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Rob Honeycutt at 04:25 AM on 6 April 2014Earth has a fever, but the heat is sloshing into the oceans
Topal... "Overall, there is no change in the heat content, it's just redistribution and mixing of existing heat."
Your question was not in regards to changes in heat content. You asked about mixing and how heat gets distributed to lower layers.
If you're actually interested in ocean-atmosphere coupling here's a really great page that explains all the mechanisms in plain language.
http://eesc.columbia.edu/courses/ees/climate/lectures/o_atm.html
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Rob Honeycutt at 04:22 AM on 6 April 2014Earth has a fever, but the heat is sloshing into the oceans
Topal @6... Previously you asked the question, "What is the mechanism that pumps heat down without mixing it with the layers on the way down? What is the driver or this pump?"
The diagram I showed you @7 explains how it's not a matter of "mixing with the layers on the way down." It's a matter of shifting the thermocline, and the "driver" or "pump" the mechanism is surface winds.
If you understood this in the first place, I'm not clear on why you asked such a question.
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howardlee at 02:08 AM on 6 April 2014Alarming new study makes today’s climate change more comparable to Earth’s worst mass extinction
Tom - Ii think the climate sensitivity question goes to the heart of the issue. We have on the one hand sensitivities based mainly on modeling and the instrumental record that are 1.5-4.5°C (2.7-8.1°F) (IPCC AR5).
On the other hand, looking at the geological record, it suggests that actual Earth System Sensitivity is double that. For transient sensitivity - relevant to the year 2100 - we have to bridge the gap between what we are doing now to that long term sensitivity. Zeebe does this in this paper: "even if the fast-feedback sensitivity is no more than 3 K per
CO2 doubling, there will likely be additional long-term warming from slow climate feedbacks"Even though The AR5 study included the paleoclimate sensitivity in this paper i worry that by heavily weighting the study with benign glacial-interglacial changes which happen within the slow feeback timeframe, we may have generated an overly benign estimate of climate sensitivity. The carbon-belch scenario - with atmospheric emissions overwhelming the surface ocean and fast feebacks before deep oceans come into play would - intuitively - suggest a much higher sensitivity. That's why study of LIP-generated climate change could be crucial for understanding what's in store for us, more so than glacial-interglacial changes.
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One Planet Only Forever at 02:03 AM on 6 April 2014Earth has a fever, but the heat is sloshing into the oceans
A clarification of my comment @2.
Evaluation of global average surface temperature for time periods that are not long enough to average in the broad range of the significant influences like ENSO (phase and strength) and volcanic dust (amount, nature of the particles, and height and distribution in the atmosphere), can be performed by reasonably accounting for those influences.
The challenge is getting people who want to believe otherwise to stop choosing to focus on information in a way that suits their interest. Some people may never overcome their struggle to better understand what is going on because they won't give up their strong personal desire to get the most possible personal benefit any way they can get away with.
For the sake of the future of humanity (and all other life on this amazing planet), these people need to be disappointed by policy and actions regardless of the impression of popularity and profitability that can be created for the unacceptable unsustainable actions and attitudes they refuse to change their mind about. (That is delving into the politics, but I mention it because I consider it to be the best understanding of what is going on, which is an assessment of the available observations, which is what science is all about).
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sidd at 15:21 PM on 5 April 2014Earth has a fever, but the heat is sloshing into the oceans
there is actually a nice dichotomy to be explored herea)isotherm heaveb)water mass changethe first has a short time constant, on the order of montthe second perhaps decadesthis is explored in a fascinating paper by Purkey and Johnson dealing with the southern hemisphere DOI: 10.1175/JCLI-D-12-00834.1also i note that my previous comment is now a)redundant, since the comment previous to it has been removedb)self-referentialheeheeheesidd -
One Planet Only Forever at 12:53 PM on 5 April 2014Earth has a fever, but the heat is sloshing into the oceans
Topal,
A further clarification. El Nino conditions mean that the average surface temperature of the equatorial Pacific is warmer, La NIna means the overall average is cooler. The following link to the NOAA data of the ONI may help you better understand this. You can see that the variation of the average is significant (several degrees C)
http://www.cpc.ncep.noaa.gov/products/analysis_monitoring/ensostuff/ensoyears.shtml
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One Planet Only Forever at 12:48 PM on 5 April 2014Earth has a fever, but the heat is sloshing into the oceans
Topal,
Here is anopther version of the same thing others have been trying to help you better understand what is going on.
When La Nina conditions exist a large area of the eastern equatorial Pacific Ocean has cold surface waters upwelling as shown to you by ohers, and able to be learned about from a variety of sources if you really want to better understand what is going on. That colder surface is a circulation of the deeper colder waters and it takes heat out of the air above it (wind and wave action), leading to a global average surface rtemperature lower than a norm or avergae ENSO neutral temparature (because the winds result in the cooling affecting more area than just the cooler surface water region.
When El Nino conditions form the entire area of the equatorial Pacific is warmer leading to much warmer air being circulated around the planet and a higher than "norm or average" global average surface average temperature like the one created by the very strong El Nino of 1997/98 (a similarly strong El NIno has not formed since then, but one will)
I hope that helps.
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Tom Curtis at 11:11 AM on 5 April 2014Alarming new study makes today’s climate change more comparable to Earth’s worst mass extinction
howardlee @16, I agree with you about the ocean currents. With respect to the Permian taiga forest like conditions, that would be consistent with a forcing equivalent to modern forcings rather than with a forcing less than during the last glacial as suggested by the revised CO2 estimates. Having said that, that estimate assumes modern alebedo. Had the albedo decreased to 0.25, the net solar forcing would represent an increase of 11.5 W/m^2 rather than a decrease of 5.2 W/m^2. The unknowns are too large to say anything definitive.
I will say this, though. The forcing calculations show that a change in conditions equivalent to that which drove the Permian extinction event cannot be excluded based on "high" Permian CO2 levels; but nor is it certain that we face one. Based on Sherwood and Huber, we would require four doublings of CO2 at "likely" estimates of climate sensitivity to reach such conditions; but could reach them with two doublings at climate sensitivities within the IPCC "90% confidence interval". That is, a BAU approach with declining conventional fossil fuels being replaced by unconventional fossil fuels (shale oil, tar sands) and diesel manufactured from coal could bring about such conditions from, at a rough estimate, 150-300 years from now.
We could get Permian extinction levels of species loss, however, within 100 years with without such an aggressive BAU approach when coupled with other factors (notably overfishing).
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Tom Curtis at 10:43 AM on 5 April 2014Alarming new study makes today’s climate change more comparable to Earth’s worst mass extinction
chriskoz @12:
1) While local warming rates may not correlate with local forcings due to heat transfer, for increased insolation to not result in a greater warming at the tropics than at the poles, it must drive a mechanism to reduce the escape of heat to space, thereby forcing greater heat transfer towards the poles. In fact it does drive such a mechanism in the water vapour feedback. However, given that the WV feedback essentially doubles the Planck response to forcing, it is a reasonable approximation that for the same forcing, increased CO2 (which also restricts heat escape to space) will drive a greater heat transfer to the poles than will an equivalent increase in insolation. Indeed, given the same global temperature response from both forcings, and given that CO2 forcing does amplify polar temperatures more than does solar forcing, it follows that solar forcing must generate greater warming elsewhere for the average to come out the same.
2) While relative change from conditions to which organisms are adapted to is the major driver of extinction, there are some hard physiological limits. Clearly no organism can survive the permanent lowering of its body temperature much below freezing. The possibility of evolving some sort of antifreeze for the blood (found in some fish) or or merely seasonal activity makes this "hard limit" a bit fuzzy, but the dominance of warm blooded life forms in Arctic ecology shows that very low temperatures present more than a relative impediment to life.
The same occurs for warm temperatures. Very high temperatures restrict the capability of getting rid of excess heat. This is particularly a problem for large warm blooded creatures, but at higher temperatures becomes a problem for large "cold blooded" creatures, which generate internal heat from the function of muscles and organs, as well. For large warm blooded creatures that use evaporative cooling for heat dissipation, the "hard limit" is sustained wet bulb tempertures of 35 C (SkS summary).
Even for small cold blooded creatures, as sustained temperatures exceed 40-50 C, the disorganizing activity of the heat tends to overwhelm their ability to sustain life - but that limit is nowhere near as hard as it is for large cold blooded, or for warm blooded creatures.
3) While Burgess et al may not attribute the extinctions to high temperatures, Sun et al (2012), linked in the OP under "lethally hot" certainly do. They write:
"The entire Early Triassic record shows temperatures consistently in excess of modern equatorial annual SSTs. These results suggest that equatorial temperatures may have exceeded a tolerable threshold both in the oceans and on land. For C3 plants, photorespiration predominates over photosynthesis at temperatures in excess of 35°C, and few plants can survive temperatures persistently above 40°C. Similarly, for animals, temperatures in excess of 45°C cause protein damage that are only temporarily alleviated by heat-shock protein production. However, for most marine animals, the critical temperature is much lower, because metabolic oxygen demand increases with temperature while dissolved oxygen decreases. This causes hypoxaemia and the onset of anaerobic mitochondrial metabolism that is only sustainable for short periods. As a consequence, marine animals cannot long survive temperatures above 35°C, particularly those with a high performance and high oxygen demand, such as cephalopods."
The lower temperature for marine animals is because of induced anoxia rather than heat stress specifically, but for land animals and plants, it is heat stress that is the killer.
While Sun et al deal strictly with the Triassic, including the aftermath of the Permian/Triassic extinction, Burgess et al show that CO2 levels at the extinction event where higher even, than those at the end Smithian with its 40 C tropical waters. (As a side note, those 40 C waters may have been restricted to the proto-tethys, a very large shallow sea stradling the equator, and may not have been typical of oceanic tropical water.) As it happens, CO2 concentrations were higher during the Permian extinction than the end Smithian, with presumably higher temperatures as a result:
(Corrected version of Burgess et al, 2014 Fig 3)
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topal at 10:28 AM on 5 April 2014Earth has a fever, but the heat is sloshing into the oceans
Rob, I know how this works. But the warm water that accumulates to greater depths in the west results in colder water being exposed at the surface in the east. Overall, there is no change in the heat content, it's just redistribution and mixing of existing heat.
(snip)
Moderator Response:(Rob P) - No, you don't know how this works. Your line of questioning bears this out.
You appear uninterested in learning, which is my bad because I thought you were interested in learning a little bit about oceanography. Just don't plaster this site with your unsubstantiated opinions as you will find them moderated out - as above.
This is a site reliant on the scientific literature. There are plenty of other sites on the internet that would welcome your unsubstantiated inexpert opinions.
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Rob Honeycutt at 10:02 AM on 5 April 2014Earth has a fever, but the heat is sloshing into the oceans
Topal... Here's an illustration that's even more simple and easy to understand.
What you can see is that, it's not a matter of the heat going straight down through the ocean layers. It's about warmer waters being shifted.
In diagram (a) the upper layer is warmer than the lower layer. In diagram (b) the same amount of heat shows a cooling upper layer and warming lower layer.
[source]
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Tom Dayton at 08:38 AM on 5 April 2014Earth has a fever, but the heat is sloshing into the oceans
topal, NASA has a short explanation with pictures.
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topal at 08:23 AM on 5 April 2014Earth has a fever, but the heat is sloshing into the oceans
@RobP - "more heat has been pumped down into the ocean". What is the mechanism that pumps heat down without mixing it with the layers on the way down? What is the driver or this pump?
Moderator Response:(Rob P) - The driver of the 'pump' are the trade winds which result in the net transport of surface water (ocean currents) at right angles to the wind - to the right of motion in the North Hemisphere, and to the left in the Southern Hemisphere. By blowing toward the west, the trade winds 'push' surface water toward the poles. This divergence of surface water at the equator is why we have upwelling in the central and eastern equatorial Pacific Ocean.
The poleward surface currents out of the tropics collide (in the subtropical ocean gyres) with equatorward surface currents forced by westerly winds at mid-latitudes and, with nowhere else they can go, the currents are forced down into the ocean. Spin-up the wind-driven circulation and you get stronger upwelling at the equator and stronger downwelling in the subtropical gyres. Weaken the circulation and both upwelling and downwelling weaken too. With weak horizontal transport of surface water out of the tropics, the tropical ocean heats up anomalously.
This phenomenon largely exists because we live on a rapidly rotating planet. Vagn Walfrid Ekman realized the seemingly bizarre effects of rotation on the Earth's oceans back in 1905.
We do have some posts coming up on this topic, but I've been dragging my feet because the graphics and animations have to be created.
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topal at 07:10 AM on 5 April 2014Earth has a fever, but the heat is sloshing into the oceans
Is "sloshing in and out of" the oceans a newly found phenomenon or didi it already happen in the past? If so, when was the last time energy sloshed in and sloshed out and how was it measured? What deterimines the periodicity of this phenomenon? What are the physical mechanisms causing this energy transfer in and out, in other words: where does this energy come from and how is it transfered in and out?
Moderator Response:(Rob P) - multidecadal variations in the strength of the trade winds are responsible for this variation in the rate of ocean heat uptake, see this SkS post: Unprecedented trade wind strength is shifting global warming to the oceans, but for how much longer?.
Since about the year 2000 these trade winds have been much stronger than is typical over the past century. This means that the convergence of surface currents in the subtropical ocean gyres has been enhanced and therefore more heat has been pumped down into the ocean interior than is normal. This will dramatically weaken when the trade winds weaken and, based on some theories of this decadal variability, the intense trade winds have probably shortened the length of the current negative phase of the Interdecadal Pacific Oscillation (IPO).
The oceans will still warm during the positive phase of the IPO, because ocean warming is currently driven by the increased Greenhouse Effect, but the heat uptake should be reduced. Counterintuitively, surface warming will increase much faster - because less heat is being removed from the surface ocean down to deeper layers.
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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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