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    Regarding natural variation. The imbalance is positive meaning that natural variation is negative. This is seen as a lag of the global surface temperature behind the (still rising) equilibrium temperature. This lag is largely because of the ocean's thermal inertia so the surface temperature can't keep up with the forcing rate of change because energy is also going into warming the deep ocean.

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    https://judithcurry.com/2018/12/15/week-in-review-science-edition-91/#comment-886599 Saves me restating it again.

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    Too small to measure - does that ring a bell?

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    Re: <i>"Well, Atomskiy, you can start here with point 21. The deficiencies of climate models are very well documented in the literature."</i> Then cite the peer-reviewed literature... ...Oh wait, you can't because you don't read it. And when I cite the literature, you willfully ignore it and make up excuses for dodging it (ex: whining that my citing it makes my posts too long). So actually cite the peer-reviewed literature. No, the Nic Lewis blog article you linked is not part of the peer-reviewed literature. Re: <i>"It would be helpful if you stopped the ad hominems and actually responded to the substance. You could start with the above very succinct points with literature references."</i> You don't know what an "ad hominem" is, and I'm not interested in your whining. You're simply complaining about tone, because you have nothing of substance to say. When you finally develop an genuine interest in the science, you can go read up on the evidence on positive feedback from clouds, consistent with climate models: <i>"Evidence for climate change in the satellite cloud record" "Observations of climate feedbacks over 2000–10 and comparisons to climate models" "Cloud feedback mechanisms and their representation in global climate models" "A net decrease in the Earth’s cloud, aerosol, and surface 340 nm reflectivity during the past 33 yr (1979–2011)" "Long-term cloud change imprinted in seasonal cloud variation: More evidence of high climate sensitivity" "Impact of dataset choice on calculations of the short-term cloud feedback" "A determination of the cloud feedback from climate variations over the past decade" "Climate variability and relationships between top-of-atmosphere radiation and temperatures on Earth"</i> (This is the part where you'll again whine about the length of posts, citation of posts by giving their titles, etc. so you can dodge evidence)

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    Jesus, Sanakan, I did not read your last comment in detail. The reason why is just sound judgment on my part. Let me just say that the scientific literature is voluminous. Quoting single sentences or paragraphs from it is just selection and I doubt you are a sound judge of the weight of evidence on complex issues. I've found that Lewis is good at summarizing and is truthful and provides context.

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    In addition its Christmas Eve. Merry Christmas and may you Sanakan keep its spirit in your heart the whole year.

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    Look at the picture again. The 30-year temperature started to skyrocket by 1980. Too large to deny. It's a rate consistent with the center of AGW's prediction. A stronger signal could not be asked for.

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    I bring this down here to highlight the partisan nonsense yet again. https://judithcurry.com/2018/12/15/week-in-review-science-edition-91/#comment-886612 <i>“Cloud feedback mechanisms and their representation in global climate models” </i> "Are the observed cloud changes solely a manifestation of natural internal variability or are they also a response to external radiative forcing of the climate system? We addressed this question by examining simulations from the Coupled Model Intercomparison Project Phase 5 (CMIP5) multi-model dataset17. Historical simulations included anthropogenic greenhouse gas concentrations, ozone, land-use changes, anthropogenic aerosols, volcanic aerosols, and solar output and thus represent our best estimate of the climate response to recent external radiative forcing (Extended Data Table 1)." But it is known that observed cloud changes are a manifestation of internal variation ( e.g. Loeb et al 2018, IPCC 2007, Myer et al 2019, Burgman et al 2017) - with global variation dominated by low level marine strato-cumulus in the eastern Pacific (Clements et al 2009). Physics involve Raleigh-Benard convection with open and closed cell cloud (Koren 2017). And we know that models miss internal variability - and really only react with sensitive dependence on initial conditions to forced changes. https://judithcurry.com/2018/12/15/week-in-review-science-edition-91/#comment-886450 Like most of these ill informed fanatics - it seems all or nothing with atomski. <i>“A net decrease in the Earth’s cloud, aerosol, and surface 340 nm reflectivity during the past 33 yr (1979–2011)” </i> Well yes - it is associated with low frequency internal climate variability (IPCC 2007, Wong et al 2006, Loeb et al 2018). <i>“Long-term cloud change imprinted in seasonal cloud variation: More evidence of high climate sensitivity”</i> "The large spread of model equilibrium climate sensitivity (ECS) is mainly caused by the differences in the simulated marine boundary layer cloud (MBLC) radiative feedback. We examine the variations of MBLC fraction in response to the changes of sea surface temperature (SST) at seasonal and centennial time scales for 27 climate models that participated in the Coupled Model Intercomparison Project phase 3 and phase 5. We find that the intermodel spread in the seasonal variation of MBLC fraction with SST is strongly correlated with the intermodel spread in the centennial MBLC fraction change per degree of SST warming and that both are well correlated with ECS. Seven models that are consistent with the observed seasonal variation of MBLC fraction with SST at a rate −1.28 ± 0.56%/K all have ECS higher than the multimodel mean of 3.3 K yielding an ensemble‐mean ECS of 3.9 K and a standard deviation of 0.45 K." https://notalotofpeopleknowthat.files.wordpress.com/2015/04/trend_thumb4.png Decadal change in sst are dominated by decadal changes in upwelling on the western margin of continents - especially the Pacific. <i>“A determination of the cloud feedback from climate variations over the past decade” </i> "Over this period, the short-term cloud feedback had a magnitude of 0.54 ± 0.74 (2σ) watts per square meter per kelvin, meaning that it is likely positive." The cloud 'feedback' is largely due to variable sst in the in the decadal to millennially variable Pacific state. <i>“Climate variability and relationships between top-of-atmosphere radiation and temperatures on Earth” </i> "Dessler [2010, 2013] noted that the short record is dominated by ENSO variations and used clear‐sky versus all‐sky radiation in reanalyses to estimate cloud radiation forcing involving several assumptions and a model. These papers build upon earlier studies that show the importance of ENSO and how convection, clouds, and upper tropospheric water vapor play key roles in feedbacks [Soden and Fu, 1995; Bony et al., 1997; Inamdar et al., 2004]. In Dessler [2013], computations were made of many components related to radiative feedbacks, from surface and atmospheric temperatures, water vapor, cloud, and surface albedo anomalies, converted using a “radiative kernel” to a TOA radiation anomaly." c.f. https://journals.ametsoc.org/doi/10.1175/JCLI-D-17-0208.1 - https://www.mdpi.com/2225-1154/6/3/62 I have bookmarked this - but while I am more than happy to slowly read in detail - it's not clear what atomski thinks the point is. About nearly anything really. It is clear than quoting titles of studies he seems less than familiar with - in what seems like a complete ignorance of the topic - and colored with a great deal of empty posturing about contrarions means very little indeed.

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    Re: <b>"Let me just say that the scientific literature is voluminous. Quoting single sentences or paragraphs from it is just selection and I doubt you are a sound judge of the weight of evidence on complex issues. I’ve found that Lewis is good at summarizing and is truthful and provides context."</b> More evidence-free whining from you. More pretending that the paper's aren't being cited by giving their titles. It's clear that you simply have no clue what the scientific literature shows, and just making excuses for the fact that the limit of your knowledge is non-peer-reviewed blog articles written by Nic Lewis. Sad. Let me know when you finally have an honest interest in the scientific literature, and the ability to actually read it.

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    frankclimate: Yes, I am familiar with the graph.. It is essentially the same as the Fig (a) plot that Richard Ellison had posted on Dec. 20. The problem with it is that it shows only negative forcings for aerosol emissions.. When they settle out, their forcings effectively become positive, since their removal causes temperatures to increase. This warming can be substantial, and is actually shown on the graph as the "total anthropogenic emissions" line, there being no demonstrable warming from greenhouse gasses (entirely hypothetical).. Any "peer reviewed" paper that does not consider the climatic effects of SO2 aerosols, and supports only the greenhouse gas warming hypothesis should be discarded. Harsh words, but provable.

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    "OK, so now what you call no-feedback is also the Planck Response. You have progressed. Your confusion arises because you don’t distinguish a feedback from a response." #jiminy The Planck response is calculated using only the temperature (Planck) feedback - it is of course purely theoretical as the planet responds in complex ways to forcing, warming, CO2 greening... https://judithcurry.com/2018/12/15/week-in-review-science-edition-91/#comment-886599 But there is a cultural meme here - reiterated with a strange and desperate obsession - along with the habitual and misplaced supercilious disparagement of 'skeptics'. "I’ve spent a fair bit of time hanging out with some of the hardcore climate deniers. And I think they’re very open about the fact that what brought them to this issue is not that they discovered a problem with climate science. It’s that they look at what the science is saying and they realize that if the science is true, it would upend their ideological project—because their ideological project calls for deregulation, austerity cuts, privatization of the public sphere, deregulated free trade. And if you just glance at the kinds of policies we would need in order to take the science seriously, it would mean strong regulations of the corporate sector; it would mean big investments in the public sphere to prepare ourselves for heavy weather and to lower our emissions rapidly. It would also mean transfers of wealth, which they’re not very big fans of. So they’re faced with the problem that either the science is true and their ideology is in deep trouble, or the science must be a vast conspiracy and there ideology is fine. And they’ve chosen the latter for obvious reasons. But I do believe they understand that if we were to take the science seriously it would require upending the neoliberal consensus." Naomi Klein Their problem is that the science of the complex dynamical Earth system is not as simple, certain or monolithic as they need it to be. Not much in Earth system is falsifiable in the traditional sense. But climate will shift again within the decade - if it is not happening now. This time the instrumentation is in place and it will unfold on prime time TV - like a slow motion train wreck of ambitions of social and economic transformation. They are hoping - those who have intimations of this multi-decadal variability - for the return of warming 'with a vengeance'. With solar modulated shifts in ocean and atmospheric circulation it cannot be strictly periodic at the decadal scale - and a centennial cooling phase in these natural systems is on the cards. Climate shifts bring catastrophe - in the sense of Rene Thom. But even then the pragmatic response remains the same as when I read the First Assessment Report as a relatively young hydrologist and environmental scientist. Energy innovation, energy efficiency, reduction of black carbon, surface ozone, sulfate, methane and CFC's and restoration of soils and ecosystems. Their other problem is that economically the world is locked into a growth cycle – despite any and all reservations and interventions.  A high growth planet brings resources to solve people and environment problems.  The clearest way to economic growth is markets – and the biggest risk is market mismanagement. The global economy is worth about $100 trillion a year. To put aid and philanthropy into perspective – the total is 0.025% of the global economy. If spent on Copenhagen Consensus smart development goals such expenditure can generate a benefit to cost ratio of more than 15. If spent on the UN Sustainable Development Goals you may as well piss it up against a wall. Either way – it is nowhere near the major path to universal prosperity. Some 3.5 billion people make less than $2 a day. Changing that can only be done by doubling and tripling global production – and doing it as quickly as possible. Optimal economic growth is essential and that requires an understanding and implementation of explicit classic liberal principles for effective economic governance of free markets. To be defended in a clash of values for which the climate war is a proxy.

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    Atomsk's Sanakan: <i>“none of the models can yet be said to have “passed” what are called “tests” or “stringent tests”.” </i> My fault. I was referring to models of mean surface temperature, but I did not make that clear. Of many predictions of all kinds that have been made, some outcomes conform at least semi-quantitatively to predictions. Is there a model that can be said to accurately forecast the next 20 year record of global mean surface temperature? Or the next 20 years of any large region such as, say, the Congo, Amazon Basin, Indonesia, or the rice-growing region of China? Has that model got a record of success forecasting those regions? The recent warming of the lower stratosphere was not predicted. It seems from your writing that you give no weight to unpredicted outcomes or outcomes that have not been accurately predicted.

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    Reblogged this on <a href="https://ididntasktobeblog.wordpress.com/2018/12/25/cliff-mass-victim-of-academic-political-bullying/" rel="nofollow">I Didn't Ask To Be a Blog</a>.

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    Matt, What is happening here is that you are basically right about climate model skill and there is plenty of evidence for that in the literature for example on the pattern of warming. The TLT divergence shown by RSS is another example. The mismatch between TLT vs. total column water vapor and model expectations is another. From first principles we know that there are thousands of possible output functionals. There are a number of parameters, perhaps O(100) to tune to match a few of these functionals like top of atmosphere radiation imbalance. Since the truncation and sub grid model errors are larger than the changes to energy fluxes we care about, there is no expectation that those outputs not used in tuning will be even close to right. The problem here is for CMIP5 for example everything pre-2005 is a hindcast and with tuning being not well documented and modelers being well aware of the surface temperature record, there is probably some tuning for that. Thus, its the other measures that are a better test of skill. Further, skill cannot be established by the qualitative things like "is the sign of stratospheric temperature change correct?" Thats a weak test. Sanakan is using a classical polemical trick of diverting attention from the obvious truth of your point by focusing on a single issue about the stratosphere where its hard to know if he is right or not. What he's talking about is largely irrelevant to real measures of model skill. And then there is the proof text quoting with no way to know if the quoted text is a fair representation or not. It's like arguing with a political operative who simply cannot fairly respond on any point. They focus on secondary or irrelevant points and quote their authority sources (selecting the parts they like) to justify themselves.

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    cerescokid, in this case the timing is given by solar activity. Being so close to the solar minimum, I would say that the maximum error is probably of one year. La Niña is very, very likely to come when solar activity increases rapidly after the solar minimum. Prof. Curry should take solar activity in consideration when her company issues ENSO predictions for the next 3 years.

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    Re: <b>"Further, skill cannot be established by the qualitative things like “is the sign of stratospheric temperature change correct?” Thats a weak test."</b> It's funny just how little people like you, matthew, etc. know about climate science, and just how little honest interest you have in learning. Sad, but telling. https://pbs.twimg.com/media/DtlbKAuXcAELNzu.jpg https://link.springer.com/chapter/10.1007/978-3-319-75140-5_26

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    Javier: <i>You might think there is no rational basis for this prediction, but the only way to know is to wait and see, isn’t it? </i> I did not mean to say there was no rational basis for the prediction, only that we should not now be acting as though we already know that the prediction was accurate.

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    "Recent scientific evidence shows that major and widespread climate changes have occurred with startling speed. For example, roughly half the north Atlantic warming since the last ice age was achieved in only a decade, and it was accompanied by significant climatic changes across most of the globe. Similar events, including local warmings as large as 16°C, occurred repeatedly during the slide into and climb out of the last ice age. Human civilizations arose after those extreme, global ice-age climate jumps. Severe droughts and other regional climate events during the current warm period have shown similar tendencies of abrupt onset and great persistence, often with adverse effects on societies." NAS 2002 Climate is the record of abrupt and more or less extreme change since before humans came to dominate the planet in the present interglacial. To deal with that requires building prosperous and resilient communities in vibrant landscapes. Doing that requires returning some of the 500 GtC lost from soils and terrestrial ecosystems since the advent of settled human communities (Rattan Lal). Along with energy innovation and efficiency and the reduction of black carbon, sulfate, surface ozone, methane, CFC's and other pollutants in the context of free markets and economic growth. Only rich economies can afford environments.

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    Atomsk's Sanakan: <i>You’ll just engage in Gish gallops, moving the goalposts, evasions, etc. to always avoid any evidence that shows you’re wrong. </i> You don't have evidence that goal posts have been moved. If they have been moved, where do they belong? The seven that I listed have been there for decades, at least since James Hansen forecast dire consequences in his Senate testimony..

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    https://www.sciencemag.org/news/2018/12/discovery-recent-antarctic-ice-sheet-collapse-raises-fears-new-global-flood "More certainty is on the way. Next month, the International Ocean Discovery Program’s JOIDES Resolution research ship will begin a 3-month voyage to drill at least five marine cores off West Antarctica. “That’s going to be a great test,” Carlson says. Meanwhile, he hopes to get his own study published in time to be included in the next United Nations climate report. In the 2001 and 2007 reports, West Antarctic collapse was not even considered in estimates of future sea level; only in 2013 did authors start to talk about an Antarctic surprise, he says. Research is due by December 2019. “We gotta beat that deadline.” " https://judithcurry.com/2012/08/03/post-normal-science-deadlines/#comments

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