This month’s open thread. Some interesting trends in ocean heat content, surface temperatures, multiple oddly reported papers (which are often linked to ambiguous press releases…) etc. But at least we aren’t working in political science…
Climate science from climate scientists...
Might as well get the usual suspects riled up right away ‘-) with a new post by robertscribbler on the steepening slope of methane concentration levels in the Arctic: https://robertscribbler.wordpress.com/2015/06/01/arctic-methane-alert-ramp-up-at-numerous-reporting-stations-shows-signature-of-an-amplifying-feedback/
The inimitable Viscount Monckton has a new apprentice who credits coal with ” the abolition of slavery… and the flowering of the Church of England .”
wili @1.
I’m not entirely convinced by the graphics of increasing levels of Arctic methane. Robertscribbler does also show the MLO data which shows the increasing rise in methane is occuring outside the Arctic. But he fails to show the pre-2000 data in his graphs which plots a steeper rise before 2000 and the start of what we could call the “methane hiatus”.
This on methane got no responses last month. Microbes eating eroded carbon
Anyone brand new to the subject should read the source page (has Scribbler started providing this on his site?)
http://www.esrl.noaa.gov/gmd/dv/iadv/graph.php?code=BRW&program=ccgg&type=ts
http://www.esrl.noaa.gov/gmd/webdata/iadv/ccgg/graphs/ccgg.BRW.ch4.1.none.discrete.all.png
Note the description; the meth’mergency people panic every month because there are orange dots up above the trend line; those mostly go away the following month, once the data are checked. See the caption, which includes:
Thanks for those insights, MARodger. I asked rs precisely those questions (as you can see in the comments section), and his response was: “The slopes are steepest in the Arctic for the most part. Barrow and Alert have the highest rates of increase (25 and 20 ppb over the last year respectively).”
And yes, methane levels rose very fast in the run up to industrialism. The question is what is it that is prompting this new acceleration in levels. One thing to keep in mind is that the atmospheric lifetime of methane is relatively short. So to even maintain the current high levels means that methane continues to be produced somewhere in much higher than historical levels. Accelerations in the increase in methane levels require even more and even larger sources.
World’s most pressing problem needs a “Global Apollo Program/me”:
http://www.theguardian.com/environment/2015/jun/02/apollo-programme-for-clean-energy-needed-to-tackle-climate-change
But there’s a misapprehension of hard science–to include both the “science” and the “hard”:
http://thebridge.agu.org/2015/05/27/should-nasa-be-studying-the-earth/
So on that:
http://en.wikipedia.org/wiki/Hard_and_soft_science
http://simple.wikipedia.org/wiki/Hard_science
Checking my _-watch–to see what time it is, just for the heck of it:
Bloomberg predicts parity for solar in India by 2020, while solar consultancy Bridge to India suggests 2018. “I think the grid parity debate is history now,” says Gopalan.
http://www.theguardian.com/environment/2014/sep/30/-sp-narendra-modi-india-solar-renewables-energy
Re #163 (from May thread)
I am not doubting these companies exist only as yet they are not as large or as influential as their fossil fuel counterparts. However given the right politics and incentives they can be but its just a shame that the fossil fuel companies don’t see their future. They still see themselves are providing all the fossil fuels they can lay their hands on to the masses. I wonder why they still think that, are they myopic or just arrogant or does the IEA/EIA projections for the future say that even with rapid renewables growth these technologies cannot provide in liquid, gas and solid form the current 18 TW and future 9 TW of power required to meet the worlds energy requirements by 2030.
I am not even sure that renewables and nuclear can provide the energy requirements, sure we can replace coal (the dirtiest fuel) I am sure of that with wind, solar and nuclear but gas and oil is not so easy.
@4 Killian, thanks for that:
As microbes processed permafrost DOC, its distinctive chemical signatures were degraded and converged toward those of DOC in the Kolyma River. The extreme biolability of permafrost DOC and the rapid loss of its distinct molecular signature may explain the apparent contradiction between observed permafrost DOC release to headwaters and the lack of a permafrost signal in DOC exported via major arctic rivers to the ocean.
http://onlinelibrary.wiley.com/doi/10.1002/2015GL063498/full
DOI: 10.1002/2015GL063498
“Our research shows that this ancient carbon is rapidly utilised by microbes and transferred to the atmosphere, leading to further warming in the region, and therefore more thawing. So we get into a runaway effect.” –Robert Spencer, FSU
Team includes researchers from UK, Switzerland, Germany, Russia, Woods Hole, and:
http://www.skio.uga.edu/
http://www.eurekalert.org/pub_releases/2015-04/uog-wcm042315.php
Site: Duvanny Yar–compliments of Permafrost Laboratory, Geophysical Institute, U. Alaska:
http://permafrost.gi.alaska.edu/site/duv
wili @6.
When folk consider potential reasons behind the stalling of the rise in atmospheric methane levels a decade ago (or the reason for the renewed rise), most I’ve read fail to attribute any culprit (eg here). However I do seem to remember reading somewhere in the last few months a paper suggesting the stalling was down to reduced atmpospheric lifetime (from 9.5 to 9.0 years?) but I can’t remember where that was.
“I am not even sure that renewables and nuclear can provide the energy requirements, sure we can replace coal (the dirtiest fuel) I am sure of that with wind, solar and nuclear but gas and oil is not so easy.”
– See more at: https://www.realclimate.org/index.php/archives/2015/06/unforced-variations-june-2015/comment-page-1/#comment-630977
Well, Pete, the physics is right: that is, there is more than enough energy potentially available with EITHER renewables or nuclear, let alone both together. So, in principle, yes–we *can.* (This does, however, assume that we find a way to cease energy use growth at some point, as we’ve discussed here on numerous occasions.)
Of course, engineering and economics are another, trickier matter. I think it’s pretty clear that we can thoroughly decarbonize the electrical grid–and, indeed that we can take considerable chunks of generation off-grid altogether. The key question is, can that–no, “will that”; unrealized possibility is of no help–happen fast enough to avoid the worst climate change?
But it’s true that non-electric energy consumption appears to be a harder nut at present. Some applications can be electrified, as the current commercial growth of EVs promises; others will require carbon-neutral liquid fuels of one sort or another, or so it appears at the moment. How fast can those changes come? How fast *will* they come? And how much of that ‘nut’ needs to be cracked how soon?
An interesting development, relevant to some recent comments:
http://cleantechnica.com/2015/06/02/big-oil-gas-embraces-carbon-pricing/
I think some cynicism is warranted, but this should end up a positive, on balance.
Pete Best:
They are neither. The issue for FF companies is the $trillions invested in assets that will be stranded when the world decarbonizes. See the International Energy Agency’s World Energy Investment Outlook.
One of the major problems that the climate projection models need to resolve and make use of, is a rather ‘weird’ case of the North Atlantic’s SST multidecadal oscillation drifting further and further apart from the Arctic’s atmospheric multidecadal oscillation.
http://www.vukcevic.talktalk.net/SST-AAP.htm
The rate of drift has been constant at least since the 1890s.
One rational explanation could be a slowdown in one of the Arctic overflow currents, possibly a major contributors to the AMOC.
#4 Pete Best
Look at current levelized cost of electricity (lcoe) new build generation prices in this chart
http://api.ning.com/files/PPvr8qsXbQmWJ543dyFtSV5d1B86gBEHqzx0Jg0yEHB7rnAuG*K631Tm3x9xH-NSVmFAFlQfNT-*w1T77–YIeK-U4heQgXK/lcoe20152019WithFuelCostBars.png
The black bars under gas and coal are variable costs (mostly fuel costs). You can see that the cheapest onshore wind generation is already cheaper than the variable costs of gas generation. By the time we get to 2030, given any semblance of the current rate of solar PV (photovoltaic) system price drops (80% in 5 years), new solar PV lcoe is going to be cheaper than the fuel costs of existing coal or gas generation.
So for a nominally 100% fossil fuel generation grid you can generate power more cheaply and make more profit by installing solar and wind alongside gas and coal plants and burn gas and coal only when the sun is not shining and the wind is not blowing. Depending on where you are and how extensive your grid, the gaps are going to be in the region of 20-40% of the time.
That’s the minimum disruptive transition that will happen by 2030-2050, driven purely by economics. Factor in demand response (“make aluminium when the wind blows”) and the 20-40% time gaps probably become 15-30% gaps in the total generation requirement.
Add a sensible modicum of carbon elimination policy, and factor in various straightforward ways of achieving up to 24 hours of storage – some Spanish concentrated solar plants achieve 83% capacity factor by storing heat in molten salt and generating from it after dark. You are down to round about a 5% gap for storage of more than 24 hours. Maybe pumped hydro can fill it, or some other form of storage, or maybe not, and it has to be gas with carbon capture and sequestration. But, hey, you’ve eliminated 95% of the carbon emissions already.
So viewed from a 2030 perspective, grids have to change to allow wind and solar to attach to bring prices down.
If you don’t intuitively believe it, look at what has happened in Texas – the US oil state. Currently wind generation is up to 10.6% with plans to increase that to 16-17%. Texas wind is at its strongest in Spring, leaving plenty of scope to add solar which clearly peaks in summer.
Ohio already gets 30% of its electricity from wind – and it’s difficult to imagine that getting too much higher as the wind only blows 40% of the time on average. Again plenty of scope to add cheap solar.
Any chance of a model/obs comparison this year, Gavin?
RE #5
I’m fully aware the that AMEG-type folks are very much at one end of the continuum of opinion on methane, but do they really have a big panic every month, and try and convince people that one months figures are definitive proof of imminent methane armageddon?
It seems a trifle self-defeating if they do, we aren’t goldfish!
Wili, #1, I think some of the climate scientists that run this site are getting sick of you posting links to hype blogs. I think one of them even admonished you as being stupid and irresponsible a couple of months ago. You saw that right? It didn’t seem to dissuade you. Maybe you ought to take a cue from them, and quit linking to doomer porn.
Re #12 and #13 and #15
I have no argument with any of the points raised here regarding the available renewable technology ( I think the number of global nuclear reactors needed would be a worry) , its so called grid parity with fossil fuels, the storage needed in times when the sun is not shining and the wind is not blowing (compressed air, molten salts etc or in batteries.
The big concern is the political and economic will but as you are suggesting and as the system currently works, subsidies can be transferred, R&D can be done, and agreements can be reached internationally to stop us from hitting 3C or higher. 1.5 to 2C is harder but not yet impossible but its a big ask apparently.
Newspapers such as the UK Guardian make it all seem possible with article after article describing how solar and CSP along with wind and energy storage can given the correct research and incentives to deploy mitigate carbon emissions sufficiently to avoid the worst of the climate impacts but as the world still gets 85% of its energy from fossil fuels and these industries have been good at avoiding renewable energy deployment for 40 years means that to me at least its still not going to be easy even though theoretically it is plausible.
One big concern is transport, all of it uses oil or gas ( a few hybrids and electric vehicles are available but they are expensive), shipping, trains (electric ones use coal and gas), road freight and passenger vehicles as well as flying are all tied into fossil fuels. Only one sector, passenger vehicles and a few buses have made inroads into using alternative energy sources. the rest of it will take a long time and major research to get them to be able to use energy from other sources. The sheer size and weight of transport means that other energy sources probably cant be used except for some kind of biofuel which as yet cant scale to the needs required.
Just a few thoughts.
One thing at a time, Pete. We are talking about many decades.
Re 5: Hank, sparse air monitoring at ground level tends to understate methane. Our “natural” methane source monitoring is very sparse.
The rise in methane concentrations at ground level in the Arctic atmosphere is no more proof of an increase in methane releases than finding a few termites under the bathroom sink is proof of a termite infestation.
However, in either case, the prudent manager investigates with due diligence.
Based on the current state of air monitoring science, and the value of the property (Earth), would you say the managers are exercising due diligence in the task of Arctic Methane Monitoring?
Paleo-Perspectives on Potential Future Changes in the Oxidative Capacity of the Atmosphere Due to Climate Change and Anthropogenic Emissions
Current Pollution Reports, 5 May 2015
DOI 10.1007/s40726-015-0006-0
Shorter: interfering with atmospheric OH level viewed as possible, unwise.
For relevance, see Methane on the Rise Again, DOI: 10.1126/science.1247828, 493 (2014) Euan G. Nisbet
Shorter: many possibilities, few looking for answers
The point wrt “renewables” is that never in history have we “transitioned” away from any energy resource. We have only added in new ones to the mix to keep up with and accelerate growth. Many countries still have wood as a large portion of energy inputs. We never transitioned away from coal in fact it increased significantly.
To talk about “renewables” replacing FF use is naive. To build out “renewables” at a rate that allows for Global economic growth (so billions don’t starve and die) plus enough to replace existing FF use is a monumental task and would take every last ounce of FFs as well as every other natural resource available. All of which are facing serious constraints already.
Just think about it a bit before you wave your hand and say in the future FFs will be a thing of the past and we will all be going about our merry way powered by “renewables” in such an off hand way.
The fantastical world we live in that gives one the impression that absolutely anything is possible was only possible because of massive amounts of cheap almost free FFs which is in or responsible for 95% of everything in your life.
Tried asking this over at skepticalscience and after awhile without response I had someone direct me here to ask as well. Hope this is reasonably on topic?
I’m trying to understand model tuning correctly. It seems from most references I can find via the IPCC and papers like that by Mauritsen et al, it is pretty common practice when tuning climate models to adjust cloud parameters to balance TOA energy. It sounds like it is again pretty universal that this is a very necessary step to prevent unrealistic drift of TOA energy balance. Given that TOA energy balance drives everything in our climate, betting that right is pre-requisite to reasonable model behaviour. I’ve got follow up questions on interpretting this, but am I even correct in understanding things as expressed thus far?
Anyone have a reference for the effect that CO2 absorption by the oceans will have on the oxygen concentration in the atmosphere?
#23 jef,
Well, if we are going to talk mitigation, let’s try to get history straight.
“The fantastical world we live in that gives one the impression that absolutely anything is possible was only possible because of massive amounts of cheap almost free FFs which is in or responsible for 95% of everything in your life.”
Like what? Other than perhaps universal air travel, there is very little technology that could not have been developed in about the same time with much constrained availability of fossil fuels. You are simply conflating quantity and quality in your perception of this “fantastical world”. What that “massive amounts of cheap almost free FFs” gave us was a ridiculously inefficient system of energy consumption.
And why do you need “Global economic growth” to prevent starvation? There are lots of people surviving on a couple of bucks a day or less; maybe we fortunate sons could forgo a latte once in a while and chip in?
> stupid, irresponsible
Eric was referring to “commentators” — which I think describes the people writing the tasty tempting items that are put out there for public consumption.
Rebunking that stuff, well, who of us has never reposted the stupid, when with a little thought we’d have filtered it out? We nonscientists all have faced the steep learning curve to separate what’s food for thought, from what’s chumming for chumps.
The art is to ask questions we truly believe maybe worthwhile.
And await correction.
Got a fifth grader handy? Ask her/him to try reading this explanation of energy and climate change and tell us how understandable it is. Seems decent to me on first perusal.
Page down a bit to get into that part.
#23–Jef, with all due respect, all you are doing is waving your hands. There is no evidentiary basis whatever for the claim that “To build out “renewables” at a rate that allows for Global economic growth (so billions don’t starve and die) plus enough to replace existing FF use is a monumental task and would take every last ounce of FFs as well as every other natural resource available.”
To demonstrate that, let me ask a couple of questions: What approximate rate of economic growth is required to avoid a famine killing ‘billions?’ And what approximate rate of growth in renewables would be necessary to provide sufficient energy?
Let me guess: you don’t know, either.
But let’s look at some numbers. In 2012, the world used something like 155,505 TW-h, according to the IEA. That’s total consumption, not just electricity.
(http://en.wikipedia.org/wiki/World_energy_consumption)
Divide out the hours in a year, and that’s roughly 17,750 GW.
In 2013, the world added 80 GW of new renewable power, on roughly $250 billion USD in investment.
(http://www.ren21.net/Portals/0/documents/Resources/GSR/2014/GSR2014_KeyFindings_low%20res.pdf)
At that rate, it would take us a little over 2 centuries to replace all existing capacity with renewables–by which time, we’d be long overdue to begin replacing the replacements. Viewed that way, we would seem to have indeed a ‘monumental task.’
However, total investment in energy in 2013 was roughly 1.6 trillion, of which “more than $1 trillion per year, is related to the extraction and transport of fossil fuels, oil refining and the construction of fossil fuel-fired power plants.” So, neglecting for the moment the problems of transitioning, for 1.6 trillion per year we could presumably multiply our added capacity by a factor of 6.4. That in turn would imply that we could replace our energy infrastructure in roughly 30 years.
Of course it’s not that simple; we obviously need to keep fueling existing vehicles for a while, and ditto existing power plants till they can be replaced. So, to a first approximation, we’d need to spend the ‘more than $1 trillion’ per year to keep the status quo going, while spending a further trillion and a half to do the replacement.
It would get cheaper: every year, we’d have more renewable energy, and (since fossil fuel infrastructure has a limited lifetime, just like everything else) less fossil fuel. That would mean that we’d need less fuel. Moreover, for both wind and solar, costs have fallen dramatically. If we ramped up production by a factor of 6, the end result would be economies of scale and an acceleration of the already rather remarkable price declines.
Unrealistic, still? Of course. This is very much ‘back of the envelope’ stuff. But if you look at the same report that I quoted, there are some indications that I’m not totally off in the weeds. Their ‘new policies’ scenario envisions:
So, we’re on the hook for more than $20 trillion no matter what, if we want to preserve existing capacity levels.
To put us on track to meet the goal of limiting warming to 2 C, this report adds another $13 trillion to the total, for a cumulative total of $53 trillion in energy investments.
Is that hard? Of course it is. That’s why some of us have been stressing the importance of pressing forward. Had those giving early warnings been heeded, we wouldn’t be in such a deep hole, but there you are. Nonetheless, it is certainly doable, with GWP at around $75 trillion.
Oh, and by the way, it’s also not true that “…never in history have we “transitioned” away from any energy resource.” Unless you know a place where I can buy some whale oil for my lamp?
Just think about it a bit before you wave your hand and say in the future FFs will be a thing of the past and we will all be going about our merry way powered by “renewables” in such an off hand way.
The fantastical world we live in that gives one the impression that absolutely anything is possible was only possible because of massive amounts of cheap almost free FFs which is in or responsible for 95% of everything in your life.
Comment by Jef — 3 Jun 2015 @ 11:31 AM
Now that concept of “transition” is one I’ve been really trying to wrap my brain around for quite some time. The scope and depth of our situation is massive and time is short. “Given enough time” should be the qualifying statement included in future projections of what is possible. Personally, I think anything is possible… “given enough time.”
The problem is nobody seems to know exactly how much time we have and we keep hoping we don’t run out. What happens when we find ourselves another 5 or 10 years down the road and we’re still burning FF’s?
Kevin, models can be run many different ways including investigating factors that get TOA wrong. For perspective look here:
http://www.easterbrook.ca/steve/2010/11/validating-climate-models/
and linked posts.
btw Steve is writing a book, due out in September.
> Mauritsen
Much discussed previously; this will find some of that:
https://www.google.com/search?q=site%3Arealclimate.org+tuning+mauritsen
Re #19 Pete Best
The impending changes caused by unsubsidised wind and utility scale solar PV generation already being cheaper than fossil fuel in a lot of places are coming – you can see them in LCOE prices currently. They will be driven primarily by the market economics. We are at a tipping point where there is going to be significant disruption in some electricity grids purely because of this. Government policy changes are needed to prepare for this to happen smoothly (because it will happen smoothly or not). Once the change starts, the volume of renewable generation units (panels / turbines) produced will increase and prices will drop further much faster. The estimate is that each doubling of solar PV panel volumes will reduce prices by 16%. This results in 16x the volume halving the price. At this stage the game is up for any other kind of generation getting a look in while the sun is shining.
The extent of this automatic disruption will be for renewables to provide 50-70% of units generated which is basically the times when onshore wind is blowing or the sun is shining (though the renewables capacity proportion will have to be higher than 50-70%). To get above this figure does need significant government policy changes, and probably continuing subsidies for offshore wind (capacity factors > 50% and no NIMBY effect), and for energy storage technologies and solutions.
Ground transport is likely to migrate big time to battery electrical power when batteries are available at $150 / kWh. Tesla’s home storage unit currently comes in at $350 / kWh. They are expecting a 30% reduction once the Tesla “gigafactory” is at full production in 2020, which brings it down to $250 / kWh on still a fairly small scale of output (500,000 units per year). Expansion to ten times the gigafactor volumes would doubtless do it. In the meantime there are other promising battery technologies which might tip the balance earlier. But there’s no doubt it is coming – again just from the sheer expectation of price reductions due to mass market economics.
And incidentally, the cheapest training aircraft to learn to fly on is now an electric trainer powered by lithium-ion batteries, because of the fuel cost saving. It only stays in the air for 30 minutes though. More to come in the future.
Re #23 Jef
EROI for wind is around 20 and for solar PV upwards of 10, so only the first couple of years of generation would be taken to manufacture double the capacity on a “virtuous chain reaction” basis. Whereas tar sands and similar technologies have an EROI in single digits. As wind and solar PV have developed to a mass market the cost has come down tremendously, and this would not have been possible if the EROI had not also gone up quite a bit. So the figures you probably base your assertions on are almost certainly well out of date now. Thin film solar estimated range of EROI is 10-70.
Jef:
I’m skeptical of your claim, but in any case it’s highly likely that billions will die prematurely if we don’t replace existing FF use before using every last ounce of them.
You’re saying mass dieoff of the Earth’s human population is unavoidable, then. I’m still holding out hope that you’re wrong, but I’m glad I won’t be leaving any offspring.
> would you say the managers are exercising due diligence
> in the task of Arctic Methane Monitoring?
You should ask a scientist. Several here have also weighed in, you can look it up.
You know who those managers you rely on are, don’t you?
Gazprom.
They are extracting and selling the gas as fast as they can.
Can you get them some kind of funding for saving the climate from the methane monster?
Do that and they can drill, sell, and burn even faster.
Or you can work on stopping burning fossil carbon, the real problem.
Put your money and best effort into what you think most useful.
Bless your heart.
http://arstechnica.com/science/2015/06/did-western-antarcticas-ice-fall-into-the-sea-120000-years-ago/
Kevin McKinney #29:
Thanks for your very interesting post.
A question however: where did the number “6.4” come from in this paragraph:
“However, total investment in energy in 2013 was roughly 1.6 trillion, of which “more than $1 trillion per year, is related to the extraction and transport of fossil fuels, oil refining and the construction of fossil fuel-fired power plants.” So, neglecting for the moment the problems of transitioning, for 1.6 trillion per year we could presumably multiply our added capacity by a factor of 6.4. That in turn would imply that we could replace our energy infrastructure in roughly 30 years.”
I could not figure it out. Pardon in advance if it is something really obvious that I missed.
alan2102: I think the 6.4 is the result of dividing the amount of global energy investment (2013) by the amount of renewables investment (2013).
Jef, when petroleum came along in 1859-1860, the whale oil industry collapsed almost overnight. So replacement very much HAS happened in the past.
#37,alan–The “6.4”? Almost spelled that out, and evidently should have; it’s 1.6/.25, the ratio of the total yearly energy investment to the renewable fraction of that investment.
#19 There are various approaches to creating carbon-neutral liquid fuels. Here are some:
http://eee.columbia.edu/carbon-neutral-methane-energy-production-hydrate-deposits-0
http://en.wikipedia.org/wiki/Methanol_economy
http://en.wikipedia.org/wiki/Carbon-neutral_fuel
#23 “The point wrt “renewables” is that never in history have we “transitioned” away from any energy resource.”
We don’t have to transition away from any energy resource. We just have to prevent the pollution.
@Pete Dunkelberg in 31,
I can’t find where Steve discusses model tuning at all. He talks a lot about about how Software Quality Assurance is wasted on climate models, but I can’t find any comments or enlightenment on tuning methods.
@Hank Roberts in 32,
Thanks for the link, but again after going through each of the google results non of the references to Mauritsen here on realclimate that it pointed me to said nothing further or clearer on tuning. Most of the discussion on realclimate is of a different one of his papers on tuning in an Iris effect, but not on standard/typical tuning methods. The results do however have a comment posted by the man himself here, so that makes me hopeful even if I am still non the wiser.
For the record, I’ve read the entire IPCC AR5 chapter on model assessments, I’ve read Mauritsen’s entire paper on tuning, and several of the other journal articles on tuning that the IPCC report references. From that my unexpert reading seems to come up with the following 3 points, but I would really like a more expert verification that I’m correct or not:
1. It is pretty universal that tuning TOA energy is a very necessary step to prevent unrealistic drift of TOA energy imbalances.
2.It is pretty common practice when tuning climate models to adjust cloud parameters to balance TOA energy.
3. TOA energy balance drives everything in our climate, getting that right is pre-requisite to reasonable model behaviour.
If it’s an interesting enough question (and if we “show our work so far”) one of the scientists may come along and help find better answers.
> tuning
You read this part from AG4? (para.breaks added for readability onscreen)
http://pubman.mpdl.mpg.de/pubman/item/escidoc:1765216/component/escidoc:1765214/ar4-wg1-chapter8.pdf
Is your question about the word “justifiable”? If so, we can hope a statistician may offer help …
@Hank, Thanks, I had read most of the AR4 portion as well back before AR5 was out. I am aware that tuning practices take into account realistic, observed values for parameters being tuned. AR5 references another paper though by Golaz, Horowitz, and Levy that tests 3 different cloud parameter values against the same model. They keep each of the 3 within observationally reasonable ranges, and also still yield the desired radiation balance. The parameter with the closest values to observation though actual did the poorest job of modelling recent warming.
So I understand that the parameters being tuned are being done in a manner to remain as close to observables as we have in existence. My biggest concern is if I’m understanding correctly or not that TOA energy balance is being generally hand tuned for as standard practice. I know we’ve left behind the days of just adding energy fluxes to balance things, but hand tuning parameters until TOA energy balance matches observations is still tuning for better TOA Energy balance. Am I understanding things accurately with all of the above, or am I off the rails in some dark corner of ignorance?
Thank you, Mr. Roberts to the paper on WAIS collapse in the Eemian. I see that Prof. Steig is lead author, so perhaps he would answer a question of mine: Would one expect a weakening of the ACC due to change in wind patterns as WAIS dropped ?
Kevin-san,
I’m writing a tutorial on how to write radiative-convective models of planetary atmospheres. That’s a much simpler business than writing a GCM, but it’s a start. Maybe it will help a bit.
General note on several posts above:
We need to start thinking along an entirely new metric: ERORI, or Energy Returned on Resources Invested.
Ultimately, EROI will be meaningless. EROEI does not include the mesure of the amount of resource available. EROEI + ERORI should do the trick.
Found that paper, I think, if anyone’s interested:
Cloud tuning in a coupled climate model: Impact on 20th century warming
First published: 27 March 2013
DOI: 10.1002/grl.50232
Cited by: 7 articles
Abstract
[1] Climate models incorporate a number of adjustable parameters in their cloud formulations. They arise from uncertainties in cloud processes. These parameters are tuned to achieve a desired radiation balance and to best reproduce the observed climate. A given radiation balance can be achieved by multiple combinations of parameters. We investigate the impact of cloud tuning in the CMIP5 GFDL CM3 coupled climate model by constructing two alternate configurations. They achieve the desired radiation balance using different, but plausible, combinations of parameters. The present-day climate is nearly indistinguishable among all configurations. However, the magnitude of the aerosol indirect effects differs by as much as 1.2 Wm−2, resulting in significantly different temperature evolution over the 20th century.
I believe I can reasonably claim to be an intelligent and well read layman. I read this blog from time to time hoping to learn more about climate change and what to expect for the future, and occasionally, I read the comments to learn more.
My first impressions — for what they may be worth to this audience — the comments seem unusually snarky and impatient with the questions and comments posed by non experts visiting the site. I realize this is a relatively sedate site, compared to numerous other sites and the topic is controversial to say the least — even so — my first impression of this site is confirmed by further perusals.
I think this community does itself, climate science, even science per se, a great disservice through the attitude it projects — at least to this ignorant … go read the scientific literature … we already told you get out of here .. layman. I made one comment in the dim past so my opinion is based purely on my assessments while lurking.
I will continue to come here for the main posts as they appear … but I think I will refrain from looking further at the associated comment threads.