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Miocene Anthropocene Future

Miocene Anthropocene Future

Unread postby Tanada » Tue 22 Apr 2014, 19:25:43

The last time the Earth had sustained CO2 levels like those we are experiencing today was in the early to middle Miocene epoch 13-20 Million years before present. At that time there was no year around ice in the Northern Hemisphere and the Antarctic Ice Sheet was considerably smaller than it is today, so much so that global sea levels were about 35 meters, 80 feet higher than they are today.

The part of North America that includes Kansas, Nebraska, North and South Dakota and up into Canada was a desert not unlike the Sahara with white sand dunes blowing back and forth across the middle of the continent. There were no mountain Glaciers in the Northern Hemisphere and Greenland was a broad forested island with palm trees on the southern coastline.

Make no mistake, no matter if it takes 1,000 days or 1,000 years this is the world we are headed towards right now. Globally temperatures will only be two degrees warmer, but that presumes the Antarctic will change very little while the Arctic will become much more like Florida today than the frozen tundra we are used to right now. In many ways talking about climate change in terms of the global average leads to very incorrect pictures of what the future holds. Antarctica started growing its ice sheet when global CO2 fell below 780 ppmv but Greenland stayed ice free until the global level fell well below 400, perhaps as low as 350 ppmv. It has been two decades since the world average passed 350, and the consequences of that milestone are now starting to take hold of our climate.

Unfortunately the lag between cause and effect is so long humans do not intuitively make the connection. To properly experiment with climate we would have paused for three decades after each incremental rise in CO2 so we could study the effects we were having and adjust our behavior if we did not like the results. Instead we have bulled ahead dumping CO2 into the air at an ever increasing rate. By the time we get the full effects of 350 ppmv we will already have reached around 420 ppmv, making it nearly impossible to reverse course if we decide we do not like the effects of 350.
I should be able to change a diaper, plan an invasion, butcher a hog, design a building, write, balance accounts, build a wall, comfort the dying, take orders, give orders, cooperate, act alone, solve equations, pitch manure, program a computer, cook, fight efficiently, die gallantly. Specialization is for insects.
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Re: Miocene Anthropocene Future

Unread postby Graeme » Tue 22 Apr 2014, 19:57:41

Do you think the stupid fossil fuel brigade will listen to you? Hell no, they'll abuse you and keep on drilling.
Human history becomes more and more a race between education and catastrophe. H. G. Wells.
Fatih Birol's motto: leave oil before it leaves us.
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Re: Miocene Anthropocene Future

Unread postby dohboi » Tue 22 Apr 2014, 20:47:16

"Unfortunately the lag between cause and effect is so long humans do not intuitively make the connection."

I do wonder how the responses may be different if scientists conclusively found that the earth had left its orbit and was starting top spiral slowly toward the sun.

I'm betting there would be calls all over to do all sorts of things to stop or slow that death spiral.
I'm betting that it would be front page news every single day.

Yet heating the earth through GHGs amounts to the same thing, but comparatively little main stream media attention has been devoted to it. Tanada, posts like yours should be in opinion and news columns every day. But instead they are a rarity, and often counterposed with pseudo-skeptical anti-science propaganda.

Surely, as G suggests, a big part of the difference is that the it is against the short term interests of the richest corporations ever to exist for people and nations to really take the necessary actions needed to avert this global threat. It's not just the slow-motion nature of the threat, I think, that is impeding action.
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Re: Miocene Anthropocene Future

Unread postby Simon_R » Wed 23 Apr 2014, 01:14:51

How Can I buy Property in Greenland ?!?!
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Re: Miocene Anthropocene Future

Unread postby Tanada » Wed 23 Apr 2014, 07:05:45

Dohboi, scientists never conclusively find anything, there is always wiggle room because only the arrogant non scientists would assume they have everything correct with no doubts. This causes problems when non scientists gleefully proclaim X Y or Z as a fact when the scientists who are trained to study facts say it is highly probable X is true but there is always the possibility it is Y and we just do not understand the mechanism well enough. Things we assume are facts like Gravity are scientific theory, and the good scientists refer to them that way. If the Earth were spiraling in real scientists would come up with the theory of why and how long it would take and the arrogant would proclaim it was all a lie and we would be in the same place we are with the Anthropocene.

I created this thread for the purpose of discussing where we are right now in terms of the climate changes we have already set in motion, not the Guy McPherson megadoom scenario but the real scenario we project based on paleoclimate records and real science evidence.

Things over the next few decades are going to get wild and rough, if all we ever talk about are the two extremes Denierville nothing is changing and Doomerville we are all extinct then nobody will take a realistic look at the world as it will be. I want to see a realistic view discussed, that is why I made this thread. Yes things could be far worse than this thread projects, but from what we know right now this scenario is realistic as to what the near future will look like. The truth is always somewhere between the extremes, and if you believe either extreme there is no point in doing anything different today than you did last week.
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Re: Miocene Anthropocene Future

Unread postby dissident » Wed 23 Apr 2014, 07:06:11

We are set for 7 meter higher sea levels in the next few centuries from Greenland glacier melt alone. As Hanson has pointed out in one of his papers the melt is a nonlinear process and I think 2 meters by 2100 is probably too optimistic since that would be melt from all sources. And to think the IPCC was predicting 50 cm of sea level rise by 2100 in its older reports from before 2007.

The Arctic was ice free until 4 million years ago when the Panama channel closed. The global ocean circulation change associated with this is a critical factor and not just CO2 levels. I think we will have winter time Arctic sea ice for a very long time to come even as Greenland loses its ice sheet.

The success of the anti climate science and anti peak oil propaganda will help put the nails into the coffin of its sponsors in the long run. The public will experience pain from various sources, primarily food and energy costs, and will not have been informed the reason for this pain. It is docile now while BAU is relatively stable, but things will get bloody likely by 2040.
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Re: Miocene Anthropocene Future

Unread postby Pops » Wed 23 Apr 2014, 07:35:57

I'd sign on for fairly drastic measures to constrain GHG. The idea of man made pollution affecting the environment was part of my childhood so my knee jerk reaction is to think CC is happening.

I'm fairly immune to arguments from the Chamber of Commerce & God's Will camps; their angles are obvious and immutable and based on "faith", just like mine.

However, endless chanting about impending GW doom, blowing sand and boiling in my skin does nothing but make my eyes glaze over and in fact lessens my engagement on the topic. If there are only 10 seconds on the clock and your team is down by 30, there isn't much incentive to invest any more emotion in the game.
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Re: Miocene Anthropocene Future

Unread postby farmlad » Wed 23 Apr 2014, 07:45:59

To gain a perspective that seems to be left out of most discussions on atmospheric Co2 levels ,watch Tony Lovell's introduction on Ted Talks http://youtu.be/wgmssrVInP0
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Re: Miocene Anthropocene Future

Unread postby Tanada » Wed 23 Apr 2014, 07:53:42

dissident wrote:We are set for 7 meter higher sea levels in the next few centuries from Greenland glacier melt alone. As Hanson has pointed out in one of his papers the melt is a nonlinear process and I think 2 meters by 2100 is probably too optimistic since that would be melt from all sources. And to think the IPCC was predicting 50 cm of sea level rise by 2100 in its older reports from before 2007.

The Arctic was ice free until 4 million years ago when the Panama channel closed. The global ocean circulation change associated with this is a critical factor and not just CO2 levels. I think we will have winter time Arctic sea ice for a very long time to come even as Greenland loses its ice sheet.

The success of the anti climate science and anti peak oil propaganda will help put the nails into the coffin of its sponsors in the long run. The public will experience pain from various sources, primarily food and energy costs, and will not have been informed the reason for this pain. It is docile now while BAU is relatively stable, but things will get bloody likely by 2040.


World ocean circulation is definitely different than it was during the Miocene so we know the future will not be an exact replica of the past climate. One of the things we know is that ice sheets have a tipping point after which they inevitably collapse usually over a period of centuries of time and it is highly probable we are pushing well past the tipping point for Greenland or already have.

So Greenland will all melt in terms of ice sheet, it might take centuries or it might be faster but sooner or later it will all melt. What does that mean for us? Well for one thing that 7 meters is the global average, but we now recognize that the gravitational attraction of the ice sheet itself will influence how much local change takes place. Based on what I have read if all of the GIS melts and nothing else changes Brazil will see significantly more than 7 meters rise near the equator, Louisiana will see about 7 meters and Greenland's coast might actually see a sea level reduction of half a meter. In the southern hemisphere early on the AIS will pull significant water mass to itself from the local gravity distortion and this will cause the ice shelves to ride higher and possibly allow sea water to intrude more easily into the below sea level depression under the West Antarctic Ice Sheet. That in turn would feed back by destabilizing WAIS and causing it to collapse releasing between 5 and 7 meters of additional sea level rise. Dr. Richard Alley has some fascinating lectures on the possible instability of WAIS with a modest sea level rise on YouTube free for the viewing. If the Greenland then WAIS scenario plays out in this way then sea level in the Equatorial regions will get the double whammy effect as water melted from both poles will naturally collect more at the bulge around the equator than in any other location. The dynamics of how sea level is expected to change are much more complicated than most people assume, the gravitational effect of the ice sheets was presumed to be negligible until the last decade or so when researchers looked more closely at the phenomenon.

Now comes the big question mark, Lake Gatun, the highest portion of the Panama Canal route, is 26 meters above current sea level and 9 degrees north of the equator. When Greenland melts the sea level around Panama is expected to go up considerably more than 7 meters, perhaps as much as 10 or 12. This puts the lake surface much closer to sea level which makes the possibility of converting the canal into an open sea level structure much more attractive. The other factor is this Image
If you look at Columbia around the 5 degree north latitude you are at the coastal high point, about 43 meters above current sea level. This was one of the many proposed routes for a canal connecting the Atlantic and Pacific basins and if sea level goes up 10 or 12 meters for the GIS and another 5 to 8 for the WAIS that brings the high point 15 to 20 meters closer to sea level. It also floods much of the coastal plain on either side of the high point making this a short dig to have an alternate sea level route between the basins. In point of fact there are several places between this spot and the mountains of Costa Rica north of Panama where a 15-20 meter sea level rise could work its way through the valleys in the mountains and connect the two basins even if humans do nothing to help things along. If the sea level gets that close to the surface of Lake Gatun the lock system would be pointless because a limited scale dredging would open up a sea level route for shipping. If we end up with the 35 meter rise globally that we had during the Miocene epoch from combined melting at both poles then the equatorial amplification will open up several sea level connections between the oceans. How that will effect the climate of the two hemispheres is a matter of speculation, we know northern winters were relatively warm until the straits closed around 3 million years ago. Will flooding the straits make winter in the Northern Hemisphere warm even further? A great deal depends on just how much water flows between the two basins. The Isthmus of Panama has been thrust up by the collision of North America and South America and is still rising today slowly as the continents get closer together.

There was no GIS until the isthmus closed, and the closing of the Isthmus dropped sea level on average 7 meters globally and more in Panama. This means raising sea level by just 7 meters is unlikely to make a large change in world ocean circulation. Even adding in the 5 meters from the WAIS is unlikely to be enough to change the circulation pattern. That makes the East Antarctic Ice Sheet the big question mark, how much will it melt in a 400 PPMV plus CO2 Anthropocene world?
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Re: Miocene Anthropocene Future

Unread postby Timo » Wed 23 Apr 2014, 08:49:21

I'll caution everyone before i get to the parallel story that this is totally irrelevant to the topic of this thread, but i post this only to illustrate how rapidly things can go from bad to worse to.....death. Here goes.

I lost a family cat on Monday. He basically adopted us, and apparently had always been a house cat, possibly abandonded by someone else. He came in through the front door, and stayed, becoming best friends with our other pets. We did the normal obligatory health checks, and he tested positive for feline lukemia, so we had our other cats vaccinated. He did perfectly fine for 7 or 8 years, until this past Sunday when he became noticably lethargic. We took him to the vet on Monday, had some blood work done, and his hematocrit was at 12%. We took him next to a university vet med hospital an hour away, hoping that a transfusion would buy him, and us, some quality time. The hospital did some more testing, and his hematocrit had declined to 8% in the course of only 4 hours. He was gone, and we made the inevitable decision to let him go.

The doctors told us that it was quite possible, perhaps even probable that his hematocrit had been in a decline for several months before things got critical and his symptoms became obvious. Unfortunately, when the symptoms of low oxygen in the blood become apparent, it was too late.

Ditto for climate change. There's a time lag between cause and effect. Yes, we humans are the cause of rising CO2 levels, but the effect takes a substantial portion of out lives to witness. In a universal timeline, our lives are a nanosecond of time, and paleonotologists 10,000 years from now will clearly be able to see a very abrupt change in our atmosphere during the 20th century. Living through that change in our "real" time, however, is slow enough that we can convince ourselves that everything is fine, and the warning signs of our cause-and-effect relationship with our planet are wrong. We are weak and cannot admit the truth. That is our ultimate deadly sin. Unfortunately, we've not noticed the symptoms of our demise until it's now too late. The end will come very quickly, now. We've crossed that threshold where momentum cannot be stopped, and it will gain speed from here on out. I doubt anyone alive today will live to see the apex of where we're headed, and there may be a lucky few who are able to adapt to fit the new norms, but they will be few.

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Re: Miocene Anthropocene Future

Unread postby Pops » Wed 23 Apr 2014, 08:53:20

We're dead - eyes glaze - take a drive.

LOL
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Re: Miocene Anthropocene Future

Unread postby Lore » Wed 23 Apr 2014, 09:12:22

The conclusion suggests that there will be no paleonotologists in 10,000 years.
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Re: Miocene Anthropocene Future

Unread postby rockdoc123 » Wed 23 Apr 2014, 09:15:16

According to AR5 WGI chapter 13 Greenland contribution to sea level rise under a 500 – 700 ppm CO2 scenario is somewhere between 0.1 m and 0.5 m by 2500. At > 700 ppm CO2 Greenlands contribution to sea level rise doesn’t reach a metre until 2300. Antarctica under the 500 – 700 ppm CO2 scenario has negative contributions to sea level right through until 2500 with increased precipitation actually increasing Antarctic mass balance on a continuous basis from 2100 through 2500. Under the > 700 ppm CO2 scenario Antarctic contribution to sea level rise is somewhere between 0.1 and 0.9 m by 2500 but is insignificantly positive until 2400.

Under the 500 – 700 ppm Co2 scenario overall sea level rise is in the range of 0.2m to 1.7 m by 2500 and doesn’t reach over 1 m until 2300. Under the >700 ppm CO2 scenario sea level rise reaches above the 1 m level by 2200 and by 2500 is somewhere between 2 and 6 m .
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Re: Miocene Anthropocene Future

Unread postby Tanada » Wed 23 Apr 2014, 09:37:37

Pops wrote:We're dead - eyes glaze - take a drive.

LOL


That is kind of my point Pops, I don't think we are dead, or at least not nearly all of us. That is what I mean by adopting the extreme as a way of ignoring the path through where we are to where we are going.

Life is ultimately about change, you are born, you grow, you age, eventually you die and decay. In between is constant change and fighting it will not stop it. No matter how much plastic surgery Joan Rivers gets she will still meet her end just like the rest of us. Maybe she will be a pretty corpse, but a corpse she will be :-D

We have shifted the climate of the planet, it just hasn't dropped into its new groove all the way yet. Sooner or later it will, and when we stop pushing it the natural forces will take over slowly pulling it back to the pre industrial pattern over several thousand years. The further we push it the longer the pull back will take.
I should be able to change a diaper, plan an invasion, butcher a hog, design a building, write, balance accounts, build a wall, comfort the dying, take orders, give orders, cooperate, act alone, solve equations, pitch manure, program a computer, cook, fight efficiently, die gallantly. Specialization is for insects.
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Re: Miocene Anthropocene Future

Unread postby Pops » Wed 23 Apr 2014, 10:00:01

Joan Rivers isn't dead! ?

LOL she's got that flip-top head thing going - I thought it was to get dem brainz!
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Re: Miocene Anthropocene Future

Unread postby Lore » Wed 23 Apr 2014, 10:27:57

The new groove is several hundred years away and who can say how compatible that will be with life on the planet? Other then to be certain it will be far less conducive to existence then our present, and rather small period, of time.

My feeling is that it's a real crap shoot with a mixture of magical thinking to believe that there will be much more than scattered handfuls of us left. Driven to the brink by a rapidly changing environment, conflict, disease, lack of energy, water and technology to shield and protect us.

I guess we can take comfort that those of us present right now got the full ride. I'm less convinced though that being ambivalent about the process serves a usefull purpose other then to pretend that bad things just don't happen.
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Re: Miocene Anthropocene Future

Unread postby Plantagenet » Wed 23 Apr 2014, 10:50:43

rockdoc123 wrote:According to AR5 WGI chapter 13 Greenland contribution to sea level rise under a 500 – 700 ppm CO2 scenario is somewhere between 0.1 m and 0.5 m by 2500. At > 700 ppm CO2 Greenlands contribution to sea level rise doesn’t reach a metre until 2300. Antarctica under the 500 – 700 ppm CO2 scenario has negative contributions to sea level right through until 2500 with increased precipitation actually increasing Antarctic mass balance on a continuous basis from 2100 through 2500. Under the > 700 ppm CO2 scenario Antarctic contribution to sea level rise is somewhere between 0.1 and 0.9 m by 2500 but is insignificantly positive until 2400.

Under the 500 – 700 ppm Co2 scenario overall sea level rise is in the range of 0.2m to 1.7 m by 2500 and doesn’t reach over 1 m until 2300. Under the >700 ppm CO2 scenario sea level rise reaches above the 1 m level by 2200 and by 2500 is somewhere between 2 and 6 m .


Consider just the near future.

Current sea level rise is about 3 mm/yr. Thus by 2100 we might expect about 25 cm of rise if current trends continue. But the rate of sea level rise has been accelerating, so the rise is likely to be more than 25 cm---perhaps 0.5 m or more.

Expect coastal erosion and shoreline retreat, and more damage from storm surges and flooding of low lying areas in coming decades.

The coastal erosion is under-appreciated. Wave action creates gently dipping shore platforms just offshore---these dip seaward at 3-7°, so sea level rise will cause these to grow, resulting in hundreds of feet of erosion of shorelines.

Its a bummer for people living along beaches.

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Re: Miocene Anthropocene Future

Unread postby dohboi » Wed 23 Apr 2014, 12:29:05

T wrote: "I created this thread for the purpose of discussing where we are right now in terms of the climate changes we have already set in motion, not the Guy McPherson megadoom scenario"

I'm a bit confused by this. Did I bring up McPherson somewhere? I was talking about how big of a role the (apparent) gradualness of CC had on peoples (lack of) response to it, and I tried to come up with a comparable situation that might still be gradual but that I thought more people would likely respond more dramatically to. Sorry if I wasn't being clear about that.

I will point out that just a few years ago if someone claimed that the Arctic Ocean would be virtually ice free by at the end of summer within a couple decades, people could have accurately pointed to dozens of scientifically based models none of which were showing any possibility of such a rapid response. But here we are now, with ice volume down to the point that many see such a possibility as quite likely.

The two poles of "extremes" are not equally improbably. There is a very "fat tail" in the probabilities that lean toward things unraveling faster and further than the median projections. That, too, is science. But there is essentially no 'tail' of probability that GW will suddenly reverse itself and we will suddenly get back to the "goldilocks" climate we have enjoyed in the last 10,000 years or so.

I, too, have been looking at the possibility of a breach in the Panamerican Isthmus, but I hadn't thought about the possibility of that development changing ocean currents. Would any such channel be deep enough to have such effects, I wonder? In any case, even with rapid accelerations of SLR, we are not likely to see such development for a few centuries, and a whole lot of other really bad developments will have...preoccupied humanity by then, I suppose.

I think the Sahara-like sand dunes you mention blowing across much of Central North America are a much more likely scenario in the relatively short term, since something like this was the situation just a few hundred years ago. It is one of the first things mentioned as likely to take place even with a one degree C rise in global temperatures in Mark Lynas's carefully researched book Six Degrees.

Pops, is that the kind of prediction that makes your eyes glaze over? If so, I would recommend not reading that book, or for that matter any scientific literature on the subject. Same with the scientific literature on wet bulb temperatures (if that's what you meant by 'boiling in our skins').

Perhaps sticking to reading up on Joan's latest coiffure would be safest after all? :lol:
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Re: Miocene Anthropocene Future

Unread postby Tanada » Wed 23 Apr 2014, 13:18:21

dohboi wrote:T wrote: "I created this thread for the purpose of discussing where we are right now in terms of the climate changes we have already set in motion, not the Guy McPherson megadoom scenario"

I'm a bit confused by this. Did I bring up McPherson somewhere? I was talking about how big of a role the (apparent) gradualness of CC had on peoples (lack of) response to it, and I tried to come up with a comparable situation that might still be gradual but that I thought more people would likely respond more dramatically to. Sorry if I wasn't being clear about that.

I will point out that just a few years ago if someone claimed that the Arctic Ocean would be virtually ice free by at the end of summer within a couple decades, people could have accurately pointed to dozens of scientifically based models none of which were showing any possibility of such a rapid response. But here we are now, with ice volume down to the point that many see such a possibility as quite likely.

The two poles of "extremes" are not equally improbably. There is a very "fat tail" in the probabilities that lean toward things unraveling faster and further than the median projections. That, too, is science. But there is essentially no 'tail' of probability that GW will suddenly reverse itself and we will suddenly get back to the "goldilocks" climate we have enjoyed in the last 10,000 years or so.

I, too, have been looking at the possibility of a breach in the Panamerican Isthmus, but I hadn't thought about the possibility of that development changing ocean currents. Would any such channel be deep enough to have such effects, I wonder? In any case, even with rapid accelerations of SLR, we are not likely to see such development for a few centuries, and a whole lot of other really bad developments will have...preoccupied humanity by then, I suppose.

I think the Sahara-like sand dunes you mention blowing across much of Central North America are a much more likely scenario in the relatively short term, since something like this was the situation just a few hundred years ago. It is one of the first things mentioned as likely to take place even with a one degree C rise in global temperatures in Mark Lynas's carefully researched book Six Degrees.

Pops, is that the kind of prediction that makes your eyes glaze over? If so, I would recommend not reading that book, or for that matter any scientific literature on the subject. Same with the scientific literature on wet bulb temperatures (if that's what you meant by 'boiling in our skins').

Perhaps sticking to reading up on Joan's latest coiffure would be safest after all? :lol:



That wasn't a shot at you dohboi, I was just trying to clarify what I want this thread to be about.

I certainly agree some things have changed vastly more rapidly than anyone had predicted. Ten years ago the models said it would be at least 2070 before seasonally ice free conditions would occur in the Arctic Ocean. Now we can reasonably speculate it could happen THIS YEAR! It still isn't highly probable that it will happen this year, but it is now within the realm of the possible.

IMO it all boils down to what positive feed backs kick in vs the negative feed backs that have been keeping the climate stable up until now. Losing the sea ice albedo effect is adding very large quantities of energy to the North Pole both specifically and regionally. The extended intrusion of the gulf Stream into the Arctic basin is another amplification of Northern warming. The 'sticking' of weather patterns is yet another impact, when one of them drawing warm air north gets stuck spilling warm air over Greenland it causes a melt effect like we saw in 2012. Yes it was brief, that last time, but it need not be brief every time it does happen and the effect is both wide spread and extreme. It we lose an extra meter of ice a year from such events the cumulative losses will add up rather quickly, as will the sea level rise that they cause. Ice is a huge heat sink before it melts, so every cubic meter melted reduces the heat sink capacity, which is a current negative feed back.

The fat tail of climate change is why I pointed out that weather Greenland melts in 1,000 days or 1,000 years it will all melt. I tend to think it will be much quicker than the IPCC models rockdoc123 has faith in, but they could be right and I could easily be wrong, they research and study these things exhaustively and presumably don't publish a prediction without having a very high confidence in its accuracy.
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Re: Miocene Anthropocene Future

Unread postby TemplarMyst » Wed 23 Apr 2014, 13:32:51

Tanada,

Thanks for starting the thread. Having spent some time over on Guy's site it can be a tad overwhelming, in terms of trying to have a conversation about what might be done. The assumption there is it's over, so why bother talking about possibilities?

Since I'm inclined to looking at changes that might be made, I keep thinking we would want to look at some way humans might more actively manage the carbon cycle, since that seems to be at least one of the more obvious areas where we've done some geoengineering without really intending to do any geoengineering at all.

However, I'll be the first to admit even considering such an idea is intensely intimidating. The scale is enormous, the possible unintended consequences daunting, and the technology completely unknown, undefined, and undeveloped.

I mean, we clearly know how to throw carbon up into the atmosphere. And we're clearly really good at it too. And at least some of us have come to realize that probably wasn't such a bright idea, though most of us have come to that realization rather late in the game, to be sure.

In past posts you've mentioned some of the known ways carbon cycling could, or might, be accomplished. Reforestation, changes in land management, biochar, and a few others.

I guess my question is whether a simple mechanical process might be viable. I've mentioned in past posts the idea of using nuclear power to drive a mechanical filtration system that feeds a chemical processing plant. Instead of vast Walmart warehouses, buildings of similar size and scope for this purpose.

At the end of the day we've combusted hydrocarbons to produce all sorts of goods and services that have benefited humanity - food, running water, heating for homes, etc, etc. In the process we've consumed the material that provided those benefits; the material doesn't regenerate very easily, and it seems to be heating the place up overall in ways we ain't too sure will be good.

Given the energies involved, and the scales involved, it seems to me this sort of thing would only really be viable if the actinides are brought into the picture. Their energy densities are so massive I'm thinking they might be able to power what would otherwise be thermodynamically improbable, if not outright impossible.

Anyway, I thought I'd raise this idea again and bounce it off folks. See if anyone thinks it's even worth thinking about further.
TemplarMyst
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