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Conventionalskepticist at 09:27 AM on 29 May 2016They changed the name from 'global warming' to 'climate change'
What of this?
https://w3.newsmax.com/NMWOS/media/Images/CTI/no_global_warning-bw.jpg
https://w3.newsmax.com/NMWOS/media/Images/CTI/nasa-satellite300-s.jpg
Moderator Response:[RH] Sorry. No link only posts. Please review commenting rules.
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michael sweet at 08:08 AM on 29 May 2016CO2 is not the only driver of climate
Tom,
I do not remember seeing Krakatoa used as an example against the "CO2 concentration is too low to make a difference" argument. I thought it was an excellent argument since it is weather and the concentration of SO2 is so much lower than CO2. Thanks for the new argument.
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DSL at 04:56 AM on 29 May 2016CO2 is not the only driver of climate
Billev, it's easy to see patterns. That, in fact, is the human brain's extraordinary strength. Critical thinking is a systematic way of testing the strength of apparent patterns. You're failing at critical thinking because you refuse--for no apparent reason--to accept that CO2 absorbs and emits radiation at various broadened bands within the thermal infrared range. That action--the central component of the greenhouse effect--has been established in lab for over a century, established through applications that rely on the effect's existence, and established through direct field measurement.
If atmospheric CO2 increases, the climate system will store more energy. Whatever alternative theory you propose, it must include that actually-verified component. If you refuse to include that component, then your theory is never going to describe the Earth climate system. It's like trying to explain human history without referring to economy. -
JIm Steele at 04:01 AM on 29 May 2016Corals are resilient to bleaching
Rob asserts, "tropics are reaching temperatures in summer that exceed the upper thermal tolerance threshold of coral that is no longer the case"
You are assuming that the upper thermal tolerance threshold has been reached but symbiont shuffling and shiftings has demonstrated that the upper threshold is moveable and new thresholds rapidly evolve. The fact that coral thrived during the Holocence Optimum when temperaturs in the Coral Sea were 2.1C warmer than today suggests you are very wrong about corals upper threshold. Coral must adjust their thermal boundaries to deal with cooler and warmer temperatures. The Great Barrier Reef Expedition of 1928-29 was concerned with bleaching and warming temperatures. Bleaching happens when ever there is an abrupt event that exceeds the prevailing climatology. If the extremes represent a trend the coral then evolve new symbiont partnerships best suited for that change.Most global bleaching events are temporary and will not be detected by cores sample. Furthermore as discussed in Hendy 2003 even massive mortality as observed in the 1998 El Nino bleachings are very difficult to detect without much much larger samples size within a location and from a wider range of locations.
You absurdly suggest a growing pace of coral death based on extrapolating from a short term snapshot and dismissal of the evidence of symbiont shifting. But most reefs that suffered high mortality have recovered within a decade and have been resilient to subsequent warm events. Bleaching is a minor cause of moratlity and coral have had to evolve resilience and quick recovery to deal with more destructive forces such as tropical storms.
Moderator Response:[Rob P] - Symbiont shuffling is no panacea for the ongoing global demise of coral reefs. It's just another example of people in denial building a delusional belief around a 'kernel of truth'. Yes, symbiont shuffling is a real adaptation, but no it won't save coral reefs. The current precipitous decline in global coral cover might be a wee bit of a giveaway here. A glaring example is the recent assessment of the 2016 bleaching event on the Great Barrier Reef (GBR) - there is an average of 35% mortality on the central and northern reefs surveyed, an area making up two thirds of the entire GBR reef system. So one single bleaching event may have eliminated 20% of the reef. Fat lot of good symbiont shuffling did after GBR bleaching events of 1998 & 2002 eh?
The Holocene Thermal Maximum is an interesting point. Was it warmer in the tropics during this interval? There doesn't seem to any consensus on this. The change in insolation due to orbital forcing would have made the tropics cooler-than-present, while outside the tropics, the Northern Hemisphere in particular, was much warmer. See the figure below from Marcott et al (2013) and note panel C) - the average annual insolation anomaly compared to modern-day.
Rosenthal et al (2013) show that intermediate waters were much warmer, but the reef-building coral we're talking about don't live hundreds of meters deep. How much of this high latitude water returned to the equator via the subtropical cells, and how much did it affect the surface layers? The authors reconstructions show a very modest SST cooling 0.5°C in the Indo-Pacific warm pool from 9000 years ago to present (present being 1950 as is convention). By constrast, Marcott et al (2013) reconstruct tropical temperatures as cooler-than-present at the Holocene Thermal Maximum.
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snedder at 02:43 AM on 29 May 2016In-depth: Experts assess the feasibility of ‘negative emissions’
It is very useful to have collected all these expert views in one place, thank you for that.
Would it be a fair summary to say that most of these expert opinions give very, very little grounds for optimism? The concensus seems to be that there are serious drawbacks to all the proposed methods for removing carbon dioxide emissions from the atmosphere. Either they are untried and uncertain to work; have only been tried on small scales and would require much R & D to prove whether they have any hope of working on the global scales required; or would only work if given massive resources (like huge areas of agricultural land being taken out of food production, and quite rapidly to boot).
It also seems that implementing anything on a scale that would make a difference would also require both an unprecedented degree of worldwide political concensus; and an unprecedented willingness of ordinary folk to pull together, accept perceived hardships (like dietary change or higher taxes), and not put short-term personal needs and desires before the long-term greater good. Are these things practicable?
It even seems doubtful whether more R & D is desirable. Holding out hope for upcoming negative emissions technologies may be seized on by political leaders; they would surely use it as an excuse for many more years of doing too little, too late towards the real and urgent goal of reducing mankind’s carbon emissions.
It is surely better to stop emitting so much CO2 pollution than to emit it and then try to get it back. But sadly it also seems doubtful if the world’s political institutions are capable of taking the required action.
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Ger at 02:21 AM on 29 May 2016In-depth: Experts assess the feasibility of ‘negative emissions’
Darn.... Just typed in a long reply to request of #8 and #9 only to find that there was a cache_miss, work gone.
http://www.aebiom.org/ for references for already available residues from wood, pulp & paper and rubber industries. Specificly the use of difficult to use biomass residues torrefaction of several biomass species and the sources/distribution of the resulting fuel by http://www.biomasstorrefaction.org/
Additional Arundo Donax has been research as possible fuel and bio-remidation crop in Australia by CSIRO and as an 5 year research program of the EU under Cordis: http://cordis.europa.eu/project/rcn/37456_en.html
For the Biomass Integrated Gasification Combined Cycle (BIG-CC) I have based my calculations on the data available from 3 IGCC power plants, 2 America (as in Cost and performance of fossil fuel power plants with CO2 capture and storage of Edward S. Rubin à , Chao Chen, Anand B. Rao) and Willem Alexander in Buggenum, Netherlands. I made those calculations for power plants in the SE-Asia region (particular Cambodia, fueled with Arundo Donax) with data from suppliers as Solarmax (gasturbines), Dahlmann(gasification).
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billev at 00:34 AM on 29 May 2016CO2 is not the only driver of climate
Has there ever been any testing to examine the relationship beween the temperatures measured by the official measuring sites and the surface temperature at those sites? It would seem to me that if the two changed proportionately then that would indicate that the surface temperature was the driver of that sites's measured temperature. If the relationship was not proportional than it would appear that something in the atmosphere influenced the site's measured temperature. As far as there being a continuation of the pause that began around 2002 and should continue until about 2032, if the experience since 1880 continues, we will have to wait and see. I am too old to bet. i won't be around to collect. If the temperature record does plainly show a level line of global mean air temperature for the period in question it apparently won't be "seen" by those who are dubious about my remarks. And by the way, I don't have a theory about trhe future. I merely state that the past record seems to indicate a pattern of rise and pause that, if it continues, will be repeated in the future.
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bozzza at 15:05 PM on 28 May 2016Donald Trump wants to build a wall – to save his golf course from global warming
Remember what Arnold Schwarzenegger said: "The people lead, ..Governments follow!"
The middle-class have their pizza and talking head circus.... None of us care! The kids were just an excuse to put money into bricks and mortar and play the, "I'm Brad Pitt and you're Elle MacPherson" , game of dressed up charades.
What is a critical-mass again?
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bozzza at 14:59 PM on 28 May 2016Donald Trump wants to build a wall – to save his golf course from global warming
Climate Change is bigger than Trump!
When he says market forces are a beautiful thing he is abrogating responsibility knowing that is how he wins the popular vote. It's not statesmanship, to be sure, but he's saying market forces and regulation from the greater world will force everyone's hand to price the externality that needs to be priced.
...it's not statesmanship but it is business!
The priority for America is to remain business savvy and retain some sort of middle-class dream otherwise they are in Anarchy and I think we all realise nobody wants that.
Hmnnn, I think I almost convinced myself he is doing what is right!
(...it is the human condition to abrogate responsibility I seem to be arguing!)
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chriskoz at 13:23 PM on 28 May 2016Donald Trump wants to build a wall – to save his golf course from global warming
The "Trump phenomenon" is not just a case of climate science (in fact scinece in general) ignorance, but the broad ignorance of any social, economic, ethical, political (you name it) rules our democratic society has developed. The rise of such presidential candidade (totally unfit for the job he applies for) from GOP, only testifies how far that party alienated themslves from their voters. Voters decided to push for such paranoid, preposterous candidate, because they dislike all GOP mainstream candidates. It does not bid well to GOP future.
But that is not the aspect to be discussed here in SkS. It would've been much better if "Trump phenomenon" in particular exposed the climate science denial in GOP. It looks like, given a strong denial among GOP leaders, a candidate even moderately accepting AGW had no chance there: only the total and open ignorant like Trump had.
If such preposterous & ignorant man became next president later this year, it would be a world disaster in many aspects, particularly in climate mitigation as he wants to effectively pull US out of Paris agreement. There is no doubt about him doing that, because in face of presures from his own party and FF industries, pulling out is the easiest thing to do for an ignorant man. Such presidency would indicate US voters escape to the irrational mumblings of a beauty pageant minder and political puppet show, in preference of facing their economic and environmental problems. I hope such disaster do not happen.
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Tom Curtis at 08:53 AM on 28 May 2016Donald Trump wants to build a wall – to save his golf course from global warming
Stranger @4, I do not expect Trump to move very far towards rational policies, for doing so will loose him the popular support he has. This remains a factor in his potential presidency if he wants to run a second term, and/or if he wants cooperation from a Republican dominated congress.
The Hitler comparison is certainly inapt because, firstly, he has no brown shirts. Secondly, and more importantly, the constitutional protections in the US are far stronger than those of the Weimar Republic. Even Hitler could not do in the modern US, what Hitler did in Germany in the 1930s.
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Tom Curtis at 08:46 AM on 28 May 2016CO2 is not the only driver of climate
billev @43:
"I also am of the opinion that once the current EL Nino ends then the pause will reassert itself and continue until about 2032. I base that opinion upon the pattern of previous temperature change since 1880."
Crucially for Billev, it is an untested opinion. It is only be not testing his opinion against data that he is able to retain it.
In fact, several people have already made proposals of a similar nature to Billev's claim that the pattern of temperature will repeat themselves. Specifically, Don Easterbrook has argued for a near repetition of the pattern; Akasofu has argued more abstractly that the temperature pattern is a gradually rising trend modulated by a sine function and short term variations; and Loehle and Scafetta have argued for a repeating, rising temperature pattern accelerated since 1970 by global warming. As the linked articles show, none of these projections of temperature based on a cyclical pattern have been successful.
Billev's own theory is indistinct. He clearly rejects any forcing effect from CO2, and so cannot accept Loehle and Scafetta's projection. He thinks the "cooling pattern" that he expects to repeat from 2000 onwards was evidenced in the "early 1940s" which does not align with the repetition from 1945 used by Easterbrook. It is possible that he accepts a view similar to Akasofu's, but he is not explicit enough to be sure. Regardless, neither a repetition of the 5 year running mean from 1940 (to match the early 1940s projection) or the Akasofu cyclical function matches the post 2000 temperature function:
Billev's theory is a bust - something he does not know because he never quantified it and checked it against the data. That is, he used feels to develop his theory, not reasoning, and certainly not scientific method.
As Billev seems to have dropped discussion of the role of CO2 as a climate forcing, his remaining thesis is not on topic in this thread. I would highly recommend that if he wants to defend his busted theory, discussion be moved to the theory that he thinks most closely resembles his (from the three links above), or failing that, to the general discussion of different projections here.
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michael sweet at 06:54 AM on 28 May 2016In-depth: Experts assess the feasibility of ‘negative emissions’
Ranyl,
Your reference is close to other analysis that I have seen. Unfortunately, they contradict what Ger claims. Immense amounts of land and technology that has not yet been developed. Very strong claims from backers of BECCS without data to support those claims.
It was especially depressing that the primary interest for current CCS is to recover more oil from old wellfields. That is obviously going backwards.
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Stranger8170 at 04:07 AM on 28 May 2016Donald Trump wants to build a wall – to save his golf course from global warming
I’ve followed Trump for years. When he came out as an advocate of the Birther meme I couldn’t imagine what he was up to. He went on to solidify his support among right wing working folks and the bigots within the Republican Party. Those folks have been voting Republican since Reagan who used all the dog whistles to cement their support.
Issues like AGW, immigration, gay rights and other culture issues have captured them and Donald Trump, I believe was able to feel their heart beat.
After decades those Republicans have come to realize that the Republican establishment has done nothing for them and Trump has cashed in.
If you’re familiar with the old Trump you know he’s proposed things in the past like a onetime wealth tax and increased taxes on the rich. He was always prochoice.
We’ve seen recently that he’s now starting to once again rearrange his beliefs. His campaign positions he now claims “were just suggestions.” All the red meat he’s been feeding to right wing conservatives has gotten him enough now to be the Republican standard bearer. My guess, and I may be wrong, is he doesn’t believe any of what he’s been espousing.
I don’t want to make the Hitler comparison. I don’t think Trumps a Hitler but in the 1930’s he ran as a family values guy who claimed to be anti-abortion and a socialist and of course he was neither. He was going to make Germany great again. We know that what he was a demagogue who had his own agenda.
I won’t predict but I wouldn’t be surprised if Trump starts to reposition himself on issues like AGW. His pedigree is the antithesis of people he’s now in league with. -
JIm Steele at 01:59 AM on 28 May 2016Corals are resilient to bleaching
Rob, You put words in my mouth. I never made "the flawed assumption that the marine revolution that occurred during this time, as it pertains to coral reefs, came about because of some hitherto unrecognized invulnerability to warm water." I asked "Do you really want to argue coral suffered more from warmth than they have from the cold during the most recent ice ages??" and you went off on a strawman tangent.
The coral holobiont is constantly shifting the symbionts to maximize growth withing very narrow limits. Thus they are always stressed by an extreme El Nino event, whether happens in cooler water of the 1800s or warmer waters of the 21st century. Bleaching is part of their ongoing adpatation mechanism of expelling symbionts and acquiring new ones. This very well documented.
Obviously you and others disagree with those experts that push the adaptive bleaching hypothesis. That why it is a professional debate. That polyps die is by no means a refutation of that hypothesis and such an argument is a bit disingenuous. A colony consists of 100s to millions of polyp clones. Most of the clones die after a stressful event, such as an abrupt cooling or warming. It's like leaves falling from a tree but buds, or in this case cryptic polyps reamain viable and in what is known as the Phoenix effect those clones with a better adapted symbiotic partnership can rapidly re-sheet the skeletal remains. Recovery can take weeks or years, and the reefs with the greatest moratliy, 90% or more, have recovered within 15 years. In the process those living polyps have been demonstrated to acquire better adapted symbionts. And the species that experienced the most bleaching during on EL Nino are observed to rsist bleaching during subsequent extreme events.However because EL Nino warm event are abrupt and temporary, coral will again shuffle and shift symbionts to be better adapted to the cooler pre El Nino events. They may then re-acquire the old symbionts and once again be vulnerable to a EL NIno. The coral that suffer the most are exposed to extreme variability as warm EL Nino waters are replaced by cold upwelled La Nina waters. That' s why the cool eastern Pacific has only ~18 species, while the Western Warm pool has over 500 species and more massive reefs.
Fears surrounding bleaching and climate change are only valid if you believe that coral have reached their upper thermal limit and can only adapt via a slow evolutionary process. But there is amples and growing evidence that is not the case. Symbiont shifting and shuffling allows rapid adaptations, and there is no reason to believe that holobionts that thrived during the Holocene Optimum when tropical oceans were 2.1 C warmer than today, will not be able to thrive any similar warming over the next millennium
Moderator Response:[Rob P] Warming of tropical waters from the last ice age to the present has been beneficial to coral reefs, but now that the tropics are reaching temperatures in summer that exceed the upper thermal tolerance threshold of coral that is no longer the case. This is why coral cores show no evidence of mass bleaching, on the scale we are currently witnessing, in the last thousand years or so until the latter part of the 20th century.
Again the 'big picture' is the crucial point here. Bruno & Selig (2007) found that coral cover is declining at the rate of 1-2% per year irrespective of local conditions and Death et al (2012) discovered that half the coral on the Great Barrier Reef (GBR) has disappeared in the last 27 years. Only 10% of the GBR decline was attributed to bleaching mortality, which is a huge concern because the GBR has experienced a hiatus in bleaching due to the negative (La Nina-dominant) phase of the Interdecadal Pacific Oscillation (IPO). Continued ocean warming and a switch to the positive (El Nino-dominant) phase of the IPO suggests bleaching is going to become the major detriment to global reef cover over the next decade.When coral reefs globally are dying out at such an alarming rate, and when the oceans are warming and acidifying, it is absurd to offer a few limited exceptions as a counter argument. As time marches on, this global decline in coral cover will undoubtedly gather pace.
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SirCharles at 22:27 PM on 27 May 2016Donald Trump wants to build a wall – to save his golf course from global warming
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ranyl at 16:23 PM on 27 May 2016In-depth: Experts assess the feasibility of ‘negative emissions’
Ger,
http://www.biofuelwatch.org.uk/files/BECCS-report.pdf
Paints a very different picture to you.
Now you say very little extra land, but RSPB chap above says half of land on earth he wasn't thining about getting back to 350ppm or the re-release of carbon from the sinks.
Seems we have another scenario of don't worry cos technology can over come anything.
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scaddenp at 14:40 PM on 27 May 2016Ivar Giaever - Nobel Winning Physicist and Climate Pseudoscientist
It's called "going Emeritus". Many, many examples.
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nigelj at 14:29 PM on 27 May 2016Donald Trump wants to build a wall – to save his golf course from global warming
DrivingBy @1.
I couldn't disagree more. You say not to be worried about Trump, then basically imply we should put our faith in Trumps personal decision on climate change, or he will just wave like the breeze and go with public opinion! Surely those are both good reasons to be worried? In order not to be worried, we need to see a Presidential candidate that accepts the overwhelming scientific consensus and we need to see it now, not wait for him to possibly get there eventually.
You correctly note that Trump seems to have no bottom line beliefs except his own self promotion. Surely this is another reason to be worried?
You say 5 degrees will be very uncomfortable for a short blip of history but the world will go on. There's not much comfort in this.
Nobody is trying to force wisdom. We have instead got to do all we can to convince people and raise awareness. This is a different thing from forcing anyone.
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AnnieLaurieBurke at 13:21 PM on 27 May 2016Ivar Giaever - Nobel Winning Physicist and Climate Pseudoscientist
It seems that climate change denialism is one of the few fields where prominent scientists are accepted as credible, even when they have no climate expertise. Another physics Nobel laureate, William Shockley, began to express unfounded, racist views late in his career, and was condemned as having no expertise to support his views, despite his obvious brilliance as a physicist. So why are physicists, geologists, or even folks with PhDs in the liberal arts taken seriously as climate scientists, just because they have an advanced degree or an award that in no way relates to climate science? Could it be that they are celebrated and publicized by prominent deniers?
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DrivingBy at 12:50 PM on 27 May 2016Donald Trump wants to build a wall – to save his golf course from global warming
I think there's less cause for panic than the author states. Mr. Trump appears to have no fixed beliefs, other than in publicity and public image. He was a Democrat for longer than he's been a Republican, and has flop-flipped on virtually every issue. The one view he's never espoused is that of the Gramsci school: "Western civilization +/or the USA is the Great Satan of modern times".
If he's convinced that CC is bad for the USA and/or that >50% of the public demands it, he'll be all in for dealing with climate change. If the public is not amenable, he'll declare it's a hoax. At the moment, he's treating it as a culture wars issue. Since most people dislike science and form their opinions about scientific issues based on emotion, he may have a practical strategy.
I believe the way to succeed in promoting wisdom about climate change is to stick with the science, and let the political circus play itself out with only short, pointed and factual input for the scientific community.
If the world decides to roll the dice and see what 5 degrees brings about, it may be very uncomfortable for hominids for a short blip in history, but the Earth will take little notice and over a mere few thousand years will recycle the atmospheric carbon toward abyssal depths. Lets hope wisdom prevails instead, but it can't be forced.
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scaddenp at 11:02 AM on 27 May 2016CO2 is not the only driver of climate
So you agree that a very small amount of something can make a big difference after all. Want to try understanding why small increases in CO2 combine with other things to have a big effect as well?
" I also am of the opinion that once the current EL Nino ends then the pause will reassert itself and continue until about 2032. I base that opinion upon the pattern of previous temperature change since 1880."
Wow, that is bold assertion from someone refusing to understand physics. Still believing in the imaginary undetectable natural forces. I could do with some extra towards retirement saving. How much are you willing to bet on that?
"The current attempts to steer public opinion about man-made warming usually refer to the temperature records published by NOAA and GISS."
Clearly you have not actually read the IPCC reports. The surface record is important because we live on that surface. However, it is also very noisy because a small amount of energy exchange between ocean and atmosphere make a big difference to surface temperature. These are also unpredictable, though short in duration, and fool people into seeing patterns that dont exist if you bother to use something other than eyeball to analyze. The Ocean Heat Content does not have this problem and so is a better diagnostic of heat build up. Show me your cycle in that record. Show me any indication that build of CO2 has not continued to heat ocean. Do tell me where this energy in the ocean is coming from if not from anthropogenic.
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michael sweet at 10:28 AM on 27 May 2016In-depth: Experts assess the feasibility of ‘negative emissions’
Ger:
Can you provide links to support your claims? I wish that they are true but would like to see peer reviewed data.
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billev at 10:01 AM on 27 May 2016CO2 is not the only driver of climate
Because "the something else"(sulphur dioxide) combined with moisture to form long- lived high altitude clouds which screened the Earth from the Sun's rays and caused cooler temperatures. My steel sheet comments were in answer to the comments that pointed out how various small quantities could be effective, My point is that not all small quantities are effective. The current attempts to steer public opinion about man-made warming usually refer to the temperature records published by NOAA and GISS. My statement about the pause starting about 2002 is based on how I interpret those published records. I might add that I am not alone in that interpretation. I also am of the opinion that once the current EL Nino ends then the pause will reassert itself and continue until about 2032. I base that opinion upon the pattern of previous temperature change since 1880.
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Digby Scorgie at 09:17 AM on 27 May 2016Tracking the 2°C Limit - April 2016
On the main graph I rather miss those little marks on the horizontal axis that indicate the precise position of the relevant parameter — in this case years. There's a name for them, but I'm damned if I can remember it.
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hank at 06:59 AM on 27 May 2016In-depth: Experts assess the feasibility of ‘negative emissions’
Someone should lay out a comprehensive set of scenarios — for example if we laid off stripmining the ocean, let the top predators reestablish, and got the predictable recovery of the rest of the trophic cascade — that would maintain and improve a carbon sink that's currently just starting toward being destroyed.
Yeah. those lovely maps of seamounts never known until the satellite era are a guidebook for the illegal trawling that destroys them.Yeah, we used to have top trophic predators abounding. Whales, cod, tuna, sharks. Burp. They were good, weren't they? While they lasted.
They'd recover, if we got our grubby hands off the oceans.
So which countries navies are going to sign up to help with Sea Shepherd?
.... crickets ....
Then there's topsoil, and grasslands, and the herd grazers that used to maintain them. Anyone?Or failing that there's the screwfly solution.
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Ger at 01:31 AM on 27 May 2016In-depth: Experts assess the feasibility of ‘negative emissions’
Ranyl @#1:
Decrease in efficiency: suprissingly little, around a 3%. Gasification of biomass delivers a higher volume stream of lower BTU gas, increasing the efficiency of turbines. Cooling of the syngas gas stream delivers extra steam, to an amount of 5% extra steam and capturing CO2 at the exit of the gas cleaning with a watershift installation (CO+H2O -> CO2 + H2) is easier than from flue-gas. Biomass has less Sulphur, much less, so cleaning of Sulphur isn't as expensive as in an coal gasification plant.
How much land... Hardly anything extra, preferably a biomass which can grow on depleted land, waste land. Types like Arundo Donax, Cogon or other cover grasses to prevent eroding the land and in the vicinity of the power plant (as back-up fuel if import of MSW or bio-fuels is disrupted). If not needed, let your back-up grow an develop to a nice woodland like area. 'Simple' cover grasses can be harvested at least once a year.
Supringsly little power down.. No need if one increase efficiency by re-using heat for industrial purposes (e.g. torrefact MSW), nearby food mills or bio-fuel production (ethanol distilation) and replace the old fossil coal burners of 34% eff. with something with an average eff. of 55%.
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Ger at 01:01 AM on 27 May 2016In-depth: Experts assess the feasibility of ‘negative emissions’
To add to #4 Tom Curtis:
Torrefaction (slow pyrolysis) and bio-oil production (fast pyrolysis) are production ready. Input for both processes can be all types of (preferably less than 20% wet, self sustainable process) biomass delivering a bio-coal which can be applied as replacement for coal with far less CO2/kWh than fossil coal. Applied as fuel in an integrated Gasification Combined Cycle plant less than half the CO2 as with coal. Also, as produced from agri-residues, delivers a fuel for locals, a smokeless fuel, far better than firewood. Better as in less CO2/kWh and no smoke.
If plans are going as expected in the SE-Asia region, there will be an annual production of 300,000 tpa starting in Q1 2017, growing to a 1,000,000 tpa in 2019 with an calculate CO2 storage of 22.4% of the production.
Countries in the ASEAN area have capabilities of exporting a 50,000,000 tons of this biocoal from several sources capturing a 11.7 million tons of CO2. Just a tiny bit, but if that can prevent the burning of forest to make way for food production, quite an extra bit can be saved from being emitted.
If the same torrefation is applied on MSW (less efficient) with a bit of imported bio-coal for producing stocks of fuel instead of rotting heaps (so far still allowed) in landfills, more is to be gained.
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Tom Curtis at 00:09 AM on 27 May 2016In-depth: Experts assess the feasibility of ‘negative emissions’
SirCharles @2, at one point (3:00 forward) the video you show asserts that "no such [CO2 sequestration] technology exists" with regard to biomass, biochar and (presumably) other technologies such as carbon capture and storage. This assertion is the basis of "survivable IPCC projections" are "science fiction". It is also egregiously false. One would have to suspect, deliberately so. Biochar technologies, for instance, have been extensivly explored, and the base technology (charcoal) has existed on Earth for over a thousand years. Biochar technologies may not yet been proven to be commercial or scalable to the extent required, but that is because they are in early development. The same could also be asserted with equal truth of solar power, or wind power. Like biochar, these are technologies still being developed and which look to be both commercial without subsidies and massively scalable within a decade or so. Again, the same can be said of biochar. The video does not, however, assert that the biochar technology is not yet proven, or commercial. It asserts that it does not exist, thereby showing the video to be propoganda, not commentary.
This is even more the case with the assertion that "no such technology as" biomass, ie, the growing of plants, actually exits.
Equally troubling is the description of only RCP 4.5 and 2.6 as "survivable". No RCP pathway represents an existential threat to humanity, although RCP 6 and RCP 8.5 will result in a massive economic challenge and a very large number of deaths through disease and natural disasters. Describing only the lowest two pathways as "survivable" represents a gross alarmism which is as intellectually respectable as the denialism that asserts that RCP 8 is essentially without risk.
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denisaf at 22:46 PM on 26 May 2016In-depth: Experts assess the feasibility of ‘negative emissions’
It is quite clear that even the best of the practical measures to capture emissions will do no more that slow the rate of increase in concentration level in the atmoshere and absorption in the oceans. Whilst these measures should be employed, focus should also be on measures to adapt to the impact of the irreversible rapid climate disruption and ocean acidification and warming. The measures being implemented in the Netherlands, London and New York to cope with sea level rise and storm surges are sound examples of adaption measures.
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SirCharles at 22:16 PM on 26 May 2016In-depth: Experts assess the feasibility of ‘negative emissions’
The IPCC's 'Representative Concentration Pathways' are based on fantasy technology that must draw massive volumes of CO2 out of the atmosphere late this century, writes Nick Breeze - an unjustified hope that conceals a very bleak future for Earth, and humanity.
=> Survivable IPCC projections are based on science fiction - the reality is much worse
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MA Rodger at 19:28 PM on 26 May 20162016 SkS Weekly News Roundup #21
ubrew12 @5,
I think it worth adding a couple of points or so.
Firstly, the NOAA/ESRL Annual Greenhouse Gas Index is looking at the atmospheric content not emissions. So the trends in their numbers will be affected by natural pertubations. I think this results in an exaggerated rise, an additional acceleration, over the last couple of decades since 1990 or 2000.
Secondly, if we do accept that acceleration in the AGGI numbers continues, it woud suggest the 2xCO2(e) level arrives in 20 years. But note, as well as being exaggerated by natural events, that underlying acceleration also assumes we continue to grow FF use as we did since 1990 or 2000. I don't see that happening.
Thirdly, I agree that CO2 is the true devil because a significant proportion of it it will be with us for millenia. (It's likely destination will surely be our decendents using their technology to remove it rather than allow it to, for instance, send Greenland into melt-down.) Yet, I feel there is the potential for tackling SO2 emissions without tackling the positive forcings. Turning off coal-use or more effective/widespread scrubbing could easily see SO2 emissions massively reduced. Indeed the current trends are down. Sadly this is not so for the big GHGs.
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ubrew12 at 11:45 AM on 26 May 20162016 SkS Weekly News Roundup #21
Tom Curtis@4: That sounds reasonable. The reason to exclude nonCO2-GHG's in an 'equilibrium climate sensitivity' calculation is their relative impermanence once 'action is taken'. But that liability turns into an asset for sun-shading aerosol pollutants, since it is now their shading capability that is impermanent, not IR blocking. So we should follow CO2 alone for an idea of future IR blocking-induced heating, but understand that once aerosols rain out an additional heating will incur.
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ranyl at 09:02 AM on 26 May 2016In-depth: Experts assess the feasibility of ‘negative emissions’
Ta,
Some questions came to mind.
Do the scenarios with BECCS take in account the increased amount of biomass needed due to the drop in efficiency of power stations with carbon capture?
How much land will be needed to grow enough biomass for BECCS to sequester a 10ppm atmopheric drop, which is equivalent to ~20ppm in real terms for as CO2 drops the sinks re-release the carbon they sequestered as CO2 levels rose?
If 350ppm was the goal, then considering CO2e at ~480ppm, then that means ~260ppm of CO2 equivalence will have to be sequestered by 2100 to reach that goal.
With that amount of carbon involved, ~100years of current emissions, and considering all the additional emissions to come from forest fires, melting permafrosts and biodiversity losses, adding in the need for additional land use for more food (due to population rise and increasing diet ambundance), is there enough land for BECCS (if actually carbon negative when all things considered, especially if you change land use) to make a real impact?
Surprising how little massively powering down is mentioned, for even if BECCS is carbon negative to a degree is it as carbon negative as leaving the forest standing?
Mind you massively powering is not popular in general terms even if it would make things like ecosystem regeneration easier to acheive.
Wonder if BECCS could be intergrated into an ecosystem regenerating carbon sequestering system of land use like multiple species coppiced natural woodlands with paths and rides?
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scaddenp at 07:31 AM on 26 May 2016CO2 is not the only driver of climate
Actually I am starting to think billev is just trolling. He has so absolutely refused to look at the OHC record despite it being a better measure of global warming that surface temperature. Now why would that be? Tom has pointed out his outrageous claim that Kraktoa comparison is invalid. (If 400ppm of CO2 is "too insignificant to affect climate", then how come 3.9ppm of something else can?). He keeps going on about thickness of steel as if this was somehow relevant. (We can calculate whether given thickness of steel could stop a bullet just as we can calculate effect of 3w/m2 of extra radiation). If he is just here to have amuse himself at our expense, then I suggest "Do Not Feed The Troll."
The obvious alternative is that he has a cognitive bias against AGW from either ideology or group identity that prevents him comprehending any contrary fact, which also means we are wasting our time in trying to educate.
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DSL at 07:16 AM on 26 May 2016CO2 is not the only driver of climate
billev: "What then caused the, "on schedule" beginning of another pause shortly after 2000?"
What pause? It's already been pointed out to you that most (90%+) of the accumulating energy is being stored in the oceans, and much less (3-5%). is being stored in the atmosphere. Why would you base your arguments about warming on such a small sample of the climate system? This is akin to reviewing a restaurant after having had a bite of appetizer and a drink of tap water. Ocean warming shows no "pause."
Further, you do realize that the greenhouse effect has been directly observed, yes? Surface-based instruments have measured down-welling longwave radiation from the atmosphere for a while now. So you can make baseless claims about the greenhouse effect not being real, but you're simply wasting time. -
Tom Curtis at 05:11 AM on 26 May 2016CO2 is not the only driver of climate
billev @39:
"First, the Krakatoa example is not a good one. There is no comparison between the effect of the current level of CO2 and the effect caused by the gas and ash disgorged by the eruption of Krakatoa."
Argument by assertion is likewise an example of irrationality masquerading as rationality. It is also an example of 'sloganeering', as defined and prohibited in the comments policy.
As the argument stands, you have supported your argument from incredulity by an analogy (bullet and steel sheet) but merely assert that the analogy applies with respect to CO2 increases, but does not apply to the much smaller (as measured by parts per million by mass) injection of SO2 into the atmosphere by Krakatoa.
Perhaps you should support your claim by some basic facts, such as:
A) The preindustrial CO2 level raised the Global Mean Surface Temperature (GMST) by approximately 33 C (12.8%) relative to what it would have been in the absence of CO2.
B) CO2 levels have risen by 43% since the the preindustrial.
C) Therefore it is obvious because very thin sheets of steel will not stop a bullet that the increase in CO2 could not have had any effect on GMST.
I can then introduce you to the idea of a non-sequitur.
More seriously, as this example argument demonstrates, you rigourously refuse to quanitify your argument because any such quantification (if not ridiculous based on known facts) will show your argument to be an absurdity. Instead you rely on arguments from incredulity, from assertion, and from unjustified analogies. Specifically to your analogy, you have not shown that the preindustrial CO2 concentration has no effect, so that it is analogous to a steel thickness which has no effect.
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Tom Curtis at 04:52 AM on 26 May 20162016 SkS Weekly News Roundup #21
ubrew12 @1&3, if you wish to determine the effect of human activities on climate, you should include all effects including the cooling effects of aerosols and albedo changes for LUC. Doing so shows a total current anthropogenic forcing of about 2.1 W/m^2, not the 3.1 obtained by looking at WMGHG alone as you are doing. What is more, as is apparent on this graph, the forcing is rising steadily, not accelerating:
You may think that is unreasonable in that the aerosol effects will wash out of the atmosphere fairly rapidly in the event that we cease anthropogenic emissions (which is correct), but equally, if we cease anthropogenic emissions non-CO2 well mixed GHG will rapidly decompose, and CO2 will be fairly rapidly be taken up by the ocean until ocean/atmosphere equilibrium is reached. The upshot is that the long term climate effects are best determined by considering CO2 alone, and allowing for the effects of the CO2 cycle. For the short term effects, however, there is no substitute for looking at all forcings, including the negative anthropogenic forcings.
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billev at 04:19 AM on 26 May 2016CO2 is not the only driver of climate
I will try to address the several statements directed to me. First, the Krakatoa example is not a good one. There is no comparison between the effect of the current level of CO2 and the effect caused by the gas and ash disgorged by the eruption of Krakatoa. The graph showing the relationship between various forcings and the temperature record causes me to wonder why these forcings would follow such a reasonably precise 30 year pattern. I would not think a continually increasing presence of CO2 would follow such a timed pattern. If opposed forcings caused the pauses in warming then, again, why such a patterned occurence? One earlier post informed me that the warming pause in the 1950's and 1960's was caused by the presence of aerosols What then caused the, "on schedule" beginning of another pause shortly after 2000? As far as the argument that small amounts can be effective I say that that is not always the case. A one inch thick sheet of steel can stop a small arms bullet but a 1/2500th of an inch thick sheet of steel cannot. If a person cannot detect a rather precise pattern of warming and pause in warming in the Global temperature record starting in 1880 I can only say that to me the pattern is obvious. Whether it will continue in the ensuing years who can say. But I do believe that more attention should be paid to that distinct possibility. It would seem to offer a better prediction of future temperatures than most of the computer models have done.
Moderator Response:[RH] Note that your comment here has a complete lack of supporting evidence or citations of any research in support of your position. We expect a little bit more from commenters on SkS than most other websites. You're more than welcome to argue your position but you're currently skating along a thin line of sloganeering. If you wish to retain your commenting privileges you're going to have to up your game a few notches.
Alternatively, if you're here to try to learn something new about these issues, please acknowledge that you don't understand the science and other commenters who are knowledgeable will be more than happy to supply you with information, along with the requisite citations to review.
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ubrew12 at 01:50 AM on 26 May 20162016 SkS Weekly News Roundup #21
Thanks for responding. However, at around 1850, CO2 and CO2+nonCO2-GHG's are at the same Pre-Industrial value: 280ppm. Which value applies today? CO2 or CO2+nonCO2-GHG's? I'm sure the Infrared Radiation doesn't discriminate: the latter applies to climate sensitivity calculations. Hence, 560ppm within 10-20 years. Here's the relevant graph from the article:
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barry1487 at 20:40 PM on 25 May 2016Climate denial arguments fail a blind test
Australia has a small population so any measures to reduce greenhouse gas emissions will have insignificant impact
Same goes for many countries. Collectively, a bigger impact. If every country dropped out of mitigating CO2 emissions on the same argument... so see it as a collective issue, not nationally self-serving. Atmospheric CO2 is borderless.
It would be better if the focus was on issues to cope wth the consequences of climate change
Why not focus on both? Reducing emissions means less to deal with later on.
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bozzza at 19:47 PM on 25 May 20162016 SkS Weekly News Roundup #21
No, those numbers only apply to carbon emissions !
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denisaf at 17:19 PM on 25 May 2016Climate denial arguments fail a blind test
Denial of the occurrence of irreversible rapid climate change and ocean acidification and warming just shows lack of understanding of physical principles and the available evidence. Denialists, of course, often have vested interests that inhibits their seeking to gain understanding. For example, here in Australia, we have politicians who are denialists, presumedly because they believe that it will get them votes.
Another issue is what measures should be implemented to cope with the situation as best as physically possible. Australia has a small population so any measures to reduce greenhouse gas emissions will have insignificant impact, despite policies to encourage solar and wind systems. It would be better if the focus was on issues to cope wth the consequences of climate change, such as sea level rise.
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Bob Loblaw at 11:34 AM on 25 May 2016CO2 is not the only driver of climate
billev:
Your first sentence falls into the myth "CO2 is just a trace gas". (Follow the link to see why that is wrong. Same link that scaddenp posted.)
There seems to be quite a bit that you just "can't believe". It's not a strong argument. (It's not an argument at all, as Tom points out in his last paragraph.) If all you can do is keep saying you can't believe stuff or don't see proof, then you'll soon get moderated out for repetition.
[And I'll bow out, for now, to avoid the policy against dog-piling.]
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Jim Eager at 08:50 AM on 25 May 2016Climate denial arguments fail a blind test
"Remove the political context and just deal with numbers."
Snort! Good one there Barry.
Never mind that AGW dinial is all about politics, not numbers.
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Tom Curtis at 07:39 AM on 25 May 2016CO2 is not the only driver of climate
billev @35, the dry mass of the atmosphere is 5.352 x 10^18 kg. In 1883, Krakatoa errupted, ejecting 2 x10^10kg, or 3.7 parts per 1000 million of sulfur into the atmosphere. That became the dominant change of effect on climate for the subesequent few years, reducing global mean surface summer temperature by 1.2 C in the following year. The effects of the erruption are described by wikipedia, saying:
"Global climate
In the year following the eruption, average Northern Hemisphere summer temperatures fell by as much as 1.2 °C (2.2 °F).[10] Weather patterns continued to be chaotic for years, and temperatures did not return to normal until 1888. The record rainfall that hit Southern California during the “water year” from July 1883 to June 1884 – Los Angeles received 38.18 inches (969.8 mm) and San Diego 25.97 inches (659.6 mm) – has been attributed to the Krakatoa eruption. There was no El Niño during that period as is normal when heavy rain occurs in Southern California, but many scientists doubt that there is a causal relationship.The eruption injected an unusually large amount of sulfur dioxide (SO2) gas high into the stratosphere, which was subsequently transported by high-level winds all over the planet. This led to a global increase in sulfuric acid (H2SO4) concentration in high-level cirrus clouds. The resulting increase in cloud reflectivity (or albedo) would reflect more incoming light from the sun than usual, and cool the entire planet until the suspended sulfur fell to the ground as acid precipitation.
Global optical effects
The eruption darkened the sky worldwide for years afterwards, and produced spectacular sunsets throughout the world for many months. British artist William Ashcroft made thousands of colour sketches of the red sunsets halfway around the world from Krakatoa in the years after the eruption. The ash caused "such vivid red sunsets that fire engines were called out in New York, Poughkeepsie, and New Haven to quench the apparent conflagration." This eruption also produced a Bishop's Ring around the sun by day, and a volcanic purple light at twilight.In 2004, an astronomer proposed the idea that the blood-red sky shown in Edvard Munch's famous 1893 painting The Scream is also an accurate depiction of the sky over Norway after the eruption.
Weather watchers of the time tracked and mapped the effects on the sky. They labeled the phenomenon the "equatorial smoke stream". This was the first identification of what is known today as the jet stream.
For several years following the eruption, it was reported that the moon appeared to be blue and sometimes green. This was because some of the ash clouds were filled with particles about 1 µm wide—the right size to strongly scatter red light, while allowing other colors to pass. White moonbeams shining through the clouds emerged blue, and sometimes green. People also saw lavender suns and, for the first time, recorded noctilucent clouds."
By your reasoning that the amount of CO2 in the atmosphere is too small to have a significant effect, it follows that Krakatoa could have had not effect on the climate as well, and the reports above are pure nonsense.
The Sun shines steadilly, producing from 1360 W/m^2 to 1361.6 W/m^2 at the Earth's mean orbital distance over the entire historical sunspot record. That variation of 0.06% of insolation, or 600 parts per million, is considered to be the major driver changes in the Earth's climate by some people. By your reasoning with regard to CO2, however, it can have no effect. That is particularly the case given that the current increase in CO2 concentration relative to the preindustrial changes the Earth's energy balance (all else being equal) by 1.9 W/m^2 or (once albedo is accounted for) by 69.6% more than the difference between the Maunder Minimum and the grand solar maximum of the 1950s.
In essence, if your argument was valid against CO2, there are no changes in the Sun's radiation or atmospheric factors that could make any difference to the Earth's climate.
Of course, your argument against CO2 amounts to an argument from incredulity. It is not an example of reasoning, but of irrationality masquerading as reason. The Dilbert quote in the above link is apposite.
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scaddenp at 07:15 AM on 25 May 2016CO2 is not the only driver of climate
You claim that small concentrations of CO2 affecting temperature is illogical, but try here to check your grasp of what is logical.
Now try this for logical.
Statement A: "pauses in that warming that does not appear to be compatible with CO2 being the the principal cause of the warming."
Statement B: "temperatures are obviously subject to the effects of other factors."
See the problem? What is more, both myself and Glenn have demostrated to you that when you take into the "other effects", the temperatures are accounted for. Did you somehow fail to read our posts, or do you just have trouble comprehending things that conflict what you want to believe? I would note, that our demostrations were not simply "hand-wavy" points but quantitive based on physics and measurement.
"The various alternating periods of pause and warming have occurred on what appears to be a consistant schedule."
Not that I can see at all. How about you put up some evidence to back what you believe instead of just making wild assertions and ignoring responses? Did you base your conclusions on facts you have studied or what you would prefer to believe?
Current climate theory (asserting that earth's climate is changed by the net forcings, natural and manmade) is able to account for present and past climate change, qualitatively and quantitively, using only known physics. By contrast you seem to believe that instead climate is changed by some unmeasurable, undetectable natural cause which is nonetheless accumulating heat in our oceans at rate of 4 hiroshima bombs/sec. Now that to me defines illogical.
Ignoring responses that people make to you and simply repeating wild assertions without evidence is sloganeering and not permitted on this site.
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billev at 04:37 AM on 25 May 2016CO2 is not the only driver of climate
To state that CO2 at one cubic foot per every 2500 cubic feet of atmosphere is the leading driver of climate seems illogical to me. Since 1880 there is a strong indication of a definite pattern of warming and pauses in that warming that does not appear to be compatible with CO2 being the the principal cause of the warming. The various alternating periods of pause and warming have occurred on what appears to be a consistant schedule. This makes it difficult to believe a constantly increasing entity such as CO2 or random climate effecting incidents are influencing this pattern of temperature change.
Moderator Response:[RH] Note that, your lack of understanding the science does not mean that the science is illogical.
Please note that posting comments here at SkS is a privilege, not a right. This privilege can be rescinded if the posting individual treats adherence to the Comments Policy as optional, rather than the mandatory condition of participating in this online forum.
Please take the time to review the policy and ensure future comments are in full compliance with it. Thanks for your understanding and compliance in this matter.
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Glenn Tamblyn at 16:38 PM on 24 May 2016CO2 is not the only driver of climate
billev
You seem to be assuming that the clearest correlation between rising CO2 and some climate signal will be against the surface air temperature record. Thermodynamically, this isn't reasonable, your apparent underlying premise is wrong.
The logic is as follows:- CO2 is the largest single driver of climate in our current state, but it is not the only one.
- The Net of all drivers will determine the total radiative imbalance for the planet.
- A positive imbalance will produce an accumulation of heat in the various components of the system.
- Because of it's much higher thermal mass the oceans will represent the largest single location where heat accumulates. If the net of all forcings is positive, this is where we would expect to see the clearest, least noisy signal and the best correlation.
- Much smaller thermal masses such as the atmosphere represent a much noisier signal and are not expected to show as clear a response.
Near monotonic increase in the heat content of the oceans is the strongest, clearest expected signal based on the thermodynamics. Unfortunately air temperatures are the dataset of most interest to us since that is where we live. But they aren't the primary evidence of the underlying process, ocean heat is.
If you look at the graph in comment 2 above, although it doesn't show the most recent years, it gives a good indication of what was happening in the first half of the 20th century.
- GH Gases hadn't yet marched away as a clear forcing.
- After the eruption of Santa Maria in 1904, volcanic activity was low until the eruption of Mt Agung in 1964.
- Although it isn't clear from the graph, solar activity was likely a little higher.
- Land use impacts were still small.
In the late 20th century:
- There was higher volcanic activity.
- GH gases, particulary but not only CO2 had a much larger impact.
- Solar output has been declining slightly.
- Land use changes took off.
And very importantly, prior to 1957 we dont have any meaningful data on ocean heat content. So we can't usefully investigate the extent that atmospheric warming may have been driven by heat transfers out of the oceans. So we need to be careful to not draw more conclusions than can be justified from the more limited evidence from the early 20th century. There is some evidence tentatively suggesting that the early 20th century warming was particularly in the Arctic, possibly suggesting a change in ocean currents in the North Atlantic.
The data for climate change is a jigsaw puzzle, with clearer pictures in more recent decades and less certainty earlier on. But when the first analyses of past ocean heat content changes appeared around the turn of the century they were rightly labelled 'the smoking gun'.
Atmospheric temperatures are incredibly important to us since they reflect what is happening where we live. But thermodynamically the changes in the ocean are the biggest piece of evidence. -
scaddenp at 11:55 AM on 24 May 2016CO2 is not the only driver of climate
Billev, what is done is to measure all the of known forcings acting on the climate and recalculate onto a common basis (as if change in radiative input at the top of atmosphere). See the graph in comment 2 or 23. (In fact read the responses to Kimura). What theory would predict, is that climate would follow the net forcing. ie sum up all the positive and negative forcings. This is discussed in some detail on this post.
These are the measurements behind the attribution. You have already agreed that energy is not magically created and that climate change must have some cause.
The relevant figure is:
This is for surface temperature record. It is more striking for Ocean Heat Content which so far you have avoided, despite it being a considerably less noisy record than surface temperature. (The noise is surface temperature is ocean/atmosphere heat exchange.)
Note also that you can run models with only natural forcings, only anthoprogenic forcings, or both. The results are these (IPCC TAR).
Note that anthropogenic works better than just natural, but both is closest.
Now it is good to be skeptical and demanding a high level of certainity in drawing conclusions, but I notice that you seem to be only applying that to the question of whether CO2 causes this. You stated here
that you " I would tend to think it is an alteration in the Earth's relationship with the Sun". Where was the evidence that gave you that suggestion and did you look for the proof? The orbital forcings are extremely slow, but have been negative (would cause cooling) for millenia.The anthropogenic hypothesis passes the test of conforming to all we know about the physics of climate. The predictions made by the science (if not the strawman versions erected by pseudo-skeptics) fit extremely well with actual observations. I do not believe you can make that claim for any other potential cause of climate change.
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