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Rob Painting at 06:03 AM on 5 April 2014Alarming new study makes today’s climate change more comparable to Earth’s worst mass extinction
MP3CE - a simplified answer:
Higher atmospheric CO2 concentrations result in more CO2 dissolving into the oceans, despite warmer ocean temperatures (See Dalton's Law of Partial Pressures and Henry's Law). Basically, if you increase the pressure of CO2 in the atmosphere it will dissolve more CO2 into the ocean. Less CO2 in the atmosphere during the last glacial maximum, for instance, meant lower partial pressure and consequently lower dissolved CO2 in the ocean.
Because pH is a negative logarithmic scale, higher pH indicates a lower concentration of hydrogen (hydronium) ions in seawater. With lower atmospheric CO2 at the last glacial maximum, there would have been fewer hydronium ions in seawater. Therefore pH would have been higher than today and, all things being equal, it would have been more conducive to shell-building in marine organisms than today.
The general response indicated in the image above is correct.
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howardlee at 04:54 AM on 5 April 2014Alarming new study makes today’s climate change more comparable to Earth’s worst mass extinction
Criskoz - yes I am referrring to the Rothman et al 2014 paper. You are correct, it is a real paper not an April fool, and although it hit the headlines on April 1, it was realeased before. From my reading of the Rothman paper they were attributing the cause of the carbon emissions primarilty on microbes (with fertilization by nickel from the Siberian Volcanics). On the one hand you are correct - the way the climate responded to a huge slug of carbon - irrespecive or source - is a stark warning for us today.
But on the other hand LIPs have a long track record of these kinds of changes, whereas the microbe mutation idea is a 1-off explanation. Aside from establishing the true cause intellectually, establishing the true cause helps us understand how comparable the Permian (or Triassic or Toarcian etc etc) events are to today. A chance microbe mutation a couple of hundred million years ago has no applicability to today.
Yes LIPs are not your average volcanoes - they are a very differnt animal altogether. Every year there are something like 50 to 65 volcanic eruptions, but we haven’t had a LIP eruption in 16 million years. They are apparently related to mantle plumes delivering copious quantities of superhot, superliquid lava from the lower mantle to the surface and injecting in sheets and fissures through the crust - like internal bleeding. Their lava flows are so copious they can flow for over 1,500 km. A single LIP can cover 1% of the planet's surface in lava.
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howardlee at 04:30 AM on 5 April 2014Alarming new study makes today’s climate change more comparable to Earth’s worst mass extinction
Tom - I defer to your greater knowledge on luminosity and forcing calculations.
regarding Permian ice-age conditions there was southern glaciation in early to mid Permian, at least at higher elevations. According to this paper, even in the late permian there were frigid conditions with permafrost in the southern part of of the world. We would have to drill down to those specific late Permian data points to figure out what's going on there. According to the Isbell et al paper linked to in this comment, CO2 levels rose markedly at the end Guadalupian - concident with the Emeishan LIP eruptions. The environmental effects of that were ongoing (this paper and this) when the P-T extinction hit.
The Permian supercontinent configuration, with land stretching from pole to pole, would undoubtably have different ocean currents than today, with much more north-south heat distribution than is possible in today's world with the Antarctic Circumpolar Current.
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howardlee at 03:47 AM on 5 April 2014Alarming new study makes today’s climate change more comparable to Earth’s worst mass extinction
MP3CE - I recommend you download Prof Zeebe's paper - it explains it all.
But essentially, colder oceans can dissolve more CO2 than warmer oceans.
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KR at 02:49 AM on 5 April 2014Honey, I mitigated climate change
Michael Whittemore - We're way off-topic for SkS now; I believe such a discussion would be more appropriate to a forum more focused on space based solar power; not here.
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Michael Whittemore at 02:04 AM on 5 April 2014Honey, I mitigated climate change
KR do you mean generate the power in space and beam it down? Because that is a massive under taking and does not change the fact that land based stations need to work at night.
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KR at 01:54 AM on 5 April 2014Honey, I mitigated climate change
Michael Whittemore - Don't forget the column of blue sky reaching into the high troposphere due to non-directional Rayleigh scattering of sunlight. That's going to be faint but visible for quite a distance...
I suspect that it will be more politically approachable to use microwave power transmission to dedicated facilities.
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Michael Whittemore at 01:36 AM on 5 April 2014Honey, I mitigated climate change
KR at 00:00 AM on 5 April 2014
It would only light up a km of land. You would not be able to see the light in the sky only if it hit the clouds. Even then it would be like a full moon or a sports stadium or a lite up car park. Maybe some solar farms night not make the cut but it's by far no show stopper.
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KR at 00:00 AM on 5 April 2014Honey, I mitigated climate change
Michael Whittemore - It's difficult enough when people complain about the 'eyesores' of windmills. Can you imagine the local residents NIMBY protests when the solar mirrors eliminate night?!? I don't think that's going to happen...
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Michael Whittemore at 21:03 PM on 4 April 2014Honey, I mitigated climate change
CBDunkerson at 02:14 AM on 31 March, 2014
With large solar farms and molten salt power stations already developed, I think it would still be good to have a system of mirrors that would keep these power stations active through the night. Even if there was cloud cover, the light could be redirected to other sites at a more intensive setting. These mirrors would only produce 100% of the sun’s rays which would reduce the chance of birds or planes having an issue. With the light only being directed on small sections on the surface of the Earth, I would think its affects would be minimal. A positive is that most ground based stations do not take up huge amounts of space, reducing the amount of mirrors needed. Most power usage happens in the evening, so the satellites could be very selective and only power stations at key times during the night. A joint venture between power stations around the world would make it reasonable cheap.
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MP3CE at 20:14 PM on 4 April 2014Alarming new study makes today’s climate change more comparable to Earth’s worst mass extinction
Hi,
I've some question for a thing which I cannot grasp regarding the first picture. The problem I have is that at 280 ppm CO2 in atmosphere and less of it dissolved in oceans, I'd expect lower pH in ocean than at 200 ppm, but the images shows the opposite (pH is higher when atmospheric concentration is at 200 ppm). I guess there must be something more, but it is somehow unclear what mechanism is behind this. I will appreciate more detailed explanation (P.S. if I've missed a link and you consider this off topic, I apologize, but I'd be grateful to point me into right direction).
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Doug Hutcheson at 17:47 PM on 4 April 2014Alarming new study makes today’s climate change more comparable to Earth’s worst mass extinction
Can we seriously expect Earth’s climate to behave differently today than it did at all those times in the past?
Yes, because we now have politicians who are committed to legislating physics into submission. Those previous events were politician-free, so there is no comparison to be made with today. Some claim politicians change polarity over multi-year cycles in much of Earth's landmass, but these mysterious 'cycles' have not been adequately explained by political scientists, so may be regarded as nothing more than arm-waving by activists.
Personally, I see little change in polarity between the little red ones and the little blue ones (both spinning more or less to the right), although some of the little green ones exhibit stronger polarity differences (spinning to the left in general) and these have developed thicker shells.
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chriskoz at 17:02 PM on 4 April 2014Alarming new study makes today’s climate change more comparable to Earth’s worst mass extinction
Tom@11,
Thanks. Having read your last paragraph @9 (originally I did not pay attention to it because of your false premise/typo), I need to add that the equatorial extinction as described in (Burgess et al 2014) does not result from the strength of positive climate forcings in that region.
As you note, forcings change the energy budget and the changes are not homegeneous. However the actual local warmings are usually not the same as the local forcings, because the heat transfer within AO. For example, we know that highest rate of warming the Arctic ice is currrently experiencing results from heat transfer via ocean currents, whereas Antarctic ice sits on land so does not enjoy heat exchange as fast as Arctic.
Secondly, the actual local warming (expressed as dT) does not necessarilly correlate with the ensuing local extinction. The T stress on organisms depends mainly on the number and the duration of extreme events expressed as the n-sigma departure from the original T variability to which the organisms are adapted. Over equator hovewer, the variability is much lower than over the poles so even small dT causes large stress.
Finally, heat is not the only factor in the extinctions. As you can see from the pictures in the article, the ocean acidification was the big factor in Permain extinction of the ocean creatures. While even relatively smaller dT changes could still extint land creatures per my second point above.
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Tom Curtis at 15:36 PM on 4 April 2014Alarming new study makes today’s climate change more comparable to Earth’s worst mass extinction
Sorry Chriskoz, complete brain fart there. I had intended to type "Increased solar luminosity has a far greater warming effect on the equator". If you switch to the correct word, you will find the rest of the paragraph makes far more sense. I apologize for the confusion.
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chriskoz at 14:25 PM on 4 April 20142014 SkS Weekly News Roundup #14A
A little bug, perhaps of interest to Bob:
The links to comment counters on the sks home page in the article previews, starting from this article began showing values real_number_of_comments+, i.e. "3 comments" when there are realy only 2 comments that you can view by clicking at the actual link.
Nothing important (just a misleading statement that SkS threads are slightly more popular) but I wonder how the HTML server can produce such a bug...
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chriskoz at 13:23 PM on 4 April 2014Alarming new study makes today’s climate change more comparable to Earth’s worst mass extinction
Tom@9,
one curious effect of the change of luminosity is to change the balance of heat between poles and equator. Increased solar luminosity has a far greater warming effect on the poles, while that from GHG warms more in mid-high latitudes.
Can you point the source of your claim? How do you reconcile your claim with the known facts about solar incoming short length solar vs. outgoing long length IR, as measured by satelites? For example anual average here:
where we can clearly see that solar absorbtion dominates on the equator. Therefore, with increased TSI and all other things equal, one would expect the increasing warming over the equator, contrary to your claim.
On the other hand, the satellite date on OLR looks like this (top - absolute values, bottom - S deviation):
The biggest IR is at mid-lattitudes. So that data supports your assertion that "[positive forcing from] GHG warms more in mid-high latitudes"
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One Planet Only Forever at 13:10 PM on 4 April 2014Earth has a fever, but the heat is sloshing into the oceans
I totally agree with the potential misleading impression obtained from tracking the trend of shorter time periods. I personally prefer to use a simple spread sheet to follow the rolling 30 year average of the GISTEMP Land-Sea monthly average (a new 30 year average for every new month). That 30 year average continues to rise with the values continuing to be more than 0.16 degrees warmer than a decade before.
Also, it is clear that the phase and magnitude of the ENSO has a significant influence on the global average surface temperature, and it can be a long unpredictable amount of time between significant El Nino influences (such as the current 17 years and going since the 1997/98 El Nino). Any time period that does not include the full range of these significant influences would not really provide a reliable representation of things.
A more interesting point is that even with the extremely high variability of monthly global average surface temperatures (as much as a 0.54 degree C difference from one month to the next in the GISTEMP data set), each month in GISTEMP since 1993 has been warmer than the month 30 years before it, except for January 2011 which was 0.05 degrees cooler than January 1981.
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Tom Curtis at 11:01 AM on 4 April 2014Skeptical Science Study Finds 97% Consensus on Human-Caused Global Warming in the Peer-Reviewed Literature
paulhtremblay @305, the information you are after is given in summary form on table 5 of the paper:
Position Abstract rating Self-rating
Endorse AGW 791 (36.9%) 1342 (62.7%)
No AGW position or undecided 1339 (62.5%) 761 (35.5%)
Reject AGW 12 (0.6%) 39 (1.8%)As you can see, the abstract ratings sigificantly underestimated endorsements relative to the author self ratings. They also underestimated rejections, but massively over estimated "no position" papers. That is unsurprising in that the abstract ratings were done on the basis of the abstract and title alone, with no information about authors, time or journal of publication, nor the detailed contents of the papers. The authors, on the other hand had all of that information, plus information about their own intentions.
It is interesting to note that at least one of the authors who had papers "misrated" by abstract rating also responded to the author rating. Despite that, he emphasizes is unusual case ahead of the overall author rating statistics. Indeed, poptech also neglects the overall statistics, prefering cherry picked anecdotes to statistics from a large sample of respondents. Further, some of those cherry picked examples can easilly be shown to be incorrectly rating their papers.
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Tom Curtis at 10:47 AM on 4 April 2014Alarming new study makes today’s climate change more comparable to Earth’s worst mass extinction
howardlee @6:
You have scaled the rise in solar luminosity with time linearly, whereas the best simple approximation is:
L=L0/(1+0.4*((T0-T)/T0)
where L0 is the current luminosity, T0 is the current time, and L and T are the luminosity and time at the time of interest. I believe this formular breaks down prior to 4 billion years ago, but otherwise is accurate. My estimate of 2.14% less luminosity is based on that formula, for a time of 250 million years ago. For 252 million years ago the reduction is 2.16%.
Based on Breecker et al, I have estimated approximate CO2 levels of 390 ppmv for the late Permian, and 1,390 ppmv for the early Triassic immediately following the Permian/Triassic extinction. With the solar luminosity estimate, that becomes equivalent to a change from 150 to 530 ppmv today. The 150 is a very low value, suggesting ice age conditions prevailed in the late Permian, something known not to be true. Consequently, if Breecker et al are correct, either the Earth's albedo was less at the time, or the continental configuration discouraged ice age conditions, or both.
Regardless, the change in forcing is equivalent to a change in forcing from 280 to 1000 ppmv. Because greenhouse forcing is a log function of CO2 concentration, the lower estimated CO2 levels reduce the apparent threat of a Permian extinction event hothouse, while still leaving it well within the range of an aggressive (or sustained) BAU. At the same time, they increase the apparent risk of Permian extinction event like ocean acidification levels.
Again, all calculations are for indicative purposes only. I certainly lack sufficient information on Permian albedo etc to make exact comparisons.
Finally, one curious effect of the change of luminosity is to change the balance of heat between poles and equator. Increased solar luminosity has a far greater warming effect on the poles, while that from GHG warms more in mid-high latitudes. For the same level of forcing, with more GHG forcing and less solar forcing (as in the Permian extinction), we would expect less warming at the equator. Despite this, you point to a paper indicating that the equatorial regions became inimical to life due to heat in the aftermath of the Permian extinction. That strongly suggests that pushing BAU to Permian extinction levels will result in equatorial regions even more inimical to life.
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chriskoz at 09:17 AM on 4 April 2014Alarming new study makes today’s climate change more comparable to Earth’s worst mass extinction
howardlee@6
...no, it wasn't triggered by microbes, as a recent (April-1st) paper has suggested. I plan a follow up post on why that isn't plausible...
Are you talking about this (Rothman et al 2014) paper (also press release)? Both links seem to be living happily at the time herein and it seems strange that such apparent April's Fool joke is still there, not debunked/taken out. To be precise, the press release is dated 31 March 2014 while the article approval date is February 4, 2014 so I would not say it is April's Fool based on those dates.
In any case, (Rothman et al 2014) does not invalidate the conclusions from the study at hand here. In the end it does not matter what was the direct source of carbon, with respect ot the efects such release. I note however, that if we assume 100% of that release came from volcanoes, and that the rate of release was close to current antropogenic release, then we conclude that such volcanic activity be an extreme outlier - 100 times faster than the natural rate of CO2 outgassing, and lasting continuously for few centuries or 10 times faster for few millenia. Is it geologically possible?
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paulhtremblay at 09:10 AM on 4 April 2014Skeptical Science Study Finds 97% Consensus on Human-Caused Global Warming in the Peer-Reviewed Literature
I read the details of your study more closely for the first time after it was challenged by Popular Technology:
http://www.populartechnology.net/2013/05/97-study-falsely-classifies-scientists.html
I can't tell the truth behind the claims of Popular Technology. From what I can tell, a handful of papers might have been incorrectly classified, though it also seems possible that these papers were classified correcty after all.Can anyone shed light on the number of papers improperly classified? An update to this posting addressing this issue would really help.
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sidd at 05:13 AM on 4 April 2014Earth has a fever, but the heat is sloshing into the oceans
I repeat my suggestion that the first few comments to a thread be held for a brief period and then posted in randomized order, precisely to prevent attempts at threadjacking that we see here in the first comment.sidd -
howardlee at 02:54 AM on 4 April 2014Alarming new study makes today’s climate change more comparable to Earth’s worst mass extinction
One Planet Forever - to your point that it is about more than CO2, it's a valid point. We have many fingers in the machinery of our climate, and the environment generally.
And to that point, Burgess et al suggest that the effects of the Permian extinction unravelled in a cascade over 60,000 plus years, in a kind of domino effect across different niches and ecosystems.
Even if we cease all CO2 emissions today, we would still have multiple other effects ongoing with climatic and environmental effects (soot, methane, land use, etc etc). But CO2 is the major, most existential threat right now, so I believe it is correct to focus effort on it's reduction commensurate with the risk it poses to our kids and our grandkids and their descendents.
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howardlee at 02:35 AM on 4 April 2014Alarming new study makes today’s climate change more comparable to Earth’s worst mass extinction
Terranova: to add to what Tom said,
Emissions volumes Svensen 2013 and 2009 has estimated 10E3 to 10E4 Gt Carbon but he can't separate out the individual components: "magmatic volatiles depend on both total content and oxygen fugacity (CO2/CO, SO2/H2S), whereas the sediment degassing is mostly depending on the sediment type and the organic carbon content. Since both carbonates and organic matter (+petroleum) is present in the Tunguska Basin, CO2+CH4 are generated but CO2 should dominate in the carbonate dominated lithologies" (Svensen pers comm).
As for the CO2 levels - more recent proxy data than Tom quoted put late Permian CO2 levels broadly similar to today. Mid Permian levels were higher at around 1000 to 2000 ppm, but early Permian CO2 levels were at today's levels or below (there was a significant ice age then).
The Permian sun was about 1.6% less bright (taking a 30% increase over 4.6 billion years and scaling it to 252million years). That's more than the TSI variation in our modern solar cycle but it was close enough to modern levels by the Permian.
The rates that those grreenhouse gasses were emitted depends on taking those estimated volumes and dividing them by the timeframes of emission - which is why dating is axiomatic. The biggest individual flow and pipe degassing events are considered by workers in the field to have taken place over a 1-100 year timeframe. By showing that the Permian emissions occurred faster than the slow compensation mechanisms (weathering etc) and at rates in the ballpark of modern emissions, from CO2 levels not far off modern values (geologically speaking), Burgess et al have shown that - as Tom says - we can't rule out a Permian-like (or Triassic-like, etc) event at the extreme end, with business-as-usual emissions continuing.
And no, it wasn't triggered by microbes, as a recent (April-1st) paper has suggested. I plan a follow up post on why that isn't plausible, although microbes may well have had a role.
The takeaway from this article was that big, geologically-rapid greenhouse gas emissions have a long track record of being very destructive to the planet. We repeat that exercise at our peril.
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Tom Curtis at 18:52 PM on 3 April 2014Alarming new study makes today’s climate change more comparable to Earth’s worst mass extinction
Terranova @4, based on figure 3A of Royer (2006), late Permian CO2 levels were around 2300 ppmv, while end Permian and very early Triassic levels were around 3300 ppmv. These figures have very low temporal resolution, and my not be accurate for the million years on either side of the Permian/Triassic extinction - but I will use them as a working hypothesis.
Based on these figures, there was a CO2 forcing relative to the preindustrial era of 11.3 W/m^2 prior to the end Permian extinction, rising to 13.2 W/m^2 after. Of course, the sun was also less active at the time of the end Permian extinction - 2.14% less active to be precise. That equates to a solar forcing of -5.1 W/m^2. The net change in forcing was, therefore, from 6.2 to 8.1 W/m^2; equivalent to the change in forcing from 464 to 610 ppmv, ie, the change in forcing from about twenty years from now to early to mid twenty-second century with BAU.
Of course, these figures are far from definitive. For a start, the temporal resolution of the CO2 concentration figures are far too inadequate to draw any strong conclusion. Further, I have not accounted for changes in albedo due to changes in position of the continents, and the lack of large ice sheets at or near sea level in the late Permian. I certainly would not conclude from these figures that we are facing an end Permian extinction with BAU, although I cannot exclude it either. What I can conclude is that any argument that start with the high CO2 levels in the Permian and concludes that nothing similar could happen now is simplistic in the extreme. It almost certainly does not factor in the cooler Permian Sun, let alone a host of other relevant factors.
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ranyl at 17:46 PM on 3 April 2014Honey, I mitigated climate change
I did my footpirnt using the calculator below at it was 0.41tonnes a year
No obvious diet and not sure about infrastructure though.
From this the Gov and Capital from countrty cost me 4 tonnes a year.
Diet is vegan so 1.5 tonnes a year to add on.
So from me alone (actually taking all my partners electricity usage in house) 1.9 tonnes, but plus UK infrastructure 5.9 CO2 tonnes per year.
That doesn't include work emissions, however liek said 60% at home and low energy place, but still probably double my emissions and work could do more.
So with taking my share of UK government then still not great as average in UK 11.0 TCO2e per capita, which seems low a half of that just UK Gov stuff and if you put a standard amout of things and 1 flights etc the figure for personal goesto 3.92 tonnes a year, so I use 3.5tonnes less than average on that calculator, so if very one in UK reduced like that that wouldsave 210 million tonne andthe UK uses 569 tonnes.
So my first estimates was power from bills and working out log use for house, but from above, just being a UK citizen costs me twice my personal carbon emissions.
So I can't go much further personally so it is just living here in the UK adds lots.And I suspect at present that not many could do it no.
Still would be quite a saving but still along long way to go, and sure that isn't properly takign into account international trade, and other stuff like CO2 emissions for biomass etc that well.
So a long way to go really for UK, but considering the situation of a carbon debt adding in a lot of additional infra structure is all still adding.
Going to take a radical shist in thinking to get to be being CO2 negative.
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Terranova at 13:16 PM on 3 April 2014Alarming new study makes today’s climate change more comparable to Earth’s worst mass extinction
Can you give some numbers pertaining to CO2 levels during the Permian extinction event?
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One Planet Only Forever at 12:01 PM on 3 April 2014Alarming new study makes today’s climate change more comparable to Earth’s worst mass extinction
Another great article about the threat humanity faces that some among the poulation do not care to better understand.
I appreciate that the focus of this site is the improvement of understanding related to global warming/climate change, however, I believe it is important to frequently include mention that burning fossil fuels produces more negative consequences than the excess CO2. Also, many other unsustainable and damaging activities have 'developed' in the 'developed' nations and are being developed in the developing nations. The socioeconomics of popularity and profitability have led to the rapid development of unsustainable and damaging activities any way they can be gotten away with. That is what needs to be challenged. And it is why efforts to lead to better understanding of CO2 impacts have prompted such persistent and aggressive attacks.
These 'developed and developing' activities clearly cannot be continued by even just a few humans through the hundreds of millions of years that this amazing planet should be able to support a robust diversity of life. In addition, the fighting to try to get the most benefit from the limited unsustainable and damaging activities creates massive social justice harm, including the collateral death of bystanders in the vicious conflicts that erupt over control of these opportunities.
Keep on raising awareness of the concern regarding CO2, but I recommend adding in these other reasons the current 'developed ways' are so fatally flawed. Reduced CO2 is only part of the solution (and why I am opposed to suggestions that Carbon Capture should be considered a part of the solution, it should only be an added required temporary action on top of rapidly curtailing the burning of fossil fuels).
So many other popular and profitable activities need to be curtailed, and that is why issues like CO2 emissions, social justice (including things like the patently obvious need to eliminate the production and use of land-mines), environmental protection, and reduction of consumption of artificial mass-production face such hostile attack. All of these clear indications of the unacceptability of what has been developed threaten those who want to continue to benefit as much as possible any way they can get away with.
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scaddenp at 11:00 AM on 3 April 2014Honey, I mitigated climate change
ranyl, what you are talking about goes into the area of long-term sustainability, which is far beyond the immediate issue of dealing with climate change. If you want end all mining, then first you stabilize population, otherwise you lock-in the haves/haves not. Hopefully the world will do this through reduced fertility rather than increased mortality.
There is a cost to mitigating climate and there is a cost to adapting to changed climate with a lot of issues of equity. Any cost estimate that makes a reasonable guess at the scale of climate change says its cheaper (and more equitable) to mitigate. Any slowing of CO2 emissions will reduce adaptation cost.
What is not helpful is insistance on particular solution or particular political system. Nor is it helpful to scream doom when the science doesnt support such a prognosis.
I dont think it fair to ask you to show us your numbers, but I struggle with your estimate of energy use and wonder how you have accounted for public services, embodied energy in infrastructure etc. If you have energy use at level of Panama in a country with the infrastructure of UK, then you are doing well. Do you believe everyone in UK, Europe, USA (including the iced-in states) are capable of doing the same?
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Tom Curtis at 10:50 AM on 3 April 2014Climate Models Show Remarkable Agreement with Recent Surface Warming
Klapper @43, I apologize for my insufficiently carefull reading of my post. Never-the-less, looking at the effect of adding just eight years data on thirty year trends is little better than focusing on eight year trends. You are still basing your claims on the effects of short term fluctuations, albeit indirectly by their impact on the thirty year trends.
You can see this by looking at the rolling thirty year trend for the CMIP 5 ensemble mean. It initially falls to around the '67-'97 trend as the impact of the two major volcanoes in the tail end reduces the trend. After El Chichon enters the first half of the trend period, however, the trend rises to an initial peak in the '82-'12 as both volcanoes move closer to the start of the trend period. After El Chichon falls of the start, however, the trend rises, again until Pinatubo falls of the start of the trend period, at which stage the trend rapidly declines to the 2030-2050 (terminal year) mean trend of 0.23 C/decade. The timing in the changes of slope leave no doubt that those changes are the consequences of short term events on the 30 year trends.
In contrast, the observed trend (GISS) rises faster and earlier than the modelled trend, in large part due to the effects of El Chichon being largely scrubbed by an El Nino giving greater effect to the Agung eruption (1963), not to mention the large La Ninas in '74/'75. The observed trend then levels of and declines slightly as the Pinatubo erruption nears the center point (and hence minimum effect on the trend), and as the tail of the trend period enters into the period of successively weaker El Ninos and stronger La Ninas following 2005. Again the variations are short term effects.
Because they are short term effects, we can partially project the change of trend in the future. As Pinatubo moves further towards the start of the trend period, its effect on the trend will become stronger so that the observed trend will tend to rise. This will particularly be the case if the current run of increaslingly negative SOI states ends, and we return to "normal" conditions. Unlike the modelled trend, that peaks with the 1992-2022 trend, the observed trend will remain high after that as the recent strong La Ninas move to the start of the trend period, increasing the observed trend in the same way that they now decrease the observed trend.
Basing long term projections on these year to year changes in the thirty year trend is transparently a mugs game. If you want to check observed vs modelled trends, the only sensible approach is to compare the statistics across an extended period with a steady (ie, near linear) increase in forcing at as close as possible to current rates. For easily accessible data that means RCP 4.5 from about 1960-2050.
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johnthepainter at 08:08 AM on 3 April 2014Alarming new study makes today’s climate change more comparable to Earth’s worst mass extinction
I thought you should know that when you rest your cursor on PNAS it provides a definition of PNA: "Pacific-North American pattern" instead of "The Proceedings of the National Academy of Sciences of the United States of America."
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ranyl at 08:01 AM on 3 April 2014Honey, I mitigated climate change
"Ranyl, you say solar and wind are not sustainable, but implicit in the assumption is that energy required to make them must comes carbon sources. Not so - it can come from renewable sources too. The energy plans in MacKay cover all energy usage. You need carbon to make steel, because you use CO as the reducing agent, but if the only thing we used carbon for was making steel, then the environment is easily able to mop up the emissions."
Assuming all the parts of renewable technologies have a plentiful resource, not really sure about that from several metals etc, and there are always losses from corrosion (esp. Marine) and recycling so they can't be sustainable forever, but that is picking hairs, and yes if full recycling done and all energy from renewables to make them they might be able to be enclosed in a cradle to cradle like scenario for some time, so for you we can make as many as we like, power through despite the carbon costs to make enough to keep manufacturing them and that is higher than thought as for wind say that would need transforming all the steel furnaces to electric, cement kilns, for solar the solar panel factories (use gas at present), glass factories, all the factories that make all the chemicals for all the processes, so a large carbon cost to put this system in place but then we can adapt to whatever?
Or might we blow the carbon budget further and tip something that the IPCC is quite likely now.
"You seems to have dismissed solar CSP completely (no solar panels involved, only mirrors)."
No just have not mentioned them for the UK, as not really viable but yes in other places have a place, of course still have impacts, high grade mirrors are made of something special (what is the reflecting metal) and break, and the tower and the storage technique but could be lower in comparison to PV, but still quite large upfront carbon cost and that is what matters in global warming the total amount of carbon into the atmosphere at a time when we already have a dangerous debt not a budget.
My power down scenario also isn't a scenario and the arithmetic was put in carbon calculator. The 800Kwh/yr is actually for 2 of us as well and I work ~60% from home (included in that) and work in a low energy intensive organization, where I use as little energy as I can, so still not exactly much used. However that is me and as I say I am fortunate and have an easy life like this and I don't tell anyone to do anything that is up to them, I just say this is what I do and the reason why and that the reason I would go further is that we have no carbon to spend. We are witnessing one of the fastest rates of warming seen in the geological records and this time the world's ecosystems already on its knees (due to us) and reading the blog post today on mass extinctions this is worrying and further increases that carbon debt really and need to stop introducing anything ecosystem disrupting into the mix.
"The crunch about climate change is the speed. There isnt an optimum CO2 level, but change has to be slow enough that adaptation can take place. Anything that slows climate change will help. Of course, virtually nothing would be more effective than holding world population at current level or below."
Yes the speed is critical and the sulfur burn we'll get if we ever stop using fossil fuels or clean up the tailpipes properly will be significant, however the final degree C rise is totally dependent on the total amount of CO2 we put into the atmosphere, the more we put in the higher it goes, and yes the faster we put it in the quicker the temperature rises which as you say quite rightly does have further consequences, as the peak temp. rise is higher and that could push us past some more serious tipping point. As 350ppm means an equilibrium temp. of 3-5oC higher if the Pliocene records are reasonable estimates right then being at 400ppm does mean we have a huge carbon debt and no carbon to play with anymore. Therefore a carbon debt and an extinction rates at record levels even before warming gets really going and previous warming’s from mass CO2 releases like this have caused extensive ecosystem failures.
As for computer yes if the world expectations changed to not need CPU for almost everything and I could do a worthwhile job then yes I would be happy to give up on CPU, I am trapped in professional use at present but do use that job to try get as many people as possible to learn about the situation and to want to power down, to use low environmentally impacting energy provision techniques and rationalize that we have a carbon debt not a budget and thus no carbon to spend as such just a gamble that the amount extra we know put in won't shift the global mean temperature too far and that a further tipping point isn't induced.
Therefore my questions again to keep the CO2 gamble to a minimum and thus the temperature rise to a minimum are;
What is a safe peak and what is the 2100 goal?
How much carbon should we gamble on future energy provision set up?
How much carbon should we gamble on adaptation measures?
How much carbon should we gamble on building renovations and new builds?
How much carbon should be spend on moving large areas of Bangladesh, Florida (sea level rise doesn't care if your American or whatever), West Wales coastline?
Can you make electric helicopters to repair the offshore wind?
How much carbon should we invest in water security in terms of both supply and flooding protection?
How much carbon should we risk on health care security?
How much carbon should we gamble on totally changing the car fleet to electric vehicles?
What is safe here?
What are the risks?
What does 2oC mean in terms of extremes considering what we are getting already?
How hot is Australia again already, how many destructive heat waves, droughts and floods are they having again??? UK? Central Europe? China?
How much more carbon can we gamble just to keep the lights on? -
chriskoz at 07:36 AM on 3 April 20142014 SkS News Bulletin #2: IPCC Report (WG II)
Very interesting (and a bit disturbing IMO) development: FF company going after 16-year old April Foul prankster:
ASIC to look into prank Metgasco email from schoolgirl Kudra Falla-Ricketts
A warning to all activists. And as usual, shame on the greedy company. Especially in light of the last paragraph quoting University of Melbourne law expert Ian Ramsay, in whose opinion, the company should have considered the minority status of the offendant and speak to them rather than going after.
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scaddenp at 06:18 AM on 3 April 2014Climate Models Show Remarkable Agreement with Recent Surface Warming
Klapper, then perhaps you should comment on the article "It's the PDO" and update us with research on this matter.
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NewYorkJ at 02:17 AM on 3 April 20142014 SkS News Bulletin #2: IPCC Report (WG II)
New study on drought projections:
Benjamin I. Cook, Jason E. Smerdon, Richard Seager, Sloan Coats. Global warming and 21st century drying. Climate Dynamics, 2014;
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MA Rodger at 02:03 AM on 3 April 2014Global warming not slowing - it's speeding up
scaddenp @49.
If you perhaps restricted an Absolute Ocean Heat Content to thermal & latent energy, a figure for global oceans would be something like 1,000,000 ZJ (assuming the decimal point has behaved itself). That would be half to raise it to 0ºC and half to melt it. (I'm assuming the coefft of heat capacity at temperatures below -100ºC doesn't suddenly drop off more quickly.) There shouldn't be a lot more energy required than that. To raise a 100m mixed layer to an assumed average of 14ºC would be something like a trivial (wrt AOHC) 200 ZJ & I'd guestimate 40,000 ZJ for the rest of the ocean.
Tisdale's graph shows OHC rising from 110 ZJ to 170 ZJ and thus even for a daft-as-a-brush interpretation it has to be ΔOHC of some form. Likewise the graph at the head of the post that shows a pentadal rise of -90 ZJ to (guess what) +170 ZJ.
I'm finding the relevance to OHC of the equasion presented @43 which is for the average translational kinetic energy of a gas molicule (derevation here if you're interested) is a bit more difficult to nail down.
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pauls at 01:12 AM on 3 April 2014Alarming new study makes today’s climate change more comparable to Earth’s worst mass extinction
Surely this terrible study should be stopped immediately!
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CBDunkerson at 23:28 PM on 2 April 2014Cherry picked and misrepresented climate science undermines FiveThirtyEight brand
538 printed a rebuttal from Kerry Emanuel.
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Jim Hunt at 23:23 PM on 2 April 2014IPCC report warns of future climate change risks, but is spun by contrarians
ubrew12@3 - I'm not sure that this counts as "traditional organic agriculture" exactly, but you may also be interested to read about the awkwardly named (IMHO) "biochar". See e.g.
http://forum.arctic-sea-ice.net/index.php/topic,273.0.html
and the references therein. Perhaps surprisingly, I mentioned the concept to the scientific advisor to the National Farmers Union here in the UK, and he seemed quite keen on the idea, as long as the price was right!
http://econnexus.org/food-production-fears-over-devon-solar-farms/#comment-22732 -
Klapper at 23:06 PM on 2 April 2014Climate Models Show Remarkable Agreement with Recent Surface Warming
@scaddenp #40:
1. No. I think the main influence on trends, at least 30 years long is the state of AMO/PDO. On shorter trends, say 10 years, then yes ENSO has the dominant leverage.
2. No. I think the the PDO or some 60 year cycle based on AMO/PDO as identified by Swanson and Tsonis has very large influence over the warming/cooling rate of longer trends, i.e. 30 years.
3. Yes/No. Enso like behaviour shows up in some of the (better?) models, but we can't predict Enso more than about 6 months in advance. Some have tried to predict ENSO based on solar cycles, like the late Theodor Landscheidt. The PDO appears to switch on a 30 year period so I'm not sure I agree with your second point
4. Can't remember positive vs negative states, but I think yes I agree.
As for the Nino3.4 at 1.5 (as predicted recently for this fall/winter), I think it might give some monthly anomalies of +0.6 in early 2015.
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Klapper at 22:54 PM on 2 April 2014Climate Models Show Remarkable Agreement with Recent Surface Warming
@Tom Curtis #39:
"You then prove that that is the case be quoting an eight year trend"
I think you misunderstand. I was comparing the rolling 30 year trends over the last 8 years. Over the last 8 years the SAT and CMIP5 30 year trends have been diverging sharply. That is in contrast to the period 1965 to 2005 when the 30 year trends between SAT and the models were within much closer. The model vs. empirical warming rates were also very far apart in the 1935 to 1955 period and I've discussed that issue in the past on Skeptical Science.
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Tom Curtis at 14:39 PM on 2 April 2014Climate Models Show Remarkable Agreement with Recent Surface Warming
scaddenp @40, the most recent ensemble mean thirty year trend (Jan 1984-Dec 2013) for CMIP5 RCP 4.5 is 0.254 C /decade. In constrast, the mean thirty year trend for the ensemble from Jan 1961 to Dec 2013 is 0.187 C per decade. To Dec 2050 it is 0.222 C/decade. The cause of the unusually high trend is the occurence of the cooling effects of El Chichon and Pinatubo in the first half of the trend period, with no equivalent volcanism in the later half. So while a thirty year period is long enough so that typically volcanic influences will not influence the trend, that is not true of all thirty year periods.
The same can also be said about ENSO.
As it happens, the slope of the SOI over the period Jan, 1984 to Dec, 2013 is 0.287 per annum, or 0.042 standard deviations per annum. That works out at 1.26 standard deviations over the full period - an appreciable, though atypical, negative influence on the trend in global temperatures.
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scaddenp at 14:04 PM on 2 April 2014Global warming not slowing - it's speeding up
I am also rather intrigued as to how you would define the total heat content of anything as an absolute number.
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scaddenp at 13:55 PM on 2 April 2014Global warming not slowing - it's speeding up
Bruce, the graph was off Tisdale's blog, not from a published reference, so you would have to check with Tisdale to be absolutely sure. However, his data source can really only be NODC where their metadata explicitly state that it is delta from baseline. Furthermore, if you add NH + SH values, you will see that they range roughly 10 in 2005 to 16 in 2012 - the same values for the total OHC at those time periods shown in graph at the top of article. This graph does have a zero (and negative values), and paper it is based on say delta.
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scaddenp at 13:34 PM on 2 April 2014Climate Models Show Remarkable Agreement with Recent Surface Warming
Klapper, just a avoid pointless controversy, do you agree with the following:
1/ ENSO is the major cause of variation from trends in the absense of volcanoes.
2/ ENSO/PDO has little/no effect on 30 trends
3/ Models cannot predict ENSO and PDO
4/ A change to positive PDO will increase SAT
And a matter of interest, what is your estimate for what an El Nino of say 1.5 will be on SAT?
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BruceWilliams at 13:31 PM on 2 April 2014Global warming not slowing - it's speeding up
scaddenp@45
The graph Y axis is Joules, not delta Joules. And there are no zero point dates anywere on the graph. Also, the graph does not annotate that the values are change.
The heading on the Graph specifically says it is:
"NODC Annual Hemispheric Ocean Heat Content (0-2000 Meters)" which is an absolute value heading, not a change heading.
Based on all of this I would tend to disagree with you that the graph represents the change from a date range but rather is the total calculated energy content just as the heading says.
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BruceWilliams at 13:16 PM on 2 April 2014Global warming not slowing - it's speeding up
scaddenp@44
I understand your confusion. I meant to say energy content is simply 3/2 kT. And since the energy content doubled, the temperature doubled. Mathematically that would be E_k = 3kT/2 therefor T = 2E_k/(3k) and since 2,3, and k are constatnts, the E_k doubled so the temperature doubled.
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Tom Curtis at 13:12 PM on 2 April 2014Climate Models Show Remarkable Agreement with Recent Surface Warming
Klapper @37, I concluded my comment @36 by saying "... talk of warming rates in models "40 to 50%" to high just shows a lack of awareness of the stochastic nature of model prediction."
You then prove that that is the case be quoting an eight year trend. An eight years, I might add, that goes from neutral ENSO conditions to the strongest La Nina on record as measured by the SOI.
Just so you know how pointless it is to look at eight year trends to prognosticate the future (and hence to vet climate models), the Root Mean Squared Error of eight year trends relative to 30 year trends having the same central year is 0.17 (NOAA) with an r squared of 0.015 between the two series of successive trends. That is, there is almost no correlation between the two series, and the "average" difference between the two trends is very large. The mean of the actual differences is -0.04 C/decade, indicating that eight year trends tend to underestimate thirty year trends. The standard deviation is 0.17 C/decade, giving an error margin 1.7 times larger than the estimated 30 year trend. For HadCRUT4, those figures are -0.04 mean difference, and 0.18 C/decade standard deviation. Therefore, you are quoting a figure just one standard deviation away from the current 30 year trend, and well less than two standard deviations from the predicted trend from the models as proof of a problem with the models. The phrase "straining at gnats and swallowing camels" comes to mind.
And you still want to test models against a single period rather than test their performance across an array of periods as is required to test stochastical predictions!
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Non-Scientist at 12:35 PM on 2 April 2014Skeptical Science Widget Hacked
Dunno, maybe the hack has an angle.
Which of these is more urgent:
1. Save people living on overdeveloped, already sinking land Florida from invasive species, heat, fire and finally a watery doom.
OR
2. Relieve chronic sneezing from 100 billion helpless wittle kitties!!!
I rest my case.
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Jim Eager at 11:28 AM on 2 April 2014Skeptical Science Widget Hacked
Doh! We was pawned on fools day.
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