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Comments 19251 to 19300:
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HK at 21:32 PM on 30 June 20172017 SkS Weekly Climate Change & Global Warming Digest #25
Another option is to include all the data until now and then do an "analysis" by drawing a straight line between April 1998 (anomaly 0.8928 K) and May 2017 (0.6267 K) and conclude with a cooling trend of -0.139 K/decade.
It’s amazing how wishful thinking can override reality whether the topic is global warming or for instance some of the moon landing deniers’ claim that rocket engines don’t work in space!
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Daniel Bailey at 20:51 PM on 30 June 2017SkS Analogy 9 - The greenhouse effect is a stack of blankets
Those wishing to dismiss current high levels of atmospheric CO2 by comparing them to earlier periods of high levels of atmospheric CO2 need to keep up with current research:
"The evolution of Earth’s climate on geological timescales is largely driven by variations in the magnitude of total solar irradiance (TSI) and changes in the greenhouse gas content of the atmosphere.
Here we show that the slow ∼50 Wm−2 increase in TSI over the last ∼420 million years (an increase of ∼9 Wm−2 of radiative forcing) was almost completely negated by a long-term decline in atmospheric CO2. This was likely due to the silicate weathering-negative feedback and the expansion of land plants that together ensured Earth’s long-term habitability.
Humanity’s fossil-fuel use, if unabated, risks taking us, by the middle of the twenty-first century, to values of CO2 not seen since the early Eocene (50 million years ago).
If CO2 continues to rise further into the twenty-third century, then the associated large increase in radiative forcing, and how the Earth system would respond, would likely be without geological precedent in the last half a billion years."
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JamesMartin at 11:39 AM on 30 June 2017Temp record is unreliable
Eclectic — As I explained in a previous post, which SkepticalScience took down, I checked on Heller's sources and scaling of his graphs, and it turns out that his presentations stand up to scrutiny whereas the those from SkepticalScience don't even make sense. That's why I have defended Heller in his work. There is nothing personal about it.
Moderator Response:[PS] Removed while account investigated.
[DB] Iterative sock puppet (number 11) of serial spammer cosmoswarrior has been removed from further participation in this venue. As will all of your future such. It might profit you better to seek a more amenable village to infest.
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JamesMartin at 11:23 AM on 30 June 2017Temp record is unreliable
The hangup that SkepticalScience.com has in regard to temperature data is that you are exclusively using datasets at least as current as 2015, all of which are tainted by the 2015 adjustments. No wonder you make statements such as
"It is very clear that use of the new data sets make almost no difference to the trend."
If you want to do a fair assessment of the impact that the 2015 corrections had on the historical temperature data, you must dig up those archived datasets recorded before 2015. Otherwise, you just go around in circles claiming that the warming hiatus is over or never was while the corrections "make almost no difference to the trend". Well, if the corrections make no significant difference in the trend, and the current trend is hiatus, then wouldn't we still be in hiatus?
Moderator Response:[PS] Removed pending moderation investigation.
[DB] Posting rights rescinded due to flagrant sock puppetry.
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JamesMartin at 11:20 AM on 30 June 2017Temp record is unreliable
Tom Curtis — Your ineptness with these graphs never ceases to amaze me. Take another look at the figure below before you delete it again.
Notice that the tick marks of the two horizontal axises align perfectly with each other as I showed with the short green lines connecting them. Similarly, the tick marks of the pair of vertical axises also align perfectly. Therefore, the scaling of both the horizontal and vertical dimensions of the two plots are identical. The reason the decimal points may not align as well has to do with the different font sizes of the plot labels, and NOT the data or scaling. Therefore, Tony Heller's plots and animated .gif file still stand as a fair presentation of how the 2015 "corrections" rewrote temperature data since 1880.
What happened in the case of this figure is a prime example of your long history of deleting my comments, giving your faulty understanding of what I said, and then trying to discredit me on the basis of your spin on the story instead of what I actually said. Can we say "strawman tactics"?
At this point, it is quite clear to me that you are either totally incompetent or intentionally deceptive in your position, and in either case, for me to have any sort of intelligent discussion with you is simply not possible.
BTW, I saved screen snapshots of my postings before you and any "moderators" had a chance to remove them. Therefore, if "push comes to shove", it won't be just your word against mine as to what was said.
Moderator Response:[PS] TC is not a moderator. Posts removed because sockpuppet of someone who cannot comprehend comment policy and let alone the science.
If you wanted to discuss science (which you are apparently incapable) then you needed have heeded the comments policy. No exceptions and no further chances.
[DB] Posting rights rescinded due to boringly iterative sock puppetry.
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villabolo at 10:55 AM on 30 June 2017SkS Analogy 9 - The greenhouse effect is a stack of blankets
"Some skeptics refer to a time about 600 million years ago, during the late Ordovician..."
My understanding is that the Ordovician era was from approximately 488 million to 444 million years ago. :-)
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nigelj at 09:15 AM on 30 June 2017SkS Analogy 9 - The greenhouse effect is a stack of blankets
Yeah I think paragraphs one and two are excellent. The basic blanket analogy is just so good, simple and clear. I have just recently purchased some thick curtains, and I'm surprised just what a difference those make to temperatures, especially noticeable when I wake up in the mornings.
Paragraph three sends a slightly mixed message. The total number of blankets is crucial of course, but the rate is very important in relation to carbon cycles.
The rate is also important because adpatation becomes harder if rates of change are rapid. It's also just too easy for people to say total quantities will be far in the future, and not our problem. Both rates and total numbers are equally important arent they?
I agree about the late Ordivocean. This is sceptics cherry picking a period that suits their perspective, and its doubly frustrating because they seem unable or unwilling to grasp the totally plausible explanation you documented. In fact past climate history is very complicated and sometime superficially inconsistent with theory, but only a combination of various factors like solar changes along with greenhouse gases and other geological factors seem to explain everything, including the apparent inconsistencies and oddities. It appears to have been a complex evolving sort of system interracting in numerous ways.
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Tom Curtis at 07:47 AM on 30 June 20172017 SkS Weekly Climate Change & Global Warming Digest #25
HK @2, I am sure that that section of RSS TLT from 1997-2015 will be just as popular as ever. Of course, it will be mandatory to exclude 2016 because of "the impact of a large El Nino", a reason I have already seen offered and which, oddly, does not seem to provide a reason to exclude 1997/98.
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JWRebel at 05:39 AM on 30 June 2017SkS Analogy 9 - The greenhouse effect is a stack of blankets
The analogy was doing well up until point 3, the rate of putting on blankets and the Ordovician goes a little far; it's complicated. The rate matters especially with relation to the carbon cycle and weathering. Blankets are not added continuously, and there is no blanket cycle with blankets dissolving. Not to mention positive feedbacks under those blankets!
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HK at 23:52 PM on 29 June 20172017 SkS Weekly Climate Change & Global Warming Digest #25
....and let me have the pleasure to introduce.....RSS TLT v 4.0!
According to their own chart, the trend in the lower troposphere has been 0.184 K/decade since 1979. That’s actually a little more than most surface records!
I guess RSS team will become even less popular among the climate deniers from now on! -
nigelj at 13:48 PM on 29 June 2017Climate scientists just debunked deniers' favorite argument
BJChip says "I do agree it would be good to force the issue regarding truth, but as long as we have a media that is owned by the 0.5% , and news that has to be sold like soap powder, we are just as owned..... I could not live on the same block as a Pruitt or a Lamar Smith. "
I agree on both points.
Regarding the media, its not just the owners. I have seen a big change in our main newspapers over the last couple of years. They used to be at least moderately balanced, but now print far fewer articles critical of things like fossil fuel interests, food companies, sugar consumption etc and instead have now tended to become almost total corporate apologists. It's possibly fear of losing advertising to social media or other internet media.
It's reached crisis point, unfortunately right at the wrong time for getting facts out on climate change. I dont know what the answer is, but the mainstream media are turning to trash. It's not fake news in the flawed and ridiculous way Trump claims, its near total corporate capture.
I'm a very easy going guy who will normally talk to people of all ideologies and classes, but these days I would struggle to socialise with some of these climate denier people. And frankly I dont have to. It's not their beliefs as such, it's the underhanded distortion of so many issues, which I think is largely cynically deliberate.
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nigelj at 13:01 PM on 29 June 2017Explainer: Dealing with the ‘loss and damage’ caused by climate change
Art Vandelay @26.
Land area or total population doesn't come into the question of compensation or assistance. Basically high emitters as individual people have caused more of the problem therefore they should pay more to fix the problem. It's like a situation where several parties are polluting a river, well the party causing the most damage should pay the most to fix the problem. Everyone else will pay something but less.
This is true within countries, but it is also true when applied between countries on a per capita basis. Per capita is the only way of determining the issue. In reality it means rich people owe a duty to poor people as rich people have been the larger emitters in the main. But it doesn't obviate the need for poor people to also reduce emissions.
I agree with your general assertion that curbing population growth can only help to reduce emissions, and I doubt anyone would seriously disagree. Rates of population growth are falling in many countries anyway, due to the demographic transition. Hopefully countries do what they can to speed up that process. Paris did not stipulate measures to reduce emissions, and this was left to individual countries and there's nothing stopping them considering population growth.
However changing rates of population growth is such a slow process even under ideal conditions. I just dont see how it is of much benefit to keeping temperatures under 2 degrees. We are almost entirely reliant on changing sources of energy.
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One Planet Only Forever at 12:19 PM on 29 June 2017Climate scientists just debunked deniers' favorite argument
bjchip@8,
It is curious that in the USA and many other nations an advertiser who tries to present actual but unflattering facts about a competitor can be penalized or at least stopped from continuing to do it, and the penalty is worse if they misrepresent the facts about a competitor, yet no such penalties apply to government actions or election campaigns.
The absence of Good Reason Ethical standards for government activity, and the inconsistent application of things like the advertising penalties (used more to limit public awareness of unacceptably activity than to correct for deliberate unjustifiable wrongs being done), are indications of how incorrectly developed a nation has become.
The first step to "Getting Better Behaviour" is exposure and increased understanding that the current behaviour is unacceptable. The exposure is growing. Getting acceptance that the bahaviour is unacceptable enough to require effective significant penalties is likely not that far away (and understandably faces fierce opposition).
The most interesting aspect of this attack on climate science is the way the attackers/deniers appear to be unaware that their actions are shattering illusions/preceptions of special status and admiration for the wealthy and powerful today. It is becoming more apparant to more people that recognition and reward is not owed to someone because of the impression or image they create (their profitability and popularity may or may not be deserved). There actually is a reality that can be understood by everyone, the need to help others and help improve the future for all of humanity. And images or dogmas that are inconsistent with that understandable reality eventually get shattered (or there is no future for humanity).
Sadly, a lot of damage is usually able to be done before the shattering of unjustified impressions makes deserving losers of the ones who have been the biggest trouble-makers. There are many other exmples of how understandably unacceptable things are gotten away with in pursuit of personal benefit and profit. But climate science has unintentially produced a Huge Unmistakable Bad Example Response that everyone can understand to be Bad, even if they refuse to admit that it is bad.
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bjchip at 10:48 AM on 29 June 2017Climate scientists just debunked deniers' favorite argument
As I pointed out on hotwhopper where this was also raised - what Santer's team did was to effectively validate what Foster & Rahmstorf did earlier.
We don't have any ability to actually penalize lying and misrepresentation in the service of the people who think "greed is good". The penalty is eventually to the society as a whole, which will ultimately disintegrate. The losers are everyone not in that 0.5% winners circle and the real penalties are going to be rather harsher.
Just not on this generation.
I do agree it would be good to force the issue regarding truth, but as long as we have a media that is owned by the 0.5% , and news that has to be sold like soap powder, we are just as owned. So not happening. What needs to happen is the effective dissolution of the United States of America and the regions choosing their own paths as to whether to be independent nations and what laws to apply to each. I could not live on the same block as a Pruitt or a Lamar Smith. I am lucky that I don't have to.. but I am on the same planet so they aren't far enough away.
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One Planet Only Forever at 09:27 AM on 29 June 2017Climate scientists just debunked deniers' favorite argument
How can presentation of anything that is unjustifiably contrary to 'a fuller better understanding of what is going on and the application of that understanding to help improve the future for all of humanity' become a legally punishable offense, with the presenter and everyone who tries to unjustifiably defend or excuse the misrepresentation of understanding being penalized, with the magnitude of the penalty being based on the severity of the implications of their misrepresentation for the future of humanity, and the penalty including Elected Representatives and Supreme Court members to be removed from their positions (not waiting for the next election or for a replacement Justice to be identified)?
The real treat of potentially Losing Big League may be the only way to limit the attempts of those who grow up believing they can get away with deliberately trying to get as much advantage as possible from behaving as unacceptably as they can get away with.
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scaddenp at 09:17 AM on 29 June 2017Climate scientists just debunked deniers' favorite argument
I should also say looking at straight temperature of any layer in ocean in most certainly not immune to internal variability. However, I do agree that OHC 0-2000m globally averaged is indeed a more stable measure of climate than surface temperature. However, if you look at it:
you see that still quite a lot of variability from ocean-atmosphere exchange. That is where heat from El nino comes from.
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nigelj at 08:38 AM on 29 June 2017Climate scientists just debunked deniers' favorite argument
The models diverge from reality after about 2005, but only slightly. This is short term, so is most likely short term natural variation. As you say its not climate sensitivity and could be volcanic activity etc.
I would add natural variation like enso or pdo cycles could be difficult to 100% accurately incorporate into into models , as it's not perfectly regular, so you cannot read anything much into a divergence of temperatures over relatively short terms up to about 25 years.
In contrast sea level rise is slightly ahead of model estimates. Nothing from Christie on this. Again there's so much going on its hard to make completely 100% accurate predictions, but things can be more than predicted as well.
Do we do nothing on climate change because we don't as yet have 100% accuracy? It's like saying lets not treat this very sick patient, because we dont 100% understand how the body works, and can't 100% accurately predict outcomes of surgery or drugs. We would obviously treat the patient.
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scaddenp at 08:24 AM on 29 June 2017Climate scientists just debunked deniers' favorite argument
rocketeer - how would extract those ocean temperatures from the modelling grid in a useful way and present compare them? One way is instead to extract global OHC over various depth ranges from models and compare, but I understand that is not trivial and not routine.
Anyway, data from models available here.
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One Planet Only Forever at 07:14 AM on 29 June 2017Explainer: Dealing with the ‘loss and damage’ caused by climate change
Art Vandelay@26,
We are not even close to agreement. To minimize the chance of continued misunderstanding I will make a more complete presentation of my understanding of the required changes for humanity to develop a sustainable better future for the almost limitless future that is possible on this amazing planet (I am open to Real Good Reasons to improve that required objective of human activity - I am not moved by temptations to believe artificial attempts to create alternative beliefs that may temporarily develop popular support for unjustifiable pursuits of profit or job creation or tax collection ...).
To achieve that objective all of human activity needs to be developed to be of zero-GHG impact (2050 is the target date often discussed for achieving this) with major correction required for over-development that has occurred in the wrong directions. So beyond that time there can be no nation believing it is OK to have GHG generating activity as part of what its population benefit from. So I disagree with your presumption that nations can continue some level of impact, but just limit it based on the size of the land area of their nation. The leadership of all nations need to get all of their population to understand that the end of such activity is going to happen and the sooner the better.
Further. there must be a limit to the total impact accumulated by the time of finally achieving the development of zero-added-GHG activity. The lower the total impact is the better the future will be. And current day generations in nations need to be accountable for the impacts of their predecessors towards the total accumulated impact, no 'forgetting about the past', especially no excusing what winners/leaders have done since 1972 when a clear awareness of the concern was globally established by the Stockholm Conference. Serious consideration needs to be given to penalizing people for what they have been doing since that time, with steeper penalties for what they did since the more recent reinforcements of that understanding.
Using hydrocarbon operations process controls terms, the High High High Level Alarm (Imminent Disastrous Consequence Level) that has been internationally agreed by those who rationally consider distant motives (my deliberate paraphrasing of a quote from John Stuart Mill's “On Liberty”) is the accumulation of impacts that has a reasonable likelihood of resulting in 2.0C warming of the surface since pre-industrial values. And the High High Level Alarm (An Emergency Level to be avoided) is 1.5C warming impact. The High Level alarm would be 1.0C but the irresponsibility of our predecessors has already pushed things to that alarm point. And a Normal Operation range would be between 250 and 300 ppm of CO2.
Those objectives cannot be achieved by any of the highest per-capita impacting people being allowed to continue their preferred ways of benefiting, no matter how big the area of the nation they are living in is. If there are considerations of population limits, the highest per-capita impacting people need to be reduced first.
The proper way to avoid reaching alarming limits is to have the wealthiest and most influential people prove they deserve to be leaders/winners among global humanity by most rapidly changing their ways to zero-GHG-impact, including not being invested in potential to benefit from any business that pursues profit from activity that will create GHG impacts (That will mean many perceived to be wealthier people will dramatically lose perceptions of wealth, but such corrections would indicate how damaging and worthless their ways of Winning had been, and they should be thankful to not have punitive damages applied for their past transgressions).
What is becoming undeniable is that the freer actions of people (people freer to believe what they want and do what they please), results in unacceptable unsustainable damaging Winning. The marketplace can be a very useful mechanism for determining what deserves to be discouraged/rewarded, but only if all of the participants are dedicated to pursuing increased awareness and improved understanding to help advance humanity to a sustainable better future for all (all people need to be moved by rational consideration of distant motives - especially those with the largest influence).
So my understanding of what is required is - the nations whose previous citizens had created the most impact so far need to most aggressively change the behaviour of their richest and most influential people today, all of them, no more 'freedom to believe and do as they please if they can afford it or if they can get popular support for getting away with it and as long as it can't be proven conclusively in a court of law to be against a specifically worded and enacted law' Bad-reason Poor-Excuse Non-sense. No more allowing a portion of the population to get aay with making a bigger problem that another portion of the population is trying to mitigate. No more making or allowing excuses for the “Leaders/Winners” to behave understandably less acceptably in pursuit of profit and popularity.
That last point is the real better understanding that climate science has unwittingly and unintentionally exposed in a big way. And it is why climate science faces such a vicious and persistent resistance. Many perceived Big Winners really understand that they have A Lot To Lose, and they can even understand that they deserve to lose it.
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El_Jairo at 06:59 AM on 29 June 2017There is no consensus
I can't edit, so I will rephrase that last sentence.
Don't just accept what is presented to you, think critical and challenge the assumptions.
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El_Jairo at 06:55 AM on 29 June 2017There is no consensus
I am not going to make the argument again but post 712 sums it up splendidly.
TLDR: read the paper by Cook et al and you will see what the consensus is really about. Not that much shocking facts. Human activity is creating greenhouse gas and this impacts the global climate.
So basically I would advise any skeptic to read and think for themselves. Don't accept what is pre
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rocketeer at 04:09 AM on 29 June 2017Climate scientists just debunked deniers' favorite argument
I don't think I have ever seen a model projection for the upper and intermediate ocean temperatures. Does one exist? Since that is where 90% of the heat goes, and it seems rather immune to internal variation and other non-radiative forcings (possibly due to the ginormous mass involved) it would seem like this would be easier to predict. In general, I think this data should be presented to the public more frequently.
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michael sweet at 03:39 AM on 29 June 2017We are heading for the warmest climate in half a billion years
Art Vandelay,
While humans could build structures and survive, what would help all the agricultural animals left in the open? Not to mention that crops fail at high temperatures. While people can live in buildings they have to grow food.
Many scientists think the dangers of geoengineering exceed the benefits. Sulfate aerosols, the most common "solution" proposed, causes severe drought. Does that really solve the problem or just trade one problem for another? It is much more cost effective and safer to pollute less and reduce AGW than to pollute more and try to use untested technology to get out of a problem.
You complain elsewhere that people concerned about AGW are "advocates that overstate the effectiveness and avoid mentioning potential down-sides ." Perhaps you need to look in the mirror and see how much that applies to you.
Please provide a citation to support your claim that "The risks of geo-engineering may be high but still much lower than doing nothing." Most of the analysis I have seen is the opposite.
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John Hartz at 03:29 AM on 29 June 2017Climate scientists just debunked deniers' favorite argument
Recommended supplemental reading:
Study: Why troposphere warming differs between models and satellite data by Zeke Hausfather, Carbon Brief, June 21, 2017
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michael sweet at 02:50 AM on 29 June 2017SkS Analogy 8 - I'll take the specialist
Art Vandelay,
Billions of dollars are wasted in the USA screening for prostrate cancer. Doctors make billions of dollars treating the poor souls who screen positive. Millions of American men have been rendered inpotent or incontinent by this treatment. Studies show that few deaths are prevented by all this treatment. In Europe, where the health system focuses on patient outcomes and not the profit of doctors, they have made much less use of the PSA screening test and have better overall health outcomes. The surgeons do not make as much money.
The fossil fuel industry has cried wolf many times during my lifetime over environmental regulations causing economic damage. You need to find a new analogy.
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ubrew12 at 01:03 AM on 29 June 2017Climate scientists just debunked deniers' favorite argument
Christy: "the models... would be inappropriate... in predicting future changes in the climate or for related policy decisions." Compared to what? Christy's intuition? Lamar Smith's faith that the future will be unlike the past? Inhofe's 'God is still up there'? The models are all policymakers have because the 'other side' of this debate steadfastly refuses to put together any models (or refuses to share the knowledge that they put them together, i.e. Exxon 1980). You would think an industry with a 22 trillion dollar stake in the outcome of this debate would be able to afford a better pointer to our climate future than James Inhofe's snowball.
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peter7723 at 23:07 PM on 28 June 2017Electric Cars are the Missing Link to a Zero Carbon Energy Grid
I installed a 3kW Solar PV system and needing a new car, purchased a plug-in hybrid. In my latitude, 38°S, comparing the year before with the year after, I reduced my annual petrol consumption from 1200L to 190L, saving $1,300. The PV system meant that my electrical energy did not increase. As for CO2 emissions, the PV system displaced 4MWh per annum. The emissions intensity of petrol is about the same as that of the electrical energy generated from brown coal. The oil industry should be worried.
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Swayseeker at 22:43 PM on 28 June 2017New study confirms the oceans are warming rapidly
If we are going to be hotter and more humid then wet bulb temperatures could reach dangerous levels. One cannot cool oneself down below wet bulb temperatures by means of sweating, so one must reduce temperatures or humidity. One can reduce humidity by having a lot of convectional rain and "Understanding the sky" which can be found on the Internet tells us why the clouds are higher in the tropics than at the poles. Most of the tropical rain is conectional and this has "dried out" the atmosphere a bit, making dew points lower. Using Espy's equation tells us that with lower dewpoints (resulting from lower relative humidity) cloud bases are higher. 125 (T-Tdew) is a larger number if Tdew is smaller. Using solar air heaters on every rooftop can dry out air by continuous convection and rain. This will lower wet bulb temperatures.
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Bob Loblaw at 22:41 PM on 28 June 2017Models are unreliable
NorrisM:
With a legal background, and experience in trying to assess the credibilty of different sources, one thing for you to look for is inconsitencies in a position. Skeptical Science has a summary page listing contradictions in the so-called "skeptical" view of climate change.
Another issue to keep track of is how often someone expresses complete certainty on something. Generally, you will find that the science of climate change has a lot of "ifs" and "most likelys" - sources of error are discussed at length, and implications of uncertainty are noted. In the so-called "skeptical" view, you will often find very definitive statements (that often contradict other definitive statements). In science, admission of uncertainties is a strength, not a weakness.
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Glenn Tamblyn at 19:49 PM on 28 June 2017Models are unreliable
NorrisM
Firstly, for you as a lawyer, whose principle skill is the use of language...
"Can we not come up with a less pejorative term than "climate change denier" with all its connotations when literally none of the Curry, Christy et al group deny that the world is getting warmer."
This is standard rhetorical technique which I presume you would be adept at slicing through in a legal context. The term 'climate change denier' covers a range of differing 'denials' and by claiming it is being ascribing to one subset of of this 'population', aren't you are engaging in rhetoric.Next, the purpose and function of climate models. They are, really, no different from weather models. Used to produce the weather forecast.
Climate models work at a coarser resolution than weather models but essentially attempt to produce differing results. A weather model takes what the weather is today and attempts to determine what the weather will be x days from now. In principle, exactly. Well, sort of...
A climate model, being coarser, has a snowflakes chances in hell of doing this. One run of a climate model will be significantly random. And another run of a climate model, with slightly differing starting conditions will also be significantly random.
What if we do many runs of the climate model, each with slightly differing starting conditions? Each run is different. But what does the average of many runs look like? Well this starts to have a pattern, an order to it.
Although each run differs, their average is much less chaotic. Because the underlying climate does vary in a modestly predictable way. The average has predictability.
But that does not mean that the actual day to day evolution of weather over climate timescales will accurately follow this average trend. Because day-to-day weather is chaos superimposed over an underlying order. And since we can't easily predict the chaotic component, the actual weather data will not ever match the climate exactly.
So we can't expect weather to progress with the regularity that the climate averages suggest. -
scaddenp at 19:08 PM on 28 June 2017SkS Analogy 8 - I'll take the specialist
"Conversely, cancer treatments also don't have advocates that overstate the effectiveness and avoid mentioning potential down-sides. So it cuts both ways."
I think you will many to dispute that, but rather offtopic.
I find your view of humanity depressing. Glad I dont live where you live.
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Art Vandelay at 15:22 PM on 28 June 2017SkS Analogy 8 - I'll take the specialist
Conversely, cancer treatments also don't have advocates that overstate the effectiveness and avoid mentioning potential down-sides. So it cuts both ways.
I agree though, with the exception of people in their 20's or younger, most of us will probably avoid the dire consequences of climate change. Speaking only for myself here, but I think the best thing that I can do for my children and future grandchildren is to leave enough money to help them live as comfortably as possible and in the best place possible, though I accept that that's a selfish motivation. But I guess that's my point anyway. Most people will act out of self interest before collective interest, and most people will plan for the short term before they plan for the medium or long term.
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scaddenp at 14:42 PM on 28 June 2017SkS Analogy 8 - I'll take the specialist
Fortunately most cancer treatments dont have do-nothing advocates exaggerating the cost of the treatment so they dont lose market share. In your brothers case another interesting analogy comes up. Suppose instead it was your 3 year old son. What route would take and whose advice would you trust about likelihood of surviving till a better treatment comes? Mostly we are making decisions about what a future generation would face.
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Art Vandelay at 10:11 AM on 28 June 2017SkS Analogy 8 - I'll take the specialist
Climate change is more like a cancer than an injury though, taking a long time to present definite symptoms and requiring a variety of invasive treatments over a long period of time.
There are many cancer sufferers who decide not to undertake the treatments due to the high costs and known painful side-effects, particularly if a successful outcome has a low probability.
Similarly, with climate change mitigation, people will only be encouraged to pay for the treatments if there's a high probability that they will cure the disease, and they need to be confident that the treatments themselves don't create many years of misery. I have a brother with a rare form of Leukemia that could be treated today with highly invasive and high risk treatments, but he's chosen a path of non invasive and low risk measures that will hopefully buy him enough time to still be alive when better and safer treatments that offer a cure are available.
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scaddenp at 09:43 AM on 28 June 2017CO2 lags temperature
"Zero" on the graph is not really present day. At no time on that graph does CO2 ppm exceed 300pm. We are now over 400pm. The last time earth was at 400 was in the pliocene when it was too warm for ice age cycles.
And yes, there are long period cycles at work - the Milankovich cycles. A complex series of feedbacks accompany the ice age cycle. As ice extends down on NH, swamps freeze over, vegetation changes, sea level drops exposing more land for plant colonization, and as temperature of ocean drops, its ability to hold dissolved CO2 increases. All work to reduce CO2 in atmosphere. Works in reverse when orbital forcing changes the other way.
In summary you cannot change the temperature of the planet without also changing the CO2 concentration the atmosphere which then acts as a feedback to amplify that change (and to make NH driven changes into global changes). However, these are also very slow feedback systems, operating over 100s to 1000s of years (because it takes nearly a 1000 years for ocean to equilibrate). Eventually we will see these feedbacks cut in from our forced change to climate but not in this century to any great deal.
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Art Vandelay at 09:21 AM on 28 June 2017We are heading for the warmest climate in half a billion years
Humans can adapt in part, such as building climate controlled cities, such as the one proposed in Dubai, but I'm sure that geo-engineering will be implemented if the summer temperatures start to exceed 40C on a regular basis in large mid latitude cities. The risks of geo-engineering may be high but still much lower than doing nothing.
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Tom Curtis at 08:58 AM on 28 June 2017Human CO2 is a tiny % of CO2 emissions
Danilushka @309, the most recent plateau in temperature and CO2 level shown in the graph of the Vostock ice core data (which is called the Holocene), has lasted over 10 thousand years. Over that period, CO2 levels have increased from about 260 ppmv to about 280 ppmv just before the industrial revolution, ie, an average increase of 0.002 ppmv per annum. Since the industrial revolution, CO2 concentrations have increased by 120 ppmv over approx 270 years, or 0.444 ppmv per year, or 222 times as fast.
Needless to say, over 10 thousand years is "thousands of years".
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Danilushka at 08:18 AM on 28 June 2017Human CO2 is a tiny % of CO2 emissions
Please reconcile your statement in the first paragraph, "Before the industrial revolution, the CO2 content in the air remained quite steady for thousands of years." with the graph in the article entitled "CO2 lags temperature - what does it mean?" Figure 1: Vostok ice core records for carbon dioxide concentration and temperature change.
Figure 1's CO2 concentrations don't look quite steady for thousands of years at all. Not even close. Am I missing something?
https://skepticalscience.com/images/Milankovitch_Cycles_400000.gif
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Danilushka at 08:09 AM on 28 June 2017CO2 lags temperature
I am just trying to understand this so please bear with me. Looking at the series of temperature changes (3 in all in Figure 1 Vostok ice core records) in the graph of CO2 versus global temperature, there seems to be a long-period cycle at work. Or there was perhaps if man has changed things. It seems the current peak is actually lower than the first, despite man's injection of CO2. It is hard to separate the CO2 from the temperature for this recent peak due to the long period in the graph and large time scale.
Is there a graph with the same axes covering a shorter period such as the width of the previous cycle? It would also be interesting to see each of the 3 cycles split out with better resolution to see if this time, as early in the cycle as it is, is different and, if it is, by how much and how it is trending. I suspect this might be available somewhere, but I am new here and not sure how to find it or even ask so please forgive my lack of information on this.
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scaddenp at 07:52 AM on 28 June 2017New study confirms the oceans are warming rapidly
So those trying to blame oceans for global warming would appear to be in same boat as those claiming you could reduce deficit and increase government spending while cutting taxes?
Just like money, heat has to come from somewhere.
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nigelj at 06:41 AM on 28 June 2017We are heading for the warmest climate in half a billion years
A swamp like hot, wet climate will be an incubator for all sorts of tropical diseases, just at a point where we are having problems with antibiotics. And dont kid yourself technology will solve this, as new antibiotics will develop the same problems.
Some people argue a warmer climate is a good thing, but it has plenty of downsides. Heatwaves combined with higher humidity doesn't sound like a good combination, and this is costly to adapt to.
My country will get more rainfall, and has already seen an increase in rainfall. The trouble is this is mainly falling in the one geographical location where it's of no use to either electricity generation or agriculture.
This giant, unintended experiment with climate is high risk, and solutions like geoengineering would be high risk, ambulance at the bottom of the cliff approaches. But thats typical of humanity in so many ways, as our record in prevention isn't so great.
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NorrisM at 04:01 AM on 28 June 2017Models are unreliable
Tom Dayton, Eclectic & MA Rodger. I would like to thank all of your for your comments. I think I have to spend more time reading the full thread both for this topic as well as on questions of MWP etc. I think that I will withdraw from any further comments until I have at least read the full thread on this topic (this could be a long time!).
As a lawyer and not a scientist, I find the best way to come to a conclusion is listen to both sides similar to the process in determining any litigation (I am actually a business lawyer not a litigator). For this reason, my plan is to stay on this website and also the Nigel Lawson GWPF site. I actually have never even looked at the Skeptical Science website. I think I can "filter" things sufficiently to read postings on both sites.
The information on Steve Koonin is quite interesting given his statements in the transcript of the APS panel hearing where he professes surprise a number of times on what he was hearing. I thought I was reading the questions of independent physicists who were trying to get at the facts (I just about said "truth"). But I do commend that transcript to all of you, if only to hear how these significant IPCC climatologists respond to the questions.
But one suggestion to the editor of this website. I think that "ad hominen" comments on the persons contributing to this website should be fully deleted and never appear at all on the website. Just "stroking them out" but allowing everyone to read them just encourages those kind of comments to be made. I do find that the proponents of anthropogenic global warming seem to be much more in "attack mode" than the other side. Can we not come up with a less pejorative term than "climate change denier" with all its connotations when literally none of the Curry, Christy et al group deny that the world is getting warmer.
This term "fake skeptic" is awfully close to "fake news". Is it recently invented since the advent of Trump?
Having said all of this, the recent post today indicating that Stephen Hawking is onside and part of a new organization gives me a significant degree of comfort. Reading his History of Time was a challenge but I got through it. Unless I have missed another YouTube, I was very disappointed with the Neil DeGrasse Tyson video explaining global warming because it is so simplistic and does not explain any of the challenges in trying to "predict" future changes in the climate. I appreciate why he has done this, reaching for the lowest common denominator amongst the public, but I think scientists do have a responsibility to qualify absolute statements. Otherwise, they move into the political arena which then undermines the confidence the public has in their scientific statements.
In any event, thanks very much for all of your comments. Lots of reading ahead of me.
Moderator Response:[DB] "This term "fake skeptic" is awfully close to "fake news". Is it recently invented since the advent of Trump?"
The term "fake-skeptic" has been used in this venue since at least 2010. The denial of the science by the venues you note is well-established over the years.
[PS] Your "truth search" understandably seems to be about determining the reliability of witnesses. How many bits of GWPF propoganda, misinformation and denial would we have to demonstrate to you before you decided they were unreliable witnesses?
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Art Vandelay at 01:16 AM on 28 June 2017Explainer: Dealing with the ‘loss and damage’ caused by climate change
OPF@25, you say, " I disagree as passionately as is possible in text to the following claim: "Ultimately, it's emisisons per square foot or meter of land that a country will be paying for."
People, not land area, are causing the problem. The accumulation of the per-person impacts of everyone in a nation, through the entire history of that nation, make up that nation's total impact. Land area is irrelevant."
I belive we are actually in agreement. My point was that people (population) is what matters, because it's people that create emissions. A country such as Australia has a relatively small population of big emitters, but if every country in the world had the same population density and emissions per capita as Australia, there would be no global warming problem at all. Conversely, if every country had the same population density and emissions per person as India (2017) there would be a very substantial global warming problem. Ultimately, the world can tolerate some amount of (equivalent) CO2 emissions per square mile or km of land, so in my view it should be the responsibility of each sovereign government to manage their population and emissions per capita within a taget limit based on total land area. This would force countries such as Australia, who want a big population, to become sufficiently CO2 efficient to support it. Likewise , countries with big populations would be encouraged to reduce or stabilise population levels.
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MA Rodger at 20:00 PM on 27 June 2017Models are unreliable
NorrisM @1047,
A big long comment from you setting out a lot of stuff. Can I home in on the things you describe as "what also troubles me in everything that I have read so far on climate change." (As you say it is off topic for the thread but...)
(1) The Mediaeval Warm Period. This you describe as being "at least 200 years in at least Greenland and Northern Europe close to or equal to our present temperature." The temperature at the top of Greenland can be reconstructed from ice cores with some accuracy. GISP2, for instance shows results like this graph and some will take the last few thousand years of this graph as proof that recent warming is trivial when compared with previous centuries, as this SkS post describes. Yet the most recent GISP2 data dates from 1855 and when you graft on modern temperature data things look a whole lot different. The idea that Greenland experienced temperatures "close to or equal to our present temperature" is not borne out by the evidence.
2. "During the 1600's and 1700's there was ... skating on the Thames." We do have the CET Central England Temperature record stretching back into the 1600s, temperatures recorded a few dozen miles up the road from the Thames at London. This shows seriously cold winter month have been occuring occasionally throughout the record with the last occuring in 2010. History tells us that Ice Fairs were rare events and they do coincide (almost always) with these exceptional cold CET months. Ice Fairs stopped not because of a Little Ice Age ending or because of global warming but because the old London Bridge was demolished and the banks of the river were embanked. It's all a bit nerdy, but ancient accounts of the Thames freezing continue back in time and continue through the Mediaeval Warm Period (prior to the bridge being built) and are even found for the centuries called by some the Roman Warm Period.
3. You are on much safer ground suggesting that reconciling the temperature record and climate forcing in the first half of the 20th century is not straightforward but very much less safe with the so-called hiatus. There is a lot of comment on these elsewhere within the SkS site. You do raise the idea that if the hiatus was the product of La Nina sucking the warming from the atmosphere and down into the ocean depths. (It is not controversial to state that the years 2007-13 saw lower global temperatures due to La Nina and withut these years the so-called hiatus is truly a non-event.) From this you speculate whether it was potentially the oceans warming the atmosphere 1975-98. You are not the first with such speculation. Bt if there was such a warming from the oceans, there would be evidence of it in the Ocean Heat Content data as it takes a lot of heat to both warm and keep warm the atmosphere. The level of heat required would certainly have to be evident in the OHC data. It is not evident.
Moderator Response:[PS] Thanks for contribution but it would be more appreciated if you had followed the request to put it on the correct place since MWP is offtopic here.
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Eclectic at 18:15 PM on 27 June 2017Models are unreliable
NorrisM @1047 , if I may add some background to Tom Dayton's posts :-
When considering climate models, it is well to remember that the models are based on the physical realities of this world.
And the most basic of relevant points, is that the natural greenhouse effect from CO2 etc. has been "artificially" (anthropogenically) pushed higher by the addition of fossil-origin CO2 to the atmosphere. The result is that the world is warming up — it is gaining heat at the rate of approx. 2 watts per square meter. (Which may not sound very much : yet if you think it through planetwide and decades-long, then it represents a major problem for this planet.) Also, if you think it through (regarding where that heat is going and how it moves about within the system of the planet) then you will realize that a pause or hiatus is simply not possible until such time as the system eventually reaches equilibrium (in 2 or 3 centuries' time).
Therefore if Koonin says there is a real "Hiatus", then he talks nonsense.
If you are a Black-Letter lawyer, you will wish to examine "fake-skeptic" comments without considering their provenance or any ad-hominem aspects. Yet as a pragmatic man-of-the-world lawyer, you will wish to take into account the background information regarding the four protagonists you mentioned [Koonin, Christy, Curry, Lindzen], when you come to assess their evidence.
And you will be aware of human frailties — particularly that frailty called "Motivated Reasoning" : where even very intelligent people (such as Koonin) do bend their rationality and end up deceiving themselves. And doing so, very staunchly! And with apparently honest demeanor!
Climate science is a large area, where you can educate yourself considerably — and if you do so, you will find yourself in agreement with the extensive and almost unanimous consensus of experts (e.g. the U.S. National Academy of Sciences; the U.K. Royal Society; the Vatican's Pontifical Academy of Sciences; and dozens more of peak scientific bodies). All in consensus about Global Warming. Indeed, there is only a score or so of Koonins, Christys, Currys, and Lindzens who hold an outlier position in disagreement with the overwhelming preponderance of scientific experts. And as you yourself gain education in climate science, you will understand that these 4 protagonists, despite their intelligence, have all managed to make a very poor judgment of the actual position. And that, as you look beyond their rhetoric, you will find that their apparently scientific arguments are empty and false.
How is it possible for 4 intelligent people to be so very wrong? It is because their emotions have pushed them into motivated reasoning. Motivated reasoning by Koonin / fundamentalist religious bias from Christy and Lindzen / and something less clear, from Curry [about whom you need ask: Cui Bono ].
In the strictest sense, these four are not being scientists — because they have allowed their emotions to override their dispassionate intellects.
They have muddied the waters and confused your understanding of the significance of models (and of the physical realities).
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Tom Dayton at 12:48 PM on 27 June 2017Models are unreliable
NorrisM, you asked
Is it “solid physics” that:
1. Water vapour will in fact increase as modelled?
2. Water vapour will cause the predicted additional increase in temperature by a factor of 2 to 3 times?Answers: Yes. I assume you are familiar with the concepts of relative and absolute humidity, at least from weather reports you've read and seen your entire life. Perhaps you've noticed that cold air (e.g., winter) is drier than warm air (e.g., summer). For more details, read the Basic and then the Intermediate tabbed panes here.
Moderator Response:[PS]"In addition, water vapor concentrations have increased throughout the troposphere at about 1.2% decade−1 since the ERBE period (Trenberth et al. 2005, 2007b). " from here. Also see Clausius–Clapeyron relation for seriously settled science. Water vapour is not the only feedback.
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Tom Dayton at 12:41 PM on 27 June 2017Models are unreliable
NorrisM, your claim
The models predicted that our temperature would increase on a linear basis. There were no “waves” in the models.
is incorrect.
All the models projected (not "predicted") inconsistent ("wavy") temperature increase. None projected monotonic ("linear") increase. The mean of models usually is shown in graphs, but all the individual model runs that contribute to that mean are "wavy." For ease of viewing, sometimes graphs of climate models show only the models' mean, or show the individual runs' spread as a shaded area. But the actual runs look like spaghetti.
We do not expect the actual temperature to fall exactly on the "ensemble mean" hindcast and forecast, because that mean has far too little variability. In fact, we expect the temperature to have wild ups and downs as you see exemplified by the orange and blue skinny lines in Figure 2 here, because we expect there to be El Ninos and La Ninas, variation in solar radiation, volcanic eruptions, changes in human-produced aerosols due to varying economic activity, and a slew of random and semi-random factors. It would be downright shocking if actual temperature followed the ensemble mean, because that would mean all those variations in forcings and feedbacks were far less variable than we have observed so far. So we judge the match of the real temperature to the projected temperature by whether the real temperature falls within the range of the entire set of individual model runs. Even so, we expect the real temperature to fall within that range only most of the time, not all of the time. The range you see drawn as a shaded area around the ensemble mean usually is the 90% or 95% range, meaning the set of individual model runs falls within that shaded range 90% or 95% of the time. That means, by definition, we fully expect the real temperature to fall outside that range 10% or 5% of the time. So occasional excursions of the real temperature outside that range in no way invalidate the models, when "occasional" means 10% or 5% of the time.
Moderator Response:[PS] An example graphic of real output of models and discussions is here. Realclimate also has a FAQ on models - written by the modellers themselves so not heresay.
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One Planet Only Forever at 12:06 PM on 27 June 20172017 SkS Weekly Climate Change & Global Warming News Roundup #25
New news report in the NYTimes.
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Tom Dayton at 11:40 AM on 27 June 2017Models are unreliable
NorrisM, initially I'm going to assume you are who you claim to be, though the content of your post makes me suspicious--very suspicious--that you are one of SkepticalScience's fake-skeptic, trolling, chronic sock-puppeteers, and one in particular.
Your statement
The APS panel consisted of six (6) arm’s length physicists (with no axe to grind) chaired by Steve Koonin who were asking hard questions of both sides. What actually struck me as very astounding was how honest Koonin was about his previous lack of understanding as to how uncertain climate science is owing to the uncertainties underlying the climate models.
is incorrect. Steve Koonin is a notorious fake skeptic, who has both the background and the subsequent, repeatedly delivered, information to know that most of what he says and writes is factually and drastically incorrect. Christy has and continues to make claims that are factually incorrect, and is motivated primarily by political and religious beliefs. Christy's partner in crime is Roy Spencer, who is a member of the Cornwall Alliance that claims human-caused global warming is impossible because God promised Noah there would not be any more floods. Really. LIndzen's pet theory about the "iris" mechanism that self-regulates the Earth's temperature conclusively and repeatedly has been proven wrong (obviously, since Earth's temperature has varied drastically--Snowball Earth, ice ages,...) but that has had no effect on his opinion, and he very much resents and takes personally the criticisms. Curry once was an adequately productive climate scientist, but for reasons I won't speculate on here, has become quite the opposite.
Moderator Response:[PS] That is uncalled for tone. I know all too well how tiring the denier trolls are but polite and reasonable enquiries are to be encouraged, as are substantive responses.
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NorrisM at 08:59 AM on 27 June 2017Models are unreliable
I would first like to state that I have finally found a website that is balanced on this very emotional issue. I also want to thank SemiChemE and Tom Curtis (along with a few others) who have engaged in a very fascinating discussion on climate models.
My intention is to pose a question on climate models in keeping with this blog, however because this is my first post, I would like to explain my background. I am a lawyer by training and have a very limited base in physics (took Latin in Grade 12 rather than physics) although I always did well in science. I will also disclose that I do have an involvement in the Canadian oil and gas industry notwithstanding that I live in Vancouver, BC.Ever since the issue of global warming came to the fore in the late 1990’s and since, I have to admit that I have tended to accept the “scientific consensus” if only because I had no reason to question it. Climategate shook my confidence in 2009 but if Neil DeGrasse Tyson still believes that the principal causes are anthropogenic then far be it for me to question it. However, it always seemed logical to me that a first step in reducing the effects of CO2 should be to move from oil and coal to natural gas (especially for electrical generation) which puts about one half of the pollutants into the air compared to coal and oil. After spending enough holidays in France, I have also thought that a switch to nuclear energy made more sense than disfiguring our planet with massive wind turbines and great areas of solar panels. Driving from LA to Palm Springs is not a pretty sight. But I do appreciate that there are real concerns relating to disposing of nuclear waste and issues of terrorists getting their hands on nuclear fuel. However, someone as significant as James Hansen believes that we will not achieve our goals without a turn to nuclear energy.
In any event, my recent interest in the causes of global warming really came about because I have two sisters who are just about no longer on speaking terms owing to their disagreements on global warming. When one sister called me asking where I stood on climate change and if I truly believed that this was all a “global conspiracy of the left” to increase taxes and government control over our lives, I promised her that I would buy some books on both sides of the argument and get back to her. Needless to say, I do not believe in conspiracy theories of any sort.
So the two books I located were The Science & Politics of Global Climate Change by Dessler and Parson and Climate Change the Facts edited by Alan Moran.
By the time I was finished with Dessler’s book I was convinced of the science. Then I read the essays in the Moran book and found myself at least questioning some things.I actually then went back and re-read Dessler’s book to see where the gaps were. I have to say that when I found that Mark Steyn had an essay in the Moran book I almost did not read the book because of his extreme views. Just to make my political views clear, I think Donald Trump poses a major threat to liberal democracy in the US and to the world in many ways. But it does look like the US institutions may be able to withstand him and his cohorts. I also follow Sam Harris’s podcasts “religiously”.
Since reading these two books I have largely pursued my research on the web even reading the submissions of the four climatologists on March 25, 2017 to the House Committee on Science Space and Technology.
Based upon Judith Curry’s reference in her submission, this led me to the most fascinating discussion of the topic of climate models by a panel of physicists formed by the American Physical Society (APS) which posed questions to six (6) well-known climatologists having “different perspectives”. Three (3) of them (Collins, Santer and Held) are IPCC climatologists and the other three (3), Curry, Christy and Lindzen are on the other side of the debate. This was the 2014 Workshop sponsored by the APS as part of its 5 year review of its Climate Change Policy Statement.
As a lawyer, I have to admit that if I treated (i) the IPCC 2013 Assessment as an appellate lawyer’s factum, (ii) the Workshop Framework posed as questions from the bench, and (iii) the 600 page transcript of the panel hearing as the “give and take” between the judges and lawyers during the oral argument of the appeal, I would have predicted a “win” for Curry, Lindzen and Christy and a “loss” for Collins, Santer and Held. Both the Workshop Framework questions and the transcript are on the APS.org website. Just search “Climate Change Statement Review”. If anyone has read any legal transcript of a hearing you know it is a simple read so don’t be put off by the “600 pages”.
The APS panel consisted of six (6) arm’s length physicists (with no axe to grind) chaired by Steve Koonin who were asking hard questions of both sides. What actually struck me as very astounding was how honest Koonin was about his previous lack of understanding as to how uncertain climate science is owing to the uncertainties underlying the climate models.
This panel hearing took place in February 2014. By November 2015, the judgment of the Board of Directors of the APS was in. The connection between increases in CO2 and global warming was “compelling”. However, the APS did acknowledge that there were significant uncertainties in the science and urged sustained research in climate science.
Where my comparison with an appellate hearing breaks down is that no appellate court would render a significant judgment without providing its reasons. We do not get any reasons from the panel as to why it recommended to the Board of Directors (as I assume it did) that the APS “stay the course” with its policy statement notwithstanding the serious reservations you could see in Koonin’s and other panel members questions to Collins, Santer and Held and the weak answers provided by them. The IPCC climatologists in effect admitted that Christy’s now famous chart showing how far apart the average predictions of the climate models were from actual observations was “old information” and did in fact represent the existing state of models predictions versus observations. See Santer page 504. The IPCC climatologists effectively said that they could not trust the observations! Koonin’s rhetorical question to Held to this "observational" response earlier was: “So the ability then to reproduce historical data is neither necessary or sufficient to predict the future. Is that what I understand?” See page 453 of the transcript. Held effectively avoids answering the question. See page 454. Read it yourself and see if you disagree with my view of his response.
So here is my question.
From everything that I have read so far, other things being equal, a doubling of CO2 in the atmosphere from pre-industrial levels of CO2 of around 280 ppm to 560 ppm will increase the global surface temperature by about 1 to 1.2C and the balance of the predicted range of 1.5C to 4.5C of the IPCC 2013 Assessment is based upon “positive feedbacks” resulting from increased water vapour that is assumed will form arising out of the 1C increase by CO2. I accept (or understand) that the 1C increase is “solid physics” or “hard science”.
Is it “solid physics” that:
1. Water vapour will in fact increase as modelled?
2. Water vapour will cause the predicted additional increase in temperature by a factor of 2 to 3 times?Although this next observation is not specifically focused on the climate models, what also troubles me in everything that I have read so far on climate change is the following:
1. The Mediaeval Warming Period had temperatures for at least 200 years in at least Greenland and Northern Europe close to or equal to our present temperature.
2. During the 1600's and 1700's there was a "Mini-Ice Age" when they were skating on the Thames. We were just coming out of this cold period at the beginning of the American Revolution (good timing).
3. From 1990 to 1940 we experienced about .3C warming; then from 1940 to 1975 there was a levelling off or cooling period; then from 1975 to 1998 we experienced .5C warming; and then there was a levelling off (termed the “hiatus” by the IPCC) of now about 17 plus years that may or may not have ended in 2015 (El Nino event 2015-2016). I appreciate that 1998 was an El Nino year but the IPCC 2013 Assessment recognized the “hiatus” up to that time.
If climatologists cannot explain why these other warming and cooling periods occurred which, other than the 1975-1998 period, were primarily or completely caused by natural climate change, then why can they so confidently claim that this one warming period was primarily caused by the CO2 rise? Just because there was a concomitant rise in CO2? What about the rise of CO2 from 1950 to 1975?
The models predicted that our temperature would increase on a linear basis. There were no “waves” in the models. I guess based upon Michael Mann’s most recent testimony the most recent peer reviewed papers are now suggesting that we will be going up in steps or waves. Can we now expect that the new models with show the steps or waves?So where did the “warming” go during this “hiatus”? If the answer is into the oceans, then why did the “warming” not come from the oceans during the period 1975-1998? Could we have had a cooling period during the “hiatus” that offset the warming from CO2 during this period? What are the impacts of a decrease or increase in low clouds caused by natural factors which impacts the amount of sunlight hitting the earth? Because of computer capacity issues, we can only make “parameterizations” of clouds in the models. These are the kinds of questions that make me question the validity of the models.
When we talk of the difference between weather and climate we say we cannot predict weather but we can predict climate because we know that next July it will be warm. But why do we know that? Not from models, from observation. If observations and models do not correspond, when do we admit that the models do not have sufficient predictive value to be relied upon? It is OK for science to say “we just do not presently understand the science sufficiently to make reasonably accurate predictions”.
On the other hand, here are the major science societies of the world like the APS, the US National Academy of Sciences and the UK Royal Society coming out strongly in support of the proposition that man-made global warming is a serious problem and is going to get worse. My worry is that they got on a band wagon in the early 2000’s before the “hiatus” was apparent and they now find it very difficult to get off even when they see that these models are not predictive.
I apologize for such a long-winded initial blog. If you think I have to reduce it, please advise.
Moderator Response:[PS] Welcome to Sks. We really like to keep things on topic, (see the comments policy) so we would prefer you put your questions about MWP on the appropriate thread after first reading the article. (your questions are pretty well answered in the IPCC WG1 as well). Ditto, other questions not about modelling. Could responders please stick to modelling questions only on this topic? Thank you for your cooperation.
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