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Föld bolygó: a szeretett otthonunk A széndioxidtól a klímaváltozásig: In-depth with David Archer, PhD in Geophysics - 1.rész    1. rész
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 From CO2 to Climate Change: In-depth with Professor David Archer, PhD in Geophysics

Recently, more and more scientific research indicates that huge amounts of methane and other greenhouse gases stored in the ocean, permafrost and Arctic tundra are in danger of being released into the atmosphere due to global warming.

In order to learn more about this issue, Supreme Master Television recently interviewed Dr. David Archer who holds a PhD in Geophysics.  For the past 15 years, he has been a professor at the University of Chicago in Illinois, USA.  Professor Archer is an expert on the subject of the global carbon cycle and specializes in studying ocean sedimentary processes. He teaches classes on global warming, environmental chemistry, and global geochemical cycles.

Dr. Archer has also authored a book on climate changed entitled, Global Warming: Understanding the Forecast. He is in the process of working on another book entitled, From Here to Eternity: Global Warming in Geologic Time. On Planet Earth: Our Loving Home today, we present to you Dr. Archer’s interview with Supreme Master Television.


Supreme Master TV: I know that one area of your research  was in methane hydrates. Could you tell us what methane hydrate is and how it can become methane gas?

Dr. David Archer : Methane hydrate is a peculiar form of water ice where the water freezes into a cage like a soccer ball and the methane gas is inside the soccer ball, frozen and trapped in this ice, but if it becomes too warm, then this ice will melt and it can release the methane into the environment.

Supreme Master TV: What would trigger their release?

Dr. David Archer: Warming, from global warming, from rising CO2 concentrations. So carbon dioxide, CO2, is a greenhouse gas and it causes the surface of the earth to warm. This is very well understood. And eventually the warming at the surface can also make the deep ocean get warmer also. Now this takes a long time. If the methane from the hydrates were to escape and actually make it to the atmosphere methane is actually a much stronger greenhouse gas than carbon dioxide is, and so this could lead to stronger warming than we would get just from the carbon dioxide.

Supreme Master TV: How much methane do you think there is stored in the earth?

Dr. David Archer: It’s a huge amount, actually. They measure amounts of carbon in units of a billion metric tons and so there are maybe one hundred or several hundred billion metric tons of carbon as oil and maybe another couple hundred of methane in traditional natural gas reservoirs: If you cook on a stove with gas that comes from a gas well. The largest fossil fuel type is coal and there are maybe five thousand gigatons, a billion metric tons of coal So coal is the largest of the fossil fuel types. But of this methane hydrate in the ocean, there may also be thousands of billion metric tons.

So there’s enough carbon there that it could double the amount of carbon that could ultimately be released into the atmosphere. It’s a huge amount. There’s so much of it that if a fraction of it, say 10%, were somehow to get out into the atmosphere all at once, it would be the same as changing the CO2 concentration by a factor of ten.

Dr. David Archer: If you could just take the earth and give it a shake, the ice that holds the hydrate that holds the methane floats in the water. It’s held at the bottom of the ocean because there’s mud sitting on top of it. But if you just shook everything up,it would float up and so much methane would be released that the climate would completely melt down.

Supreme Master TV: Where would these stores of methane hydrates be located around the earth?

Dr. David Archer: They tend to be just offshore, around the edges of the oceans, so not too deep not out in the middle of the ocean, because there’s not enough methane there to make the hydrates and not too shallow because the pressure isn’t high enough to make the hydrate either. So it’s sort of in middle depths in a ring around the ocean. The Arctic Ocean has more than its share of methane hydrate because the water is colder there so that means that hydrate can be found at shallower depths in the Arctic because the colder water can stabilize the hydrates

So shallower in the ocean means that the warming from global warming can reach that faster than it can everywhere else in the ocean. Also there is thought to be more intense warming in the high latitudes. Alaska and Siberia, it’s warming up there much more than it is here in Chicago because that’s just the way the climate of the earth works, and so the Arctic is the place to be the most interested in methane hydrates and how they might affect the climate.

Supreme Master TV: Speaking of the Arctic, are there methane hydrates in the permafrost soil?

Dr. David Archer: Yes, there are thought to be some methane hydrates in the permafrost but more important in the permafrost is peat, which is frozen organic carbon, you know grass, roots, and things like that. They’ve been frozen for many years, tens of thousands of years but now when they thaw, they decompose and they produce methane and also carbon dioxide.

One way that this happens is in lakes in the tundra in the Arctic, so a lake covering the surface melts down some of the peat underneath it and so you get these methane bubbles that come out very strongly so it’s possible that with more warming could be more lakes and then more methane released into the atmosphere.

Today on Planet Earth: Our Loving Home we have Dr. David Archer, a professor of geophysical sciences from the University of Chicago to discuss with us about climate change.During the 2007 summer ice melt season in the Arctic, the accelerated pace of ice melts greatly alarmed polar researchers in the scientific community.

From 2006 to 2007, they had never witnessed such a drastic reduction in summer ice melt. Furthermore, the disintegration of Antarctica’s Wilkins ice shelf on February 28, 2008, where a huge 406 square kilometers of ice crumbled into the ocean, drew global attention and concern to the rate of climate change exceeding worst case scenarios made by the United Nations Intergovernmental Panel on Climate Change. Let’s now hear from Dr. Archer, who clearly defines the importance of the Arctic ice packs in stabilizing our climate.

Dr. David Archer: The sea ice plays a strong role in the climate of reflecting sunlight back out to space and so when you melt that sea ice, the sun shines in the Arctic year round, all 24 hours of the day in the summer time so it’s a lot of sunlight, and so you start absorbing that sunlight and that could change the climate of the Arctic very strongly and that could indirectly affect the methane. And also the Greenland ice sheet and the circulation of the North Atlantic and lots of other things in the high latitudes.

Supreme Master TV: I’m going to venture into asking you what is the concentration of carbon dioxide in the air right now and what was it before we noticed that there was global warming going on

Dr. David Archer: The concentration in the year 1750, nobody could measure concentrations then but we have bubbles of ancient air trapped in ice cores so we can measure, we can know that at that time before human activity, the concentration of carbon dioxide was about 280 part per million. So out of a million molecules of air, 280 of them were carbon dioxide.

 And today it is about 380 or 385, something like that. Before our period of warm climate in the last ice age, the CO2 concentration in the air was about 200, so going from 200 to 280 was enough to change the climate of the earth from the glacial world when there was two miles of ice over our heads here in Chicago to the interglacial world. So that was 200 to 280 and now we’ve gone all the way to 380. The ice core data that tells us about the value in 1750 or in the ice age now goes back 800,000 years and the CO2 concentration today is much higher than it’s ever been throughout that 800,000 year time period.

Supreme Master TV: So in the history of earth, We’ve had global warming before and we’ve recovered from it and we go into periods of glaciers and then we warm up again. Are we doing that? Do you think this is just another phase of the cycle?

Dr. David Archer: Well, in one sense you are right but in another sense you are using the word “we” and we as human beings have never endured climate changes such as the one that we are now causing before civilization and agriculture all these things happened in a time period of very, very stable climate called the Holocene of the last ten thousand years.

Before that was the glacial time, the glacial climate was much more turbulent and there were strong changes; just a few years the climate would change from one state to another and then back. But the time that civilized man has been in existence, the climate has been very stable and we’re now threatening to leave that stable climate, going into a climate such that we, as a species, have never even seen before.

Supreme Master TV: But this time rather than from volcanic eruptions emitting massive amounts of carbon dioxide, this is human induced, fossil fuel carbon dioxide accumulating.

Dr. David Archer:  That’s absolutely right. We can measure the amount of carbon dioxide in the atmosphere and compare that with how much fossil fuel we’re burning and it’s very clear that the carbon dioxide concentration is going up because of human activity, it’s not because of volcanoes or anything like that.
Supreme Master TV: But the consequence would be similar to what we’ve seen in the past. The earth would warm up in a similar way and have similar results.

Dr. David Archer: Yes, there was a climate event 55 million years ago called the Paleocene-Eocene Thermal Maximum event and it’s very unclear exactly what happened but there was some release of carbon dioxide from the earth into the atmosphere fairly quickly within somewhere between instantaneously and ten thousand years; they don’t really know how long it took but the amount of carbon that was released was comparable probably to the amount of coal that we have or the amount of methane hydrates.And then so the earth warmed and then it took 150,000 years for the climate to recover from that which is how long it will take actually for the earth to recover from global warming as well.

Carbon dioxide when you put in the air, it just accumulates in the atmosphere and ocean system and it takes a very long time for that to recover. The earth has mechanisms to stabilize its climate. It’s almost miraculous to imagine but it seems to be true but these mechanisms to stabilize the climate act very slowly; they take hundreds of thousands of years. And so we have it in our powers to change the climate of the earth for a very, very long time.

SUPREME MASTER TV: Is there a certain number a concentration level that once we reach we’ll see catastrophic events?

DR. DAVID ARCHER:  I personally think that we’ve already passed a danger limit. The sea ice in the Arctic Ocean in 2007 just crumbled. The amount of sea ice in the Arctic Ocean has been decreasing over the years but then in 2007 it just crumbled. And the earthquake activity and the acceleration of the flowing ice in Greenland, I think these are signs that we are already in dangerous territory. Another way to specify or to define, to try to answer your question is to say when we can predict that things are not just possibly dangerous but likely to be harmful.

It’s very difficult to predict but people oftentimes define a dangerous temperature change as 2C warming over the natural level. So far the earth has warmed about 0.7C and even if the CO2 concentration in the air were to stop rising today and just stay at 380 forever, the temperature of the earth would continue to rise to about 1C. If we want to avoid warming more than 2C, we have to freeze the emission of carbon dioxide so industry has to stop growing.

Right now its growth is projected to be twice as fast, twice as much carbon dioxide emitted per year in 50 years as it is now. We need to freeze that and not let it grow, and then in the next couple of decades it has to start going down or else we will exceed a dangerous temperature change of 2C.

2C would be warmer than the earth has been in millions of years, so to try to predict where you would have droughts or whether hurricanes would get much more intense than they are today or whether sea levels could rise by tens of meters, it’s very difficult to make those kinds of predictions because that would be warmer than the earth has been in so long. 

SUPREME MASTER TV: Would you say that there’s a certain point of no return if we warmed a certain number of degrees?

DR. DAVID ARCHER:  Yes, I think there probably would be a point where the large ice sheets such as the Greenland ice sheet or the west Antarctic ice sheet would start to flow into the ocean and melt, raising the sea level. And it may already be starting; it’s possible. They can see acceleration of the ice, flowing faster than it used to, and they can hear earthquakes in the ice indicating that the ice is flowing faster than it used to. So if the ice sheets start to flow more quickly, that might be a point of no return.

SUPREME MASTER TV: What would the world look like, do you think, if we were to reach that point?

DR. DAVID ARCHER:  Well, There have been times in the past like you mentioned before when CO2 concentrations were much higher than today and when there was basically no ice on the planet. So the sea level in such a hothouse world would be about 70 meters higher than today so if you just looked at a map of the earth, it would look different. Florida would be gone, for example, many of the river deltas would flood in such a situation.

 It’s called a hothouse world; in a hothouse world there’s much less temperature difference between the equator and the poles so it’s basically almost tropical all the way to the poles. There are alligator teeth, crocodile teeth that they find, fossils in Siberia and in Alaska from these hothouse kinds of worlds. Crocodiles can’t live if it ever gets below freezing so that would be a world that would be tropical all the way to the poles.

But the details of how that climate could work or how many people it could support are difficult to predict, and what’s even harder to predict, actually, is the transition from our relatively cool world to such a world. The forests would all be in the wrong places, so do they just die or do new trees grow in to sort of keep up with the changes in climate? It’s very difficult to prepare for how society could cope with a transition like that.

SUPREME MASTER TV: It does seem like the problem of global warming is pointing us in a new direction where we would have to cooperate more, nations would have to be benevolent towards each other. (Yes) And even individuals would need a change in lifestyle, hopefully for the better.

DR. DAVID ARCHER:  I think that’s true, although I think they could change the energy infrastructure so that when you plug something into the wall it comes from a carbon-free energy source. I mean individual virtue is a powerful thing in terms of changing energy use but it’s not going to be enough.

We have to stop building these coal-fired power plants or else all is lost. I feel that the United States should take the lead in making these kinds of changes. And I also feel that we have the resources that we can begin to develop alternative energy technology and then make that available to the rest of the world.

SUPREME MASTER TV: So you would say to the leaders of the government and the policy makers that the time to act is now?

DR. DAVID ARCHER:  Yes. The last I heard there were 160 new coal-fired power plants that are being planned or designed or built in the U.S. alone and in China they are building a new coal-fired power plant every week and if they build all those things then all is lost. Those power plants are a crime against humanity is what I would tell the leaders.

SUPREME MASTER TV: Will we see like solar energy or hydrogen energy so that it’s green, so that we have energy that does not generate greenhouse gases at all?

DR. DAVID ARCHER:  Yes. That would be much better. Hydrogen isn’t a source of energy; it’s more like a way of storing energy. We have to make hydrogen, so maybe you could use solar cells to split water to make hydrogen and then use hydrogen in a car or whatever, but there’s no place to sort of mine hydrogen exactly so it’s not a primary energy source.

But there’s lots of sunlight; there’s a thousand times more sunlight that hits the earth every day than we actually use in all of our energy production, so if we can start harvesting that efficiently that would solve all of our needs. I’ve read that to supply the United States would require covering about 2% of the land area of the United States, which is about how much area is covered by roads. So it sounds like a lot but if you told somebody a hundred years ago that 2% of the land would be covered by roads they would say that that was a lot too. They would probably say that it was impossible.

SUPREME MASTER TV: Do you stay up nights worrying about global warming?

DR. DAVID ARCHER:  Yes, sometimes I do. I feel like we have the technology to avoid global warming. We know of alternative ways of extracting energy from coal, for example, and we’re starting to learn how to build windmills and solar cells and develop energy efficiency. So I don’t think it’s impossible to avoid. I think technologically we know how to do it but this is a more difficult social problem than humankind has ever faced before because it requires global cooperation.

SUPREME MASTER TV: There are two other University of Chicago researchers who have shown that adopting a vegetarian diet is one of the most effective ways to reduce greenhouse gas emissions. Do you have any comments on their research?

DR. DAVID ARCHER:  They looked at this very carefully. It’s very clear that when you grow grain and then feed it to animals and then eat the animals, you lose 90% of the energy from the original grain, and so not only can you feed fewer people on the agriculture that you have but as they discovered, it also requires a lot more fossil-fuel energy to make that happen. It makes that much difference to the CO2 emissions.

Along with the United Nation’s report and many other scientists’ observations, it is clear that adopting a vegetarian diet would be one of the most effective actions an individual can take to help reduce the effects of global warming.We sincerely thank, Dr. David Archer, for your invaluable research in the science of geophysics in providing us with further information on our Earth and the effects of climate change.
 

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