posted by Simon
| I'm more alarmed about the acidification of the oceans. That could trigger something much more terrible than anything the warming might cause. |
I am not sure... How much CO2 doest it take to change the pH of water significantly? Keeping in time that most organisms can handle a reasonable variation in pH.
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I just heard an article about this on NPR and they've very recently seen a sudden and large drop in pH. They seemed to think this was a pretty big deal. I'll see if I can find reference to it.
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-Chaloobi
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Dr. Mabuse
Septic Fiend
Sweden
9696 Posts |
Posted - 12/05/2008 : 11:39:07 [Permalink]
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Originally posted by chaloobi
Originally posted by Dr. Mabuse
When I look at CO2-graphs, it certainly seems to me like there is a measure of balance in the amount of CO2 in the atmosphere. |
If you look at the graphs of gas concentrations they got from the Greenland ice cores, CO2 and methane go up and down in ~120k year cycles in sync with the glaciation. It never stays constant over very long periods of time and has indeed never been constant through all of human history.
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Indeed. I'd like to emphasise "in sync with the glaciation". Depending on the over all state of the climate, methane and CO2 reach a level of equilibrium. Quantities remain fairly constant with regards to that particular time and climate, and the over all trend of the climate change. Not so today: levels are spiking unprecedentedly, way off the norm.
It wouldn't surprise me if over the next hundred years we migrate all of our energy sources to electrical generation from fusion or orbital solar. When the greenhouse gas load leaves the atmosphere, will the climate return to it's natural glaciation cycle? In 500 years will there be glaciers advancing across Northern Canada? Yeah, yeah, I know that's scifi pipe dream stuff since we can't even get our heads out of our assess enough to do even the minium, but the idea that warming isn't 100% bad is something to keep in mind in the event we ever make long term plans for civilization.
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Drowning the atmosphere anew with greenhouse gasses is a minor feat in the grand scope of things, if we want to keep warm. All we have to do is increase our fossil fuel pollution and methane-farting live stock. |
Dr. Mabuse - "When the going gets tough, the tough get Duct-tape..."
Dr. Mabuse whisper.mp3
"Equivocation is not just a job, for a creationist it's a way of life..." Dr. Mabuse
Support American Troops in Iraq:
Send them unarmed civilians for target practice..
Collateralmurder. |
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chaloobi
SFN Regular
1620 Posts |
Posted - 12/05/2008 : 11:46:16 [Permalink]
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Originally posted by chaloobi
Originally posted by Simon
| I'm more alarmed about the acidification of the oceans. That could trigger something much more terrible than anything the warming might cause. |
I am not sure... How much CO2 doest it take to change the pH of water significantly? Keeping in time that most organisms can handle a reasonable variation in pH.
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I just heard an article about this on NPR and they've very recently seen a sudden and large drop in pH. They seemed to think this was a pretty big deal. I'll see if I can find reference to it.
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Ok, here's the article I heard:
http://www.npr.org/templates/story/story.php?storyId=97412198
Mussels Lose Out As Carbon Dioxide Changes Ocean
by Richard Harris
Morning Edition, November 25, 2008 · All the carbon dioxide pouring into the atmosphere is making the oceans more acidic — and those effects appear to be striking very close to home.
Scientists have been fretting about what ocean acid will do to coral reefs and certain species of plankton. And a new study now documents a startling and rapid change in ocean acid on an island just off the coast of Washington state.
Ocean chemistry measured from Tatoosh Island found that the ocean there is becoming acidic 10 times faster than expected, according to a study published in the Proceedings of the National Academy of Sciences. And the study's author J. Timothy Wootton says the island's ecosystem is changing rapidly as a result.
During an eight-year period, he says, 10 to 20 percent of the mussels on the island have been replaced by acid-tolerant algae.
"When we project where these shifts are going in the long run, they're actually pretty alarming," Wootton says.
Given this trend, he expects 60 to 70 percent of the mussels on the island to disappear in the coming decades.
"The demise of mussels as a dominant species is potentially a pretty big deal," Wootton says. Mussels provide shelter for many animals that live along the tide line. They form a key part of the food web that includes the fish we eat.
Wootton isn't sure why the acidity changed so rapidly on this island. One lesson, though, is that ocean chemistry doesn't change uniformly over the entire planet — there are hot spots. No other studies along the Pacific coast have been monitoring acidity regularly, as this study did, so it's not clear how widespread the phenomenon is.
It's also not clear what we can do about it. Marine scientist Jane Lubchenco at Oregon State University says that even if the world abruptly shifts away from fossil fuels — and stops emitting billions of tons of carbon dioxide into the atmosphere every year — the oceans will continue to soak up carbon dioxide from the air and become more acidic.
Lubchenco says that means other ways must be found to help marine organisms survive this global threat. She recommends protecting marine life by reducing overfishing, cutting back on nutrient runoff, and creating marine reserves to protect the most valuable and vulnerable marine ecosystems. |
There are three real concerns here, which are of course tempered by the fact that there is very little information available about ocean acidity.
#1. The ten times faster than expected factor. Observed phenomena over and over again appear to occur faster than scientific models predicted.
#2. The fundamental bedrock of life the ocean represents. A mass extinction in the ocean would be very bad for us terrestrial organisms, depending on what dies. It could be as simple as no more sushi or reef diving to as bad as a drop in atmosphering oxygen concentration. Ouch.
#3. The fact that the atmosphere is the cause of this, that it mixes quite a lot, and it touches the entire surfact of the ocean. So this is only going to be regional in the context of what local geology might be buffering ocean acidity. |
-Chaloobi
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chaloobi
SFN Regular
1620 Posts |
Posted - 12/05/2008 : 12:05:14 [Permalink]
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Originally posted by Dr. Mabuse
Originally posted by chaloobi
Originally posted by Dr. Mabuse
When I look at CO2-graphs, it certainly seems to me like there is a measure of balance in the amount of CO2 in the atmosphere. |
If you look at the graphs of gas concentrations they got from the Greenland ice cores, CO2 and methane go up and down in ~120k year cycles in sync with the glaciation. It never stays constant over very long periods of time and has indeed never been constant through all of human history.
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Indeed. I'd like to emphasise "in sync with the glaciation". Depending on the over all state of the climate, methane and CO2 reach a level of equilibrium. Quantities remain fairly constant with regards to that particular time and climate, and the over all trend of the climate change. Not so today: levels are spiking unprecedentedly, way off the norm. |
No doubt it's a huge anomaly. There is a norm based on the current conditions, I'll give you that. But there isn't really an equilibrium or balance, just the illusion of such. Sorry to pick a nit but it was a big deal for me when I learned the concept of 'balance of nature' is entirely false. It's why I lost interest in conservation environmentalism. Creatures don't go extinct by accident, it's because they no longer fit their environment. And because the environment never stops changing, eventually everything goes extinct. And if human blundering causes enough changes, we'll cause our well-deserved own extinction. But life will go on. That's how I learned to stop worry and love the bomb, uh, global warming. |
-Chaloobi
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Simon
SFN Regular
USA
1992 Posts |
Posted - 12/05/2008 : 12:32:24 [Permalink]
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#1. The ten times faster than expected factor. Observed phenomena over and over again appear to occur faster than scientific models predicted.
#2. The fundamental bedrock of life the ocean represents. A mass extinction in the ocean would be very bad for us terrestrial organisms, depending on what dies. It could be as simple as no more sushi or reef diving to as bad as a drop in atmosphering oxygen concentration. Ouch.
#3. The fact that the atmosphere is the cause of this, that it mixes quite a lot, and it touches the entire surfact of the ocean. So this is only going to be regional in the context of what local geology might be buffering ocean acidity.
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Indeed, that is worrisome.
I found the original article on Pubmed, so I will read it and learn.
Thanks for pointing that out. |
Look again at that dot. That's here. That's home. That's us. On it everyone you love, everyone you know, everyone you ever heard of, every human being who ever was, lived out their lives. The aggregate of our joy and suffering, thousands of confident religions, ideologies, and economic doctrines, every hunter and forager, every hero and coward, every creator and destroyer of civilization, every king and peasant, every young couple in love, every mother and father, hopeful child, inventor and explorer, every teacher of morals, every corrupt politician, every "superstar," every "supreme leader," every saint and sinner in the history of our species lived there – on a mote of dust suspended in a sunbeam.
Carl Sagan - 1996 |
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Simon
SFN Regular
USA
1992 Posts |
Posted - 12/05/2008 : 13:25:04 [Permalink]
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Ok; I went over it.
First of all, the study mention a wide daily variation in pH which is typical of shallow waters. Indeed, I think their sampling point were located within the first few meters of depth.
Furthermore, Tatoosh Island appears to me granitic in its geology, in which case it would be more sensitive to variation in pH in more sedimentary areas.
My guess: these observations are worrisome, alarming even, but probably do not apply to most of the world's oceans. How much is the situation elsewhere better? Well, that anyone's guess and certainly this study justify additional investigations... |
Look again at that dot. That's here. That's home. That's us. On it everyone you love, everyone you know, everyone you ever heard of, every human being who ever was, lived out their lives. The aggregate of our joy and suffering, thousands of confident religions, ideologies, and economic doctrines, every hunter and forager, every hero and coward, every creator and destroyer of civilization, every king and peasant, every young couple in love, every mother and father, hopeful child, inventor and explorer, every teacher of morals, every corrupt politician, every "superstar," every "supreme leader," every saint and sinner in the history of our species lived there – on a mote of dust suspended in a sunbeam.
Carl Sagan - 1996 |
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chaloobi
SFN Regular
1620 Posts |
Posted - 12/06/2008 : 08:05:11 [Permalink]
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Originally posted by Simon
Ok; I went over it.
First of all, the study mention a wide daily variation in pH which is typical of shallow waters. Indeed, I think their sampling point were located within the first few meters of depth.
Furthermore, Tatoosh Island appears to me granitic in its geology, in which case it would be more sensitive to variation in pH in more sedimentary areas.
My guess: these observations are worrisome, alarming even, but probably do not apply to most of the world's oceans. How much is the situation elsewhere better? Well, that anyone's guess and certainly this study justify additional investigations...
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Yeah, it surprises me nobody's been monitoring ocean pH on a wider scale. |
-Chaloobi
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chaloobi
SFN Regular
1620 Posts |
Posted - 12/06/2008 : 08:18:18 [Permalink]
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Originally posted by Dude
chaloobi, the wiki article reflects what I had learned concerning the interglacial periods. Sorry I didn't throw in a reference or link to something! Busy week.
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Here's the research I was talking about:
Link: http://www.virginia.edu/topnews/releases2003/climate-dec-9-2003.html
HUMANS BEGAN ALTERING GLOBAL CLIMATE THOUSANDS OF YEARS AGO, STUDY SHOWS
December 9, 2003 -- A new hypothesis suggests that humans began altering greenhouse-gas concentrations and global climate thousands of years ago, long before the 1800s date widely assumed. In a paper to be presented at the December American Geophysical Union meeting in San Francisco and published in the December issue of Climatic Change, climate scientist Bill Ruddiman, professor emeritus of environmental sciences at the University of Virginia, concludes that human-caused emissions of carbon dioxide (CO2) since 8,000 years ago, and methane (CH4) since 5,000 years ago have combined to prevent a significant natural cooling of Earth's climate.
Cyclic changes in these two greenhouse gases and in the size of ice sheets have occurred over hundreds of thousands of years for natural reasons. These natural cycles are driven by small variations in Earth's orbit that cause rhythmic changes in the amount of solar radiation received at every location on the planet. The changes in solar radiation in turn cause predictable changes in climate that drive the greenhouse-gas cycles. But within the last several thousand years, these natural cycles were over-ridden by human activities that resulted from the early spread of agriculture in Eurasia, Ruddiman said.
Highlights of the new study include:
Beginning 8,000 years ago, humans reversed an expected decrease in CO2 by clearing forests in Europe, China, and India for croplands and pasture (page 2).
Beginning 5,000 years ago, humans reversed an expected decrease in methane by diverting water to irrigate rice and by tending large herds of livestock (page 3).
In the last few thousand years, the size of the climatic warming caused by these early greenhouse emissions may have grown large enough to prevent a glaciation that climate models predict should have begun in northeast Canada (page 4).
Abrupt reversals of the slow CO2 rise caused by deforestation correlate with bubonic plague and other pandemics near 200-600, 1300-1400 and 1500-1700 A.D. Historical records show that high mortality rates caused by plague led to massive abandonment of farms. Forest re-growth on the untended farms pulled CO2 out of the atmosphere and caused CO2 levels to fall. In time, the plagues abated, the farms were reoccupied, and the newly re-grown forests were cut, returning the CO2 to the atmosphere (page 5).
Humans Reversed the Natural Methane Trend 5,000 Years Ago
Natural controls on methane.
Bubbles of ancient air preserved in cores drilled from the Antarctic ice sheet show that atmospheric methane concentrations over the last 350,000 years varied at a cycle of 22,000 years. The reason for this rhythm is well understood. Changes in Earth's orbit at this cycle cause variations in summer solar radiation. When a stronger summer sun heats the land, hot air rises, and air flowing in from the ocean to replace the rising air carries moisture that falls in summer monsoons. The monsoon rains then fill up natural wetlands that emit methane. The result is a predictable 22,000-year methane cycle resulting from tropical monsoons driven by summer solar radiation.
Breakdown of Natural Controls.
Near 11,000 years ago, methane concentrations reached a natural maximum predicted by the most recent peak in summer solar radiation. The subsequent drop in methane |
-Chaloobi
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| Edited by - chaloobi on 12/06/2008 08:23:43 |
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Potential Solution for Global Warming?
