For a long time, the climate science consensus suggested that to avoid increased average surface temperatures beyond those to which our civilization could adapt, we need to reduce emissions 80 percent by 2050. (No one suggested we stop there, but that goal was advocated as a way to avoid tipping points.)
There were voices from the beginning arguing that this was too slow a phase-out. But as Joe Romm has argued, the consensus-seeking nature of the IPCC process tends to downplay and ignore real dangers. It has become obvious that we need to reduce emissions faster than the conventional wisdom of a few years ago suggested.
For example, the rate at which the oceans absorb CO2 has slowed drastically as they become saturated. This suggests another tipping point looms: when the oceans begin to release the CO2 they contain, they’ll become a source rather than a sink. At any rate, if the ability of nature to absorb our emissions has dropped, we have to cut emissions more than we would have.
Similarly, the ice caps are melting at a much faster rate than mainstream predictions suggested. Because water reflects less heat than ice, this is another cooling mechanism that has been reduced. Again, we have to cut those emissions faster than we planned.
How fast do we need to cut emissions?
One obvious answer is, “as quickly as possible,” but that is not really an answer. “Possible” is a political calculation, not just a physical, technological, or economic one. “Failure is not an option” is unfortunately an empty boast. Failure is always an option. People die every minute because failure is an option. I’m sure whoever cut down the last tree on Easter Island had some rationalization. I have a dear personal friend who has all sorts of lung problems, gets pneumonia regularly, and still has not quit smoking, in spite of many attempts. I hope she manages to quit before it kills her, but it looks to me like failure is definitely an option.
What we want with emissions cuts is the best of chance of survival. We must consider the probability that a certain reduction rate will avoid the worst consequences of unchecked climate chaos, and that it will preserve our technological civilization and our ability to continue to grow enough food for everyone.
We must also consider the chances of winning politically. Reducing emissions so slowly that we get caught in feedbacks, which nullify the first cuts, is pointless. Calling for cuts that are so fast we have zero chance of politically attaining them is also pointless. Within that range, we have to weigh how much winning a cut politically improves the probability of survival against how much calling for a certain rate of reduction lowers the chance it will be enacted.
And no, rate of reduction is not the only thing that determines chances of enactment. There is much more to political success than choosing a policy sweet spot. But a really bad policy choice does ensure failure.
We also have to consider that when it comes to emission cuts, “objects in this mirror are larger than they appear.” Consider the 80 percent emissions cut by 2050 that now appears inadequate. Population by 2050 is expected to be about 50 percent higher than at present, so this would require much larger per-capita reductions. Unless we end up with a decades-long depression (certainly possible), we can expect worldwide economic growth per-capita. An 80 percent absolute reduction by 2050 probably requires an 80 percent reduction per unit of GDP by 2030 or 2040.
Let’s look at what the scientific community says about timing. James Hansen, perhaps the world’s leading climate scientist, has suggested we need to cut not just emissions but also atmospheric concentrations down to the equivalent of 350 parts per million of CO2 (PDF). This is below current concentrations of 385 parts per million, and thus would require negative emissions. To lower concentrations back to 350 parts per million, we have to peak soon and start dropping emissions by around 2015. Because Hansen does not say how quickly we must drop down to 350 ppm, we can’t infer the other end of the schedule from this, but obviously it means faster reductions than most standard IPCC reduction scenarios.
The climate modeling group of the School of Earth and Ocean Sciences of the University of Victoria in Canada suggests that we need net emissions of zero by 2050 (PDF). (To be exact, they suggest a cumulative emissions limit that would imply this. Some of their statements quoted in the popular press suggest that this would be 90 percent met by actual reductions, and 10 percent met by sequestration.) Their calculations suggest that even this reduction would still have a 33 percent chance of a temperature rise above 2°Celsius, which is often considered the “safe threshold” level. And many question whether even 2°Celsius is safe.
If we want a better than a 66 percejt chance of survival, and we want to stay well below 2° rather than barely below 2°, it looks like we need to cut even faster. Monbiot’s Heat suggested a 90 percent reduction over 20 years. I’ve proposed a 95 percent reduction over the same time frame. If you turn back to the University of Victoria document (PDF), and turn to the graph “Probability of exceeding 2°C,” you will see that these proposals fit nicely into the space on the bottom left of the graph, which is much safer than 2°.
I have argued in the past that we could reach this target with an increase in GDP from energy and maintenance savings and from various positive externalities (other than reduced climate chaos).
Lester Brown suggests an 80 percent reduction over the course of 10 years (PDF). If we look at the graph again, this suggestion doesn’t add a great deal of safety, given the cost. Maybe Brown is using a different graph. He leaps from Hansen’s ultimate target of a 350-ppm concentration, with no end date specified, to espouse “cut 80 percent by 2020,” without any middle steps that explains why he chose 2020, rather than 2015 or 2030.
Still, an 80 percent reduction in emission rates by 2050 no longer appears adequate. To a lot of people it never did. But even those who supported that rate of reduction before have to admit that with feedbacks occurring much faster than predicted, we have to escalate the rate of reduction. We can argue about how much faster, but that we have to cut significantly faster seems difficult to dispute.
At this point I don’t think there is any doubt we need to be most of the way to zero by 2030. (Brown would say by 2020.) Maybe even more importantly, emissions have to peak and begin to drop by 2015, which means we have to start physically making changes by 2012 at latest, but better this year. If they continue to rise through 2020 as some advocate, the drop back to 350 ppm becomes almost impossible.
We are out of time. We need to move from dirty to clean tech. And if we choose to make that transition, then: “Yes, we can.”
‘Copenhagen Diagnosis’ offers a grim update to the IPCC’s climate science
Comments
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Colin Wright Posted 1:05 pm
25 Jan 2009
By the way, David Spratt argues that 350 is still too high (by century's end)! He thinks 300 ppm is the limit needed to restore Arctic sea ice, and thus stabilize the Greenland ice sheet:Hansen explains in the same article that 350ppm is a precautionary target to stop global loss of ice-sheets, because the paleoclimate record shows 450ppm ± 100ppm as boundary for glaciation/ deglaciation of Antarctica...Stabilization of Arctic sea ice cover requires, to first approximation, restoration of planetary energy balance... A further imbalance reduction, and thus CO2 ~300-325 ppm, may be needed to restore sea ice to its area of 25 years ago.
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LPS Posted 1:36 pm
25 Jan 2009
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Gar Lipow Posted 2:17 pm
25 Jan 2009
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amazingdrx Posted 4:30 pm
25 Jan 2009
I think lester is referencing that feature of the situation in his call for quicker action. In fact he is being reasonable. Conventional wisdom that we have time to waste is a fantasy.
A gradual reduction of around 6% per year from conservation and conversion to renewables would be quick enough, but only if we start right away. Any delay at the start lets the exponential positive feedback effects get ahead.
Slow and steady will win. So far even that slow pace of 6% per year is too fast for conventional wisdom.
http://amazngdrx.blogharbor.com/blog John Schneider, Northern Wisconsin
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Billhook Posted 6:06 pm
25 Jan 2009
Under the rule-of-70, a 6% exponent would give less than two halvings in that 21 years, i.e. around a 70% cut.
By contrast, a more stringent 9%/pa cut would achieve 75% by 2025, which looks more appropriate, but very severe in its impacts on energy usage in particular, thus
a. predictably cutting economic activity, and
b/. arousing vocal opposition.
However, a simple exponent is far from the optimal rate of change, which would in fact be a sigmoid curve (S-bend) starting slowly before accelerating towards a steepest rate of change as we pass zero net emmissions, (by 2030 ?) and then decelerating as we advance net carbon recovery towards say 265 ppmv CO2-eq. airborne concentration.
These numbers are of course only illustrative, but they may help to impress the point that an effective UN treaty is pre-requisite: it will engage the common interest and effort of the nations, and cannot be replaced (as Hansen proposes) by a mere coercive lever by which the West seeks to force developing nations' compliance.
In the long term, which this issue embodies, global co-operation is plainly our only recourse, meaning that the West's first duty is to acknowledge the equity of a transition to per capita parity of national emissions entitlements.
From this starting point the transfer of funds (for traded entitlement) ring-fenced to recipients' mitigation options, becomes relatively simple and routine.
Under the global economic stresses now foreseeable, it is crucial that this essential transfer of funds reflects the transparently equitable dynamic of Convergence.
Anything less would lack durability.
Regards,
Billhook
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Jon Rynn Posted 11:51 pm
25 Jan 2009
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amazingdrx Posted 12:15 am
26 Jan 2009
Denial for whatever reasons, economic or political are based on irrational conventional wisdom.
How could spending 1/3 of GDP have seemed even possible, much less reasonable, during WW II? And yet it finally ended the great depression.
Is it reasonable to invest in a green revolution to end climate disaster and economic recession/depression? Or is the conventional wisdom that it will take care itself the rational course.
History tells us to act now and avoid 10 or more years of economic and climate disaster.
Stimulus on top of the inflation from huge deficits and global financial ponzi schemes like "derivatives" and "credit default swaps" and the like have brought about, will cause more devaluation of our currency. That's a risk we have to take now.
But we need to recognize that risk by considering the disasters caused by rampant printing of money in the past. Post WW I Germany and the Russian Ruble are prime examples where inflation and currency devaluation bit back.
Investing the electronic printing press money in sound, productive green energy re-evolution will cut inflation to counter that natural inflationary trend. Why? Because energy cost inflation is at the heart of all inflation. It is multiplied through every step of marketing from wholesale to retail.
http://amazngdrx.blogharbor.com/blog John Schneider, Northern Wisconsin
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Ted Nace Posted 2:41 am
26 Jan 2009
So the economy will move toward electricity, and our job is to get the coal fleet phased out and make sure that the electricity is supplied by solar and wind. Fortunately, the public has far more leverage over coal than over oil, because so much of the remaining coal supplies are in federal hands. With Eastern sources of coal running out or being reined in by more aggressive mining standards, Western coal will become even more crucial. If the public chooses, it can accomplish everything through the lease price of this coal that could have been accomplished through carbon taxes or cap-and-trade. Even more direct control is possible, say by limiting leases or stopping them altogether. (Alternatively, aging coal plants could be shut down via a rising carbon output threshhold.) To replace the electricity these coal plants would have produced, government can use any of a range of policy options, starting of course with aggressive efficiency measures and continuing on with the vigorous ramping up of utility wind and solar electricity supplemented perhaps with federal solar/wind authorities. Obviously, wind and solar capacity can't be ramped up from 0 to 60 overnight, but the ramp-up can be relatively rapid and once the manufacturing facilities are built it can proceed at a high speed more or less indefinitely. By 2020, it's not pie-in-the sky to think that 30-50 GW of wind and 30-50 GW of solar could be built and installed annually. Siting issues are much less gnarly for wind/solar than for big central station fossil or nuclear facilities. Lead times are quicker. Once a solar thermal location is established at, say, the 400 MW size, it can simply grow outward to 600 MW, 1000 MW, what have you.
Thinking in terms of overall carbon reductions by a certain date, whether they be "80% by 2050" or whatever, is problematic because it obscures the huge differences between the two sides of the issue, oil/gas on the one hand, and coal/wind/solar on the other.
Instead of these percentage/date targets, it's better to think of how much of the carbon-in-the-ground we can afford to free into the atmosphere. I highly recommend the Kharecha/Hansen paper "Implications of 'peak oil' for atmospheric CO2 and climate," which does a great job of laying out this way of thinking about the problem, and clarifying the pace of a coal phase-out that will be needed to minimize the length of time the world stays in the greenhouse danger zone.
Help build CoalSwarm -- a shared informational resource on coal and alternatives to coal.
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Gar Lipow Posted 3:32 am
26 Jan 2009
A carbon atom is a carbon atom is a carbon atom. It assumes that remaining oil and gas supplies are low enough that a quick coal phaseout is sufficient.
One of things Hansen has said that in addition to a quick phaseout of coal, we have to avoid much additional use of unconventional oil sources - such as the Canadian tar sands.
Maybe x% by y is not how to draw legislation. (Though I will note a lot of legislators seems to think otherwise.) But it certainly is the goal. (If you prefer, you can specify total tonnes of human emission we can get away with adding to the atmosphere before we have to go emission negative and start being net sequestorers of greenhouse gases. Coal is certainly the worst of the fossil fuels. There are certainly good arguments for making it a focus for the majority of efforts. But eliminating coal is a means, not an end. And I don't think anyone thinks it sufficient. I'm not certain eliminating coal and unconventional oil is sufficient even for fossil fuel goals over the next 20 years. But assuming for the sake of discussions this is a sufficient goal when it come to fossil fuel still leaves us with the fact that we have to stop deforestation, convert agriculture from a carbon source to at least a modest (and perhaps moderate) carbon sink. We have greatly reduce methan emissions from mining, landfills, sewage, meat production and other forms of waste. We have reduce emissions from cement manufacture, chemical manufacturing, fabric manufacturing, and the manufacture of coolants.
The above is true or false, depending on how fast you need to cut emissions. So I don't see how that is an "obscuring" way to see the problem. You don't want to stop there, but I don't see how you can avoid starting there.
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Jon Rynn Posted 4:50 am
26 Jan 2009
By the way, if we eliminated all energy-related GHGs from fossil fuels we're talking about 56%, so that's not nearly enough to get to 80%.
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Pompey Road Posted 5:25 am
26 Jan 2009
The eons of time and nature was good to us down here. It was not until we become civilized that destroying our habitat become fathomable or fashionable.
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Karen Street Posted 5:25 am
26 Jan 2009
I want to remind people that there is no analysis accepted by IPCC that shows us getting to an 80% reduction in GHG emissions by 2050, even the IEA Energy Technology Perspectives that requires an unprecedented level of cooperation and remaking the world's economic system. Yet people on gristmill argue against some of the larger solutions.
We need major tests of carbon capture and storage, and we need nuclear power. We need solutions beyond what the policy community has found. They can be technological, perhaps more rapid change than anticipated. They can be policy.
Re Hansen and what he emphasizes, people who fly and drive tend to put disproportionate emphasis on coal. And it is true that solutions to coal might be easier to find than solutions to oil. And it is true that it might be possible to burn all the world's oil and still keep temperature increase below 2 C, but it is not possible if we burn all the world's coal.
An 80% reduction by 2050 means that per capita emissions are 3 - 4% of current US emissions.
To the to-do list, I would add, get the world's (and US) attention. This requires finding ways to take the discussion to people who are not receiving it. I thought the election would make a difference, but the public seems to have glided over the fact that Obama and McCain kept raising climate change as an issue they agreed was necessary to address rapidly.
Karen Street
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Gar Lipow Posted 6:38 am
26 Jan 2009
That is exactly right. We have to tackle the different forms of land use, cement, F5, industrial chemicals, space heating. And the reason IPCC never comes close in its scenarios is that it assumes price as the main driver. So much per tonne for emissions produces so and so an emissions reductions. And no price they consider gets you there. That is not an argument that reductions are not achievable. It is an argument that price is not the right driver
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Jon Rynn Posted 6:53 am
26 Jan 2009
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Jon Rynn Posted 6:59 am
26 Jan 2009
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Jon Rynn Posted 7:03 am
26 Jan 2009
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amazingdrx Posted 8:47 am
26 Jan 2009
That assumption gets more and more dangerous as the GHG concentration travels up the curve.
I wish I knew how to put up a picture of the point I'm trying to make. Back to school, for the whole culture.
How do you get a math hating media full of english/journalism majors to embrace this public warning canmpaign? Even the science oriented seem to have trouble with these simple math principles.
Consult wiki's explanation?
http://en.wikipedia.org/wiki/Exponential_growth
http://amazngdrx.blogharbor.com/blog John Schneider, Northern Wisconsin
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Gar Lipow Posted 8:56 am
26 Jan 2009
Census International Data Base:
http://www.census.gov/ipc/www/idb/worldpop.html
Midyear pop 2010:6,869,643,038
Midyear pop 2030:8,378,629,430
That is about a tiny bit under a 22% population growth. So take absolute reduction of 80% in 20 years, and increase that by population increase and you end up needing a bit under a 96% emission decrease per person. If the decrease in 20 years is to be 90% in absolute terms, it comes so close to 100% per capita as for the tiny remaining emission not to be worth considering. And that is before we consider per capita economic growth above zero. So essentially we need to cut emissions over 20 years by between 95% per person and essentially zero.
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Jon Rynn Posted 9:58 am
26 Jan 2009
In fact, I think the best available example nowadays is tthe albedo positive feedback effect of the arctic ice melt leading to more arctic ice melt. So the positive feedback in climate change is actually the best known example in the public mind.
Not that I'm bitter.
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hapa Posted 10:36 am
26 Jan 2009
all the conventional oil.
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Karen Street Posted 10:36 am
26 Jan 2009
If population goes up 20%, then each person gets 100/120 of the allotment, which was 20%, so we still get 16.7%. However, we in the US emit way more than our share, so the average person will end up with 3 - 4% of US share. That means we cut way back, or we ask Cambodians to cut by the same percentage.
You're right it's carbon, not carbon dioxide. It doesn't work to say that some of it will be absorbed, because the amount absorbed is the maximum amount the Earth can absorb. At this time, this does not increase with the amount of emissions.
If no positive feedback.
And there is no group acceptable to IPCC that has found a path that gets us there from here.
Karen Street
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Karen Street Posted 10:39 am
26 Jan 2009
IPCC 2007 includes better estimates about positive feedback. I've heard several lectures on the subject and read several articles.
We don't know average positive feedback per ppm because that depends a lot on how many more ppm we intend to add.
Karen Street
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Gar Lipow Posted 12:37 pm
26 Jan 2009
"You're right it's carbon, not carbon dioxide." Actually CO2 equivalent. Greenhouse gases other than carbon containing ones are not trivial - SF6 and other F5 gases. (SF6 is 22,000 times as powerful a greenhouse gas as CO2). Also black carbon is much more powerful the CO2 as is Methane (natural gas/landfill gas/sewage gas) all CH4 is also many times more powerful. CO2 equivalent is a nice measure that converts them all to a common factor. Though actually these conversions are not as simple as we treat them as being. That is there are certain judgements made in saying that SF6 is 22,000 times more powerful than CO2. How we value strength of forcing vs. lifetime in atmosphere.
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Jon Rynn Posted 1:04 pm
26 Jan 2009
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Pangolin Posted 7:21 pm
26 Jan 2009
Assuming a dead stop on anthropogenic emissions of GHGs existing excess CO2 will force heating and massive methane releases as far as I know. The frozen biomass in the Arctic tundra exceeds all fossil fuels burned to date according to estimates I've read. If it thaws a significant fraction of this organic carbon converts to methane.
Is there some sort of methane consuming bacteria, epiphyte, fungi or lichen whose growth we can promote to pull this crucial gas out of the atmosphere?
Does anybody have any answers for these questions or is the IPCC officially head-in-the-sand on methane forcing? I'm feeling that simply getting to zero is not enough.
Put the Carbon Back
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dobermanmacleod Posted 8:00 pm
26 Jan 2009
"Ultimately, responding to global warming is a political issue." --Lorrie Goldstein, Sun, 16 March 2008
"I know of no realistic person who thinks carbon dioxide emissions are going to do anything but grow. Most European countries are not meeting their emissions goals, and of the ones that have, it's because their economies are collapsing. In the United States, this notion that we're going to reduce our emissions by 80 percent is pure fantasy." --Pete Geddes, Foundation for Research on Economics and the Environment, 2 April 2008
"By the year 2050, the Census Bureau projects that our population will be around 420 million. This means per capita emissions will have to fall to about 2.5 tons in order to meet the goal of 80% reduction. It is likely that U.S. per capita emissions were never that low - even back in colonial days when the only fuel we burned was wood. " --"The Real Cost of Tackling Climate Change," WSJ
Furthermore, any carbon diet strategy would be dependent upon clean coal:
"The vast majority of new power stations in China and India will be coal-fired; not "may be coal-fired"; will be. So developing carbon capture and storage technology is not optional, it is literally of the essence." --"Breaking the Climate Deadlock," Tony Blair, June 26, 2008
But, Vaclav Smil, an energy expert at the University of Manitoba, has estimated that capturing and burying just 10 percent of the carbon dioxide emitted over a year from coal-fire plants at current rates would require moving volumes of compressed carbon dioxide greater than the total annual flow of oil worldwide -- a massive undertaking requiring decades and trillions of dollars. "Beware of the scale," he stressed."
In other words, it is doubtful that even the unrealistic cuts US President Obama committed to support in the campaign will significantly slow global warming.
"What I learned in the past few years is that politicians often adopt convenient policies that can be shown to be inconsistent with long-term success, given readily available scientific data and empirical information on policy impacts." --Dr Jim Hansen, NASA
"I'm going to tell you something I probably shouldn't: we may not be able to stop global warming. We need to begin curbing global greenhouse emissions right now, but more than a decade after the signing of the Kyoto Protocol, the world has utterly failed to do so. Unless the geopolitics of global warming change soon, the Hail Mary pass of geoengineering might become our best shot." --Bryan Walsh, Time Magazine, 17 March 2008
"The alternative (to geoengineering) is the acceptance of a massive natural cull of humanity and a return to an Earth that freely regulates itself but in the hot state." --Dr James Lovelock, August 2008
For instance, there is a simple and cheap way to cool the Earth immediately: just add a little sun dimming aerosol into the upper atmosphere:
"The Panel (on Policy Implications of Greenhouse Warming) calculated that adding stratospheric aerosol dust to the stratosphere would cost just pennies per ton of CO2 mitigated." --"The Incredible Economics of Geoengineering"
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Jon Rynn Posted 12:49 am
27 Jan 2009
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Jon Rynn Posted 12:51 am
27 Jan 2009
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amazingdrx Posted 1:31 am
27 Jan 2009
I think that's true, but it's hard to tell since methane and ice melt positive feedback haven't been integrated into warming models. It might already be too late to head off run away GHG disaster with zero GHG emissions.
A switch to organic waste (garbage, manure, crop waste,forest waste, weed and algae overgrowth, sewage)biogas/organic fertilizer and desalination of seawater to green deserts might provide enough extra sequestration to turn the situation around. Food and methane energy production even provides a profit motive for these activities.
Nations in the ME, like Saudi Arabia, who have extra cash due to oil, have and incentive to invest in these technologies. Once mass production of the devices necessary takes hold, they can be used to convert all agriculture to organic fertilizer and green enough desert area to reverse climate disaster.
What is the sequestration potential of soil? In the Minnesota prairie ecosystem it was measured to be 1.8 tons of CO2 per acre per year.
With GHG emissions at zero, how much land under organic fertilizer based ag and conservation land would it take to reverse GHG trends? is it possible?
How many acres of potential soil carbon sink are out there that could be greened in the deserts and rehabilitated in chemical ag croplands? And how fast could this proceed if it is started up simulataneously along with renewable energy and energy conservation efforts?
The thing that makes it possible to overtake GHG disaster is the same phenomenon that is propelling it. Exponential growth. An energy/ag re-evolution can proceed exponentially too. That's how products, like the automobile for instance, took over from the horse and buggy.
49 gigatons CO2 equivalent is causing our problems, if I remember the figure Jon quoted correctly. If that went to zero over 10 or 15 years and if organic ag and desert greening was able to ramp up to soak up 10 gigatons per year on that same time scale, where would the crucial GHG ppm be?
http://amazngdrx.blogharbor.com/blog John Schneider, Northern Wisconsin
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amazingdrx Posted 1:53 am
27 Jan 2009
To visulize it: That would take 10 areas of land each 1000 by 1000 miles (or the equivalent) of desert greened and/or agricultural land converted to organic fertilizer or conservation land.
That is without the total benefit of eliminating nitrous oxide from chemical fertilizer (at 296x the GHG effect of CO2 equal to 2/3 of the CO2 sequestration of the crop fertilized), eliminating the methane release from stray waste stream products like manure and sewage and fertilizer run off, and the reflective cooling effect of desert cloud formation.
Maybe another 5 gigaton elimination effect could be added to account for this?
Please check my calculations! I am probably wrong, hehey.
Is it possible to add an area equivalent to 1000 miles on a side to desert greening and organicically fertilized cropland per year? Starting at near zero and ramping up to meet the 10 million square mile level over 10 to 15 years?
http://amazngdrx.blogharbor.com/blog John Schneider, Northern Wisconsin
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Jon Rynn Posted 1:55 am
27 Jan 2009
oy vay, so of course I'll try a back of the envelope: according to wikipedia, the land surface of the earth is 148,940,000 km2. 1/3 of that is desert; although apparently there's desert and then there's desert, but say 1/3 of that is 50,000,000 km2. there are 2.6 square km in a mile, so about 20 million square miles, times 640 acres, about 12 billion acres in the desert?
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amazingdrx Posted 2:31 am
27 Jan 2009
I'm thinking of large floating wind/wave powered pumps to do the desalination with low pressure evaporation (vacuum pumping in the seawater chamber) and a heat pump to recycle the heat collecting in the condensor. But concentrating solar could provide extra heat as well.
The idea of pumping the seawater up onto shore and having long pipelines with a solar concentrating system all alomg the pipe might fit well with your idea of onshore desalination.
The pipelines are needed anyway, so why not use them as solar energy collector/desalination vessels? Vacuum could lower the boiling point and the water vapor could be tapped from the pipeline and condensed at the point of use on the desert farming area, with extra high salinity water returned to the ocean.
The high salinity water could return condensation heat to the incoming seawater as it flowed back to the sea. With molten salt heat storage this could power desalination even after the sun sets.
http://amazngdrx.blogharbor.com/blog John Schneider, Northern Wisconsin
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Gar Lipow Posted 2:44 am
27 Jan 2009
So we really have to come pretty damn close to zero and do sequestration via agriculture and forestry. And we still may have to do artificial energy negative photosynthesis (that is use wind electricity or whatever cheap low carbon form of electricity we can come up with to remove carbon from atomosphere. Good part of that is that storage is not an issue, whatever we can get cheaply, soundly and sustainably. Variable or even intermittent is fine. But the immediate priority is low or zero emissions, plus modest sequestration from agriculture and forestry - 17% of current emmissios per year or less. (Brown says 17%, but he is not taking into account certain carbon losses in both low/no-till farming, and in biochar. So I think it is more like 10% of current human emissions annually. )
So fundamentally: decrease emissions by increasing efficiency and substituting renewable for fossil fuels. Decrese emissions by using the small amount of biofuels we can use sustainably. Decrease emissions by reducing non-fossil fuel emissions from industry, and from waste. Decrease emissions by switching to sustainable agriculture and forestry, and other land use. Increase sequestration via sustainable agriculture forestry, and some reforestation. Net what that can do is get us to zero, or perhaps 5% negative emissions. And even this I think will take 30 years not 20. But I think we can get to 95% fewer net emissions in 20 years. And so we do need to learn how to to artificial energy consuming removal quickly as possible, to be driven by wind or (though I doubt it) nuclear power. Note so-called carbon negative burning of biofuels won't do it. Because if you use biofuels past a certain point they have as many emissions as fossil fuels, and which point removing carbon from them is just like burning fossil fuel and removing carbon from it.
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amazingdrx Posted 3:18 am
27 Jan 2009
Renewably powered desalination and desert greening of an extra 3.3 billon acres of desert over 10 to 15 years, is that possible? 300 millon acres of newly green desert per year average over a decade. How mant acres of land are cleared for agriculture now? In places like Brazil, with 20 tractors proceeding down huge fields simultaneously? That must be the fastest ag growth we now see.
And where would it put the GHG ppm level at? If the sequestration rate could be boosted to 20% of that present 49 gigaton level.
Would it be enough to keep the ice caps, glaciers, tundra, and undersea methane ice from melting? And actually reverse the trend to increase ice formation year after year?
http://amazngdrx.blogharbor.com/blog John Schneider, Northern Wisconsin
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Jon Rynn Posted 3:43 am
27 Jan 2009
Also, we should reforest the tropics, which traps carbon in the soil (plus the trees). I'm not sure how much acreage that is.
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Gar Lipow Posted 4:04 am
27 Jan 2009
Basically we need to get PPM back to 350 (or maybe 300) by end of century according to Hansen. So we lower emissions by 95% by 2030, and to negative 5% by say 2040, then we have sixty years to go from 420 ppm to 350 ppm. (If we need to lower all the way back to 285, that can be done in the following century.) Negative 5% of current emissions won't do that, and I suspect that 20% won't either. We need energy negative concentrated removal of CO2 from that atmosphere that is fairly economical given cheap electricity. Note that "clean coal" technology won't do it. Carbon removal technologies needed to make burn fossil fuels in a "low carbon" manner require concentrated sources. Carbon removal from the normal atmosphere is a very different technology.
One way around this is to burn "carbon neutral" biofuel and then remove the carbon from that. The problem there is that only as a very small percent of energy can biofuel be carbon neutral or low carbon before such removal. After you use it past 11% of our current energy consumption (at most, and I think this is way too high that the real number is more like 7%)you start competing with natural ecosystems that remove as much carbon, or displace food production which will move and in turn displace such natural ecosystems.
So bottom line. We need to get 95% reduction over the next 20, years, and down to true net zero or even negavive 5% by 2040 or 2050. And then we need to figure out how to draw carbon directly from the atomosphere, probably with technology that is only in the demonstration phase today. There are actually things running on rooftops that draw carbon. I don't think they are advanced enough to be called protypes, at least not commerical prototypes. But they do run outside the lab so they are not just lab pheonomenas. What do you call a prototype that is past the lab stage,but still at the "possible but not feasible" stage?
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amazingdrx Posted 4:11 am
27 Jan 2009
Prairie soil builds up just like peat. Sequestering more carbon each year. It was 20 to 30 feet thick when the "sodbusters" arrived.
A quick ag boom was followed by a bust as the soil was sepleted over a couple of decades. Then chemical af brought a boom again. Then the dust bowl drought blew the thing chemical soil away.
If we restored it all with organic fertilizer applied on an industrial ag scale, we could be looking at a huge shift in the GHG balance worldwide, maybe more than the 1.7 billion acres Gar mentioned. Maybe restore another billion acres in conservation land from abandoned chemical cropland.
Leaving under 2 billion acres of desert to green to get to the 10 year goal of 10 gigatons extra sequestration per year.
http://amazngdrx.blogharbor.com/blog John Schneider, Northern Wisconsin
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amazingdrx Posted 4:27 am
27 Jan 2009
By using abandoned cropland rehabilitation along with organic fertilizer in crop lands, and therefore minimzing the extra sequestration needed to reverse GHG effects, most of the sequestration could be acomplished with algae farming in the oceans.
A farm could be constructed consisting of a ring of wind/wave power stations that emit a carefully controlled amount of organic fertilizer and filter algae overgrowth through intake systems that form a large ring 100s of miles across. It would have a lot less impact than desert farming and have the added benefit of directly attacking the cO2 seawater concentration positive feedback problem.
Algae farms like this would be easy to expand rapidly with mass production of the floating wind/wave energy platforms.
Algae could be processed to yield biogas/electricity, and organic soil amendment to sequester the carbon onshore in the form of soil.
These areas would increase ocean life and could be used for floating aquaculture production. A way to revive over fished sea life is a big benefit. And boats use less energy than huge tractors carving up deserts.
http://amazngdrx.blogharbor.com/blog John Schneider, Northern Wisconsin
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Jon Rynn Posted 4:56 am
27 Jan 2009
Also, we lost about 5 gigatons of c02 per year from 2000 to 2005 in forests worldwide from deforestation, so I assume you could get that back if you reforested; then reforest what has been destroyed over the last 50 years, etc.
Interestingly, amazin', oil originally came from algal blooms in the ocean from global warming periods. From what I've read, most of the co2 uptake from the oceans is chemical, but not of biological origin, but I suppose algae could use what is there if you add it.
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