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Thread: What is the reality of Climate Change?

  1. #1
    Copperknickers II's Avatar quaeri, si sapis
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    Default What is the reality of Climate Change?

    Few people these days deny that the climate is changing - over the past 30-50 years we've seen a variety of record-breaking events, which seem to be getting more and more frequent, especially the last 25 years. There are also many worrying trends of coastal erosion, natural disasters and melting ice caps which are causing concern. But I would like to talk about the confusion in what it all means and how we should interpret it. Without getting too deeply into the science, there seem to be some trends which should concern us principally and they are as follows. Let me know if I have missed anything out or got anything wrong:

    Long-term trends in geoclimatology: this is a favourite of climate change denialists. The Milankovitch cycles, combined with tectonic shifts in the position of the continents (and corresponding paths of ocean currents) seem to be largely responsible for the phenomenon of 'Ice Ages', one of which we are currently in, specifically an interglacial period between two nadirs of glacial activity. The trajectory over the course of the next 25-50,000 years is towards a glacial maximum which would replicate conditions when most of modern North Europe and Canada were covered in thick ice sheets and mammoths roamed the tundra. However, this is in large part dependent on us having polar ice caps in place (due to the feedback loop created by the Albedo effect which means massive-scale glaciation reflecting the sun's energy) and atmospheric carbon levels remaining largely stable. As such,

    1. We weren't scheduled to descend into another glacial maximum for quite some millenia yet, so the idea that we will be 'saved' from global warming by the ice age is for the birds, considering the next 250 years will bring unprecedented catastrophes even with conservative estimates of current warming trajectory.
    2. Most climatologists now agree that we will likely avoid the next glacial maximum altogether unless drastic changes are made to greenhouse gas emissions.

    Volcanism and oceanic emissions - Volcanism has caused massive extinction events in the past, including global warming on a terrifying scale. The Paleocene-Eocene thermal maximum was thought to have been caused by undersea volcanic greenhouse gas emissions. This means such drastic changes are entirely a natural part of earth's geological history, and so manmade global warming would not 'destroy the planet' as some alarmists claim, in the sense of making the planet uninhabitable by all mammalian species. However, the P-E thermal maximum is theorised to have increased temperatures by around 7 degrees. This is actually within the worst-case scenario estimates of manmade climate change, if carbon emissions in the developing world increase to match those of the developed world. And so while volcanism is not under human control, we risk seeing a climactic change of a magnitude comparable to some of geological history's worst climate disasters unfold during the next dozen generations. This means:

    1. If there were ever a massive volcanism event, we might see entirely natural global warming on a devastating scale. However this might not happen for millions of years and, while it should be of concern to the survival of the human race on planet earth in the long term, it's actually a threat of a magnitude not disimilar to what we may see in the very near future due to manmade action.

    Manmade C02 emissions This needs no further explanation, I think! Unless anyone wants to seriously claim that C02 emissions don't have a track record of leading to climate change, or that we aren't reducing large quantities of greenhouse gases. If so, go ahead, I'm game.

    Solar energy output - sunspot cycles are thought to cause changes in climate. They are sometimes thought to be largely responsible for the Roman Warm period, the Migration period dip, the Medieval Warm period, and the Little Ice Age. Some scientists predict a weaker cycle coming in the next decades, leading to a slightly colder climate. Climate change denialists claim that this will counteract global warming. However, the science behind all of this is HIGHLY questionable, and even if it were true, it would be a temporary respite which wouldn't have much of an impact on the baseline warming which carbon emissions seem to be producing, over the span of the next couple of centuries. I found a great article on this which you can read here.

    Unpredictable climactic feedback loops and counterloops - perhaps the best known of these is the disruption of El Nino and the Gulf Stream through melting ice, which are hypothesised to be leading to colder weather in localised areas. This has also been put forward by some as a 'saviour' from global warming. It is of course nothing of the sort - it will lead to more extreme weather which, even if not always 'warming', will still cause havoc and make some parts of the world more disaster-prone without helping other parts of the world much.

    Other environmental challenges which put society at risk - some things which have little directly to do with climate are nevertheless linked with manmade climate change through the 'manmade' part of the term. The felling of forests and other vegetation not only increases carbon emissions but also leads to degradation of habitats, leading to species loss (most notably the bee-pocalypse which poses a huge threat to agriculture) as well as the degradation of soil, leading to poor agricultural yields and desertification as well as flooding, landslides and other localised disaster risks. This feeds into climate change through exacerbating and complementing many of its effects. Urbanisation, poorly though-out engineering projects such as dams, and last but not least human population increase are environmental challenges which put huge localised pressure on things like water resources, again exacerbated by the warming climate.

    1. The environmental challenges will be felt most keenly in developing countries where agriculture is key to the economy and political stability. If agriculture, most notably the ability to provide livelihoods and food for citizens, suffers a collapse, we will see huge increases in the type of civil wars and mass migration which are already happening and already causing huge upheavals in the developed world.



    In conclusion, the pace of changing climate is quite simply not compatible with claims that long-term geoclimactic trends will somehow 'save' us, or that we are in the midst of hysteria surrounding short-term data being misunderstood and separated from the long-term context - there is clearly an acute crisis which will unfold over the course of the lifetimes of people currently alive, and which can only easily be stopped by reducing the amount of carbon going into the atmosphere as well as making drastic changes to how we use land and water. Combatting this will require, as far as I can see, coalescence around organisations like the UN and EU, or some kind of equivalent global cooperation, as ways of instituting global coordinated policy aimed at reducing the impact of all of the abiove. Next year will see a summit in my home city of Glasgow, and it will be among our last chances to avert a period of intense regress in living standards and wealth which will touch all of us. This is the reality of climate change.
    Last edited by Copperknickers II; January 11, 2020 at 05:41 PM.
    A new mobile phone tower went up in a town in the USA, and the local newspaper asked a number of people what they thought of it. Some said they noticed their cellphone reception was better. Some said they noticed the tower was affecting their health.

    A local administrator was asked to comment. He nodded sagely, and said simply: "Wow. And think about how much more pronounced these effects will be once the tower is actually operational."

  2. #2
    Daruwind's Avatar Citizen
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    Default Re: What is the reality of Climate Change?

    Sadly in theory only humanity can manage any last minute U-turn but it won´t probably happen. For each nation, the future is severe in little different way, for some it is living hell (Arabia - no drinking undeground water, high tempreratures ; India - pollutions, water problems, heat ; Indonesia - pollutions, heat, rising water) while for some it in theory can bring new golden age (Russia - Siberia thawing, access to north pole, northeast passage route between Atlantic/Pacific)

    Plus there is the whole "who will pay it question". Western states built civilization upon 18-20 century and now pursue very expensive "green" technologies. While India and others will hardly catch up just with those expensive new techs. They need coal etc for their unprecented expansion or get those techs for "free". Basically for me problem stands in "bad luck for some is opportunity for others" mentality. Plus it is very easy to talk about something but push something through our democracy system. Just for exmaple we in Czech republic need retirement pension reform but it is so unpopular and hard topic to crack that for 30 years after Velvet revolution no one party can crack it.

    Call me cynic but sooner of later there will be another massive conflict. I don´t want it or want to spread fear about it. Nope. But looking back at whole human history. Those climatic changes will bring major changes to parts of earth where live a few billions of people. Pair it with technology advancement and sooner or later..... We have enough examples from history, bronze age collapse and sea people - nice exmaple of trade collapse, slow fall of roman empire - that is particullary good example how multiple problems meet enviromental problems and other issues like even plague outbreaks ....

    What I try to say. Humanity in thery could still if not prevent catastrophe, at least lower impact. But that would require unified and global effort. And that is very unlikely to happen due to human nature.Just look how UK try to leave EU to pursue better conditions for itself, how USA under Trump try to get more from trade wars...I´m not saying they are bad or evil no no just that politicians try to think about next election. Definitely not about what will be after that...:/

    All the talks about natural cycles, ice ages,....It is sadly only cover to hide our true human nature. :/ Sadly.

    --
    Cool, looks like I´m not today such optimist. Despite being Scientist. Simply all the things you wrote for me are nicely to understand. Long term effects and links which should be easily taken into picture, some chaotic over which we cannot have control like volcanic activity. So in my eyes it should be very possible to alter earth just little. Because after all this is the best planet for human life. If we cannot alter this our planet on grand scale, just little...like 1% here, 2% there..how we want to terraform others? But problem lies with humanity. My favourite quote is that even communism would work with perfect people (any system would) but people are far from perfect hence why it never will work....and similar can be said about multiple areas of humanity sadly.

    So it boils down to simple question. Will shattered multi party humanity have enough willpower to do it? To counter or adapt at leas tto these conditions on grand scale?
    Last edited by Daruwind; January 12, 2020 at 07:28 AM.

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    Genava's Avatar Centenarius
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    Default Re: What is the reality of Climate Change?

    Good post Copperknickers II!

    Long-term trends in geoclimatology: this is a favourite of climate change denialists. The Milankovitch cycles, combined with tectonic shifts in the position of the continents (and corresponding paths of ocean currents) seem to be largely responsible for the phenomenon of 'Ice Ages', one of which we are currently in, specifically an interglacial period between two nadirs of glacial activity. The trajectory over the course of the next 25-50,000 years is towards a glacial maximum which would replicate conditions when most of modern North Europe and Canada were covered in thick ice sheets and mammoths roamed the tundra. However, this is in large part dependent on us having polar ice caps in place (due to the feedback loop created by the Albedo effect which means massive-scale glaciation reflecting the sun's energy) and atmospheric carbon levels remaining largely stable. As such,
    Another myth to bust is the idea that the actual warming is caused by the Milankovitch cycle. Actually the solar radiation reaching the Northern hemisphere is decreasing. Here you can see how the effect on solar radiation reaching the Arctic from three orbital parameters is modelled (in yellow):


    Moreover, people are generally confused with the Milankovitch cycle, thinking it is the SOLE explanation for the temperature during the glacial and interglacial periods. Actually it is wrong, it acts as a trigger only at specific moment when the differences in solar radiation reaching the Arctic is big enough to activate a long increase in greenhouse gases by ocean mixing and warming and to activate a long decrease in sea ice and ice sheet area. Both albedo and the greenhouse feedbacks are the main explanation of the rate of change in temperature. When the variation in solar radiation from orbital parameters is not big enough, the global temperature mostly ignores it.



    This leads to an easy lie spread by deniers that "CO2 only follows temp" therefore CO2 has not effect. This is a very unintelligent idea and a strawman argument. It ignores the position of the scientific community, which says CO2 is a necessary feedback to explain the rate of changes in temperature. Moreover, the CO2 was mostly preceding the temperature during the end of the last glacial period.

    The role of orbital parameters are simply summarized here by Richard Alley at the National Academy of Sciences annual meeting (at 18m00 he starts talking about the recent ice ages):



    Manmade C02 emissions This needs no further explanation, I think! Unless anyone wants to seriously claim that C02 emissions don't have a track record of leading to climate change, or that we aren't reducing large quantities of greenhouse gases. If so, go ahead, I'm game.
    Oh you could be impressed with the level of bad faith on this topic. Easy lies like "CO2 is a trace gas" or "water vapor is the strongest greenhouse gas" are enough for the weak minds.

    It is really bothering that a very old topic is denied like this. It started a long time ago with Tyndall:
    https://rmets.onlinelibrary.wiley.co...0.1002/wea.386

    Then it was Svante Arrhenius in 1896: http://www.rsc.org/images/arrhenius1...m18-173546.pdf

    Thomas Chrowder Chamberlin, 1899: https://www.jstor.org/stable/30055497

    Guy Stewart Callendar, 1938: http://www.met.reading.ac.uk/~ed/callendar_1938.pdf

    Gilbert Norman Plass, 1956: https://www.americanscientist.org/ar...nd-the-climate

    Arrhenius and Chamberlin already understood the feedback operating between the non-condensing greenhouse gases like CO2 and the water vapor, a condensing greenhouse gas:


    Gilbert Norman Plass brilliantly summarized the primary role of CO2 on the climate:
    Quote Originally Posted by Gilbert Norman Plass
    In a similar manner the temperature at the surface of the Earth is controlled by the transparency of the atmosphere in the visible and infrared portions of the spectrum. The incoming radiation from the sun in the visible portion of the spectrum reaches the surface of the Earth on a clear day with relatively little attenuation since the atmosphere is transparent to most frequencies in the visible. However, in order to have a warm climate, this heat energy must be held near the surface of the Earth and cannot be reradiated to space immediately. The atmosphere is opaque or partially opaque to a large range of frequencies in the infrared because of the absorption properties of the three relatively rare gases described above. Thus radiation emitted by the Earth’s surface cannot escape freely to space and the temperature at the surface is higher than it would be otherwise. The atmosphere has just the same properties as the glass in the greenhouse. The carbon dioxide theory states that, as the amount of carbon dioxide increases, the atmosphere becomes opaque over a larger frequency interval; the outgoing radiation is trapped more effectively near the Earth’s surface and the temperature rises. The latest calculations show that if the carbon dioxide content of the atmosphere should double, the surface temperature would rise 3.6 degrees Celsius and if the amount should be cut in half, the surface temperature would fall 3.8 degrees.

    The carbon dioxide theory was first proposed in 1861 by Tyndall. The first extensive calculations were necessarily done by very approximate methods. There are thousands of spectral lines due to carbon dioxide which are responsible for the absorption and each of these lines occurs in a complicated pattern with variations in intensity and the width of the spectral lines. Further the pattern is not even the same at all heights in the atmosphere, since the width and intensity of the spectral lines varies with the temperature and pressure. Only recently has a reasonably accurate solution to the problem of the influence of carbon dioxide on surface temperature been possible, because of accurate infrared measurements, theoretical developments, and the availability of a high-speed electronic computer.

    The fact that water vapor absorbs to some extent in the same spectral interval as carbon dioxide is the basis for the usual objection to the carbon dioxide theory. According to this argument the water vapor absorption is so large that there would be virtually no change in the outgoing radiation if the carbon dioxide concentration should change. However, this conclusion was based on early, very approximate treatments of the very complex problem of the calculation of the infrared flux in the atmosphere. Recent and more accurate calculations that take into account the detailed structure of the spectra of these two gases show that they are relatively independent of one another in their influence on the infrared absorption. There are two main reasons for this result: (1) there is no correlation between the frequencies of the spectral lines for carbon dioxide and water vapor and so the lines do not often overlap because of nearly coincident positions for the spectral lines; (2) the fractional concentration of water vapor falls off very rapidly with height whereas carbon dioxide is nearly uniformly distributed. Because of this last fact, even if the water vapor absorption were larger than that of carbon dioxide in a certain spectral interval at the surface of the Earth, at only a short distance above the ground the carbon dioxide absorption would be considerably larger than that of the water vapor. Careful estimates show that the temperature changes given above for carbon dioxide would not be reduced by more than 20 per cent because of water vapor absorption.
    Those were the pioneers on the topic. This was the physical background that built the current view of the scientific community, emerging the following years among scientists. It was not the IPCC, created in 1988, that made the consensus on the matter.

    It was the report from the President’s Science Advisory Committee in 1965 (under Lyndon B. Johnson):http://www.climatefiles.com/climate-...arbon-dioxide/
    And it was the report in 1979 by the National Research Council: https://www.bnl.gov/envsci/schwartz/...report1979.pdf

    Even before the acceleration in the warming occurring from the 1980s, scientists were already expected to see an important global warming.

    The evidences for carbon dioxide were simply building up decade after decade and now there are so many evidences that it is one of the most solid theory:

    Spoiler Alert, click show to read: 

    Radiative forcing ‐ measured at Earth's surface ‐ corroborate the increasing greenhouse effect
    https://agupubs.onlinelibrary.wiley....9/2003GL018765

    Global atmospheric downward longwave radiation over land surface under all-sky conditions from 1973 to 2008
    https://agupubs.onlinelibrary.wiley....9/2009JD011800

    Infrared radiation and planetary temperature
    https://geosci.uchicago.edu/~rtp1/pa...odayRT2011.pdf

    Increases in greenhouse forcing inferred from the outgoing longwave radiation spectra of the Earth in 1970 and 1997
    https://www.researchgate.net/publica..._1970_and_1997

    On the causal structure between CO2 and global temperature
    https://www.nature.com/articles/srep21691
    https://phys.org/news/2016-02-eviden...an-global.html

    Observational determination of surface radiative forcing by CO2 from 2000 to 2010
    http://asl.umbc.edu/pub/chepplew/jou...eldman_CO2.pdf

    Dependence of global temperatures on atmospheric CO2 and solar irradiance
    https://www.researchgate.net/publica...lar_irradiance

    Global Warming and Global Dioxide Emission: An Empirical Study
    https://www.researchgate.net/publica...mpirical_Study

    Why natural cycles only play small role in rate of global warming
    https://www.carbonbrief.org/guest-po...global-warming

    A limited role for unforced internal variability in 20th century warming
    https://journals.ametsoc.org/doi/abs...18-0555.1?af=R

    Human and natural influences on the changing thermal structure of the atmosphere
    https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3808612/





    Especially this study by Feldman et al. (2015) called "Observational determination of surface radiative forcing by CO2 from 2000 to 2010". They were able to see the fluctuation of the CO2 concentration in the amosphere in their measurements. The seasonality of CO2 was in the infrared radiation measured! And they carefully took in account the wavelenghts to rule out any perturbation by water vapor or change in temperature. It was a flawless demonstration and the measurements confirmed the calculations made by previous physicists for climate modelling:
    https://phys.org/news/2015-02-carbon...se-effect.html


    Source: https://climatefeedback.org/claimrev...used-townhall/

    Finally, the way the warming is occurring is strongly suggesting that it is caused by increasing greenhouse gases.
    Night warming faster than days as predicted by Tyndall 170 years ago:
    https://phys.org/news/2016-03-nights...ster-days.html

    Stratospheric cooling because more radiant heat (infrared) got stuck in the troposphere by greenhouse gases:
    https://www.csmonitor.com/Environmen...sphere-cooling
    https://www.earth-syst-dynam.net/7/6...7-697-2016.pdf
    https://www.yaleclimateconnections.o...heric-warming/
    Last edited by Genava; January 15, 2020 at 04:02 PM.
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    Default Re: What is the reality of Climate Change?

    P-E thermal maximum is theorised to have increased temperatures by around 7 degrees. This is actually within the worst-case scenario estimates of manmade climate change...
    Don't believe this bull -the science behind all of this is HIGHLY questionable.

    If there were ever a massive volcanism event, we might see entirely natural global warming on a devastating scale. However this might not happen for millions of years and, while it should be of concern to the survival of the human race on planet earth in the long term, it's actually a threat of a magnitude not disimilar to what we may see in the very near future due to manmade action.
    LOL...Yeah cool story Bro!
    Last edited by Stario; January 21, 2020 at 08:21 AM.

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    Genava's Avatar Centenarius
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    Default Re: What is the reality of Climate Change?

    Don't believe this bull -the science behind all of this is HIGHLY questionable.
    The Palaeocene–Eocene Thermal Maximum as recorded in benthic foraminiferal isotopic records at different locations:


    Moreover, there are fossil records and sedimentary records suggesting it was much warmer:
    https://www.e-education.psu.edu/earth103/node/1039
    https://www.geol.umd.edu/~tholtz/G20...s/204PETM.html
    https://www.whoi.edu/fileserver.do?i...&pt=2&p=148709
    https://www.sciencedirect.com/scienc...69534706000930

    Since you are saying "the science behind all of this is HIGHLY questionable", please explains the records.
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    Default Re: What is the reality of Climate Change?

    Quote Originally Posted by Geneva
    Moreover, there are fossil records and sedimentary records suggesting it was much warmer
    So the Earth has cooled NOT warmed. I feel we are making some progress here...

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    Genava's Avatar Centenarius
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    Default Re: What is the reality of Climate Change?

    Quote Originally Posted by Stario View Post
    So the Earth has cooled NOT warmed. I feel we are making some progress here...
    Oh so you are actually admitting that the PETM was warmer with higher CO2 and that the Earth has cooled with lowering CO2 concentrations in the atmosphere.

    Sorry. I thought you were shooting pseudoscience claims. Actually, we are making progress here indeed.
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    Default Re: What is the reality of Climate Change?

    Quote Originally Posted by Genava View Post
    Good post Copperknickers II!



    Another myth to bust is the idea that the actual warming is caused by the Milankovitch cycle. Actually the solar radiation reaching the Northern hemisphere is decreasing. Here you can see how the effect on solar radiation reaching the Arctic from three orbital parameters is modelled (in yellow):


    Moreover, people are generally confused with the Milankovitch cycle, thinking it is the SOLE explanation for the temperature during the glacial and interglacial periods. Actually it is wrong, it acts as a trigger only at specific moment when the differences in solar radiation reaching the Arctic is big enough to activate a long increase in greenhouse gases by ocean mixing and warming and to activate a long decrease in sea ice and ice sheet area. Both albedo and the greenhouse feedbacks are the main explanation of the rate of change in temperature. When the variation in solar radiation from orbital parameters is not big enough, the global temperature mostly ignores it.



    This leads to an easy lie spread by deniers that "CO2 only follows temp" therefore CO2 has not effect. This is a very unintelligent idea and a strawman argument. It ignores the position of the scientific community, which says CO2 is a necessary feedback to explain the rate of changes in temperature. Moreover, the CO2 was mostly preceding the temperature during the end of the last glacial period.
    Your own graph undermines the Clinate Change argument. At the far right of the graph, we see a sharp drop in temperature despite a rising a rising CO2, which goes against what Climate Change says. Yes, eventually we see a sharp and dramatic turn around in temperature, so eventually temperature caught up with with CO2, but the rise started before the really sharp rise in CO2. From the lines at the far right of the graph, it acts as if CO2 had little effect on temperature, until a limit of around 280 ppm was reached, and lower than that CO2 levels were not driving trmperatures. . Do.any models predict such a dramatic trigger point in CO2 levels? The fact that CO2 levels lead and sometimes lag temperature suggest tha CO2 levels were being drivrn by a 3rd factor that also had effect on temperature. Given that CO2 seemed had litte.effect preventing the rapid drop in temperature, why should we assume.the equally dramaric rise.in temperature was due to CO2?




    Oh you could be impressed with the level of bad faith on this topic. Easy lies like "CO2 is a trace gas" or "water vapor is the strongest greenhouse gas" are enough for the weak minds.
    It is comments like yours, bigoted and insulting, that moves me back to the skeptic camp after I have convinced myself of the climate change. All the data and models depend on trusting the integrity of those who are presenting the data, and I have no faith in someone who calls anyone who diagrees with them liars and weak minded.

    If you truly want to convince people I suggest you change your tactics, since you can present all the data in the world, and people are not.going to pay.any attention to it after you call them liars and weak minded.


    Of course, not all.Climate Change proponets are like, but unfortunately many are, which is why there are so many skeptics. If Climate Changr proponents were not so insulting and condescending, they would have convinced many of the skeptics by now.

    Truth is that if Climate Change were being judged according to US civil trial standards, "the preponderance of the evidence", any jury would.judge in favor of Climate Change, the preponderance of the evidence clearly supports Climate Change. Unless you were presenting the case for Climate Change, then the jury would find for the skeptics.
    Last edited by Common Soldier; January 23, 2020 at 12:42 AM.

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    Default Re: What is the reality of Climate Change?

    Quote Originally Posted by Common Soldier
    Your own graph undermines the Clinate Change argument. At the far right of the graph, we see a sharp drop in temperature despite a rising a rising CO2, which goes against what Climate Change says. Yes, eventually we see a sharp and dramatic turn around in temperature, so eventually temperature caught up with with CO2, but the rise started before the really sharp rise in CO2. From the lines at the far right of the graph, it acts as if CO2 had little effect on temperature, until a limit of around 280 ppm was reached, and lower than that CO2 levels were not driving trmperatures. . Do.any models predict such a dramatic trigger point in CO2 levels? The fact that CO2 levels lead and sometimes lag temperature suggest tha CO2 levels were being drivrn by a 3rd factor that also had effect on temperature. Given that CO2 seemed had litte.effect preventing the rapid drop in temperature, why should we assume.the equally dramaric rise.in temperature was due to CO2?
    You should read carefully the figure. There is an increase of 20 ppm during the Holocene while solar insolation in the Arctic is decreasing by about 20 W/m2 during Summer solstice. The increase of 20 ppm means globally only +0.2W/m2 in direct forcing and +0.4W/m2 approximately with the water vapor feedback. The same figure but centered on the Holocene:


    The drop in insolation had a huge effect on the Arctic region, probably increasing the sea ice (therefore the albedo). The late Holocene is also known the neoglaciation for the advance in glaciers worldwide.
    https://en.wikipedia.org/wiki/Neoglaciation

    And please, stop saying what is the "climate change argument" when you don't have any clues about what the science says on this topic. You are doing a strawman argument here.

    Obviously, there are three things that matter the most for the energy balance of the Earth:
    - Solar insolation
    - Albedo
    - Greenhouse gases

    Obviously, the increase of 20 ppm during the several millenia of the Late Holocene was not enough to compensate the more important changes in albedo. And no the CO2 didn't change its physical properties like you suggested. Between 1850 to 1950, the CO2 increases of about 25 ppm. Between 1950 and 2000, the CO2 increases of about 60 ppm. Between 2000 and 2018, the CO2 increases of about 40 ppm.

    I am specifically saying in my first message that the temperature during the glacial and interglacial periods depends on different feedbacks. CO2 is not the sole explanation, albedo is not the sole explanation and Milankovitch cycle is not the sole explanation. The three altogether are needed to explain most of the processes. And even here, I am simplifying the reality.

    The current warming is really special in regard to the past glacial periods because it is related to a unique forcing: CO2 increasing in a few decades at the same amplitude as it occurred during glacial termination over millenia. Albedo feedback is not playing an immense role for the moment and changes in solar irradiance are clearly not matching the temperature changes.

    And we have satellites and ground observation confirming the increasing greenhouse effect from a spectroscopic perspective.

    It is comments like yours, bigoted and insulting, that moves me back to the skeptic camp after I have convinced myself of the climate change. All the data and models depend on trusting the integrity of those who are presenting the data, and I have no faith in someone who calls anyone who diagrees with them liars and weak minded.
    For my part, it is:
    Your comments about the reliability of scientists, suggesting either they are dishonest or incompetent.
    Your double standard, being very critical of anything I give but accepting several BS from blog posts without any demonstration.
    Your egocentric nature, thinking you can contradict physical laws based on simplistic analogies and thinking you can approach science the same way you approach history.
    Your tendency to ignore the critical arguments in my messages.
    Your tendency to be inconsistent between your different arguments but with a continuous use of them individually to reject the consensus.

    These five things convinced me that I was not going to convince you. You displayed several of them early on.

    Of course, not all.Climate Change proponets are like, but unfortunately many are, which is why there are so many skeptics. If Climate Changr proponents were not so insulting and condescending, they would have convinced many of the skeptics by now.
    Yeah sure and antivaxxers are because of the pedantry of the immunologists. Climate denialism like other anti-scientific movements motivated by lobbying and political ideologies targets specifically the thrust for the scientific community. To convince someone that have accepted the arguments of the undermining campaign from deniers, you should work 10 times harder than the deniers. Anything said is twisted and overly misinterpreted with bad faith while the other side arguments are swallowed like candies.

    And this is the core of my issue with climate deniers:
    You are so motivated to contradict climate "proponents" that you are blind to the HUGE pile of lies and manipulations fabricated by the deniers. This is the worst double standard.

    This is why we don't have the feeling to deal with honest people but with zealots.


    Moreover, you don't have to deal personally with climate scientists to have a basic idea of the arguments and of the evidences. You just have to open a book or to read a report from an institution made to synthesis the scientific literature.
    https://www.ipcc.ch/site/assets/uplo...1-chapter1.pdf
    https://www.amazon.com/Discovery-Glo.../dp/067403189X
    https://www.wiley.com/en-us/The+Warm...-9781405196161
    https://www.springer.com/gp/book/9789400757561

    Problem: Nobody does it!
    Last edited by Genava; January 23, 2020 at 06:56 AM.
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  10. #10
    Stario's Avatar Campidoctor
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    Default Re: What is the reality of Climate Change?

    Oh so you are actually admitting that the PETM was warmer with higher CO2 and that the Earth has cooled with lowering CO2 concentrations in the atmosphere.

    Sorry. I thought you were shooting pseudoscience claims. Actually, we are making progress here indeed.
    Actually its quite the opposite- look at your own graph- temperature plummets despite rising C02.
    Interestingly- when the solar energy started to rise so did the temp; then as solar energy started to plummet so did the temperature followed by C02.
    This tells me C02 is NOT the primary driver of global warming/cooling.
    TA come again.
    Last edited by Stario; January 23, 2020 at 08:17 AM.

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    Default Re: What is the reality of Climate Change?

    ITT science vs "meh, don't like your tone".
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    Default Re: What is the reality of Climate Change?

    "This is what the number's say"

    "BUT MY FEEEEEEEELINGS"

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  13. #13

    Default Re: What is the reality of Climate Change?

    Quote Originally Posted by Genava View Post
    You should read carefully the figure. There is an increase of 20 ppm during the Holocene while solar insolation in the Arctic is decreasing by about 20 W/m2 during Summer solstice. The increase of 20 ppm means globally only +0.2W/m2 in direct forcing and +0.4W/m2 approximately with the water vapor feedback. The same figure but centered on the Holocene:


    The drop in insolation had a huge effect on the Arctic region, probably increasing the sea ice (therefore the albedo). The late Holocene is also known the neoglaciation for the advance in glaciers worldwide.
    https://en.wikipedia.org/wiki/Neoglaciation
    The Holocene started around 11,000 years ago, and that argument doesn't explain the sudden drop in temperature around what would be 1600 - 1800 CE on the graph. I said the "far right side of the graph", not the middle of the graph, which is what you are referring to. We can see a dramatic drop in temperature not correlated with drop in CO2. Being insulting doesn't change that fact. In fact, what the graph clearly shows is a drop in CO2 following the temperature drop, indicating that CO2 was following temperature, and not the reverse.

    And if you look very close at the graph, the temperature started to rise even more sharply than it fell BEFORE the CO2 started to rise - the last dip in CO2 levels occurred while temperatures were rising, severely undermining the climate change argument. More over, the human population in the 1700's didn't dramatically stop producing CO2 and while I am sure you can think up some clever lies, there is nothing in the historically record of human populations to support a decline in CO2 production we see around 11700 - 1800? that we see in the graph, just before the sharp rise in temperature the current era is experiencing.

    Also, what is apparent is the clear change in metrics used to determine temperature. The transition from a smooth temperature curve to the spiky one shown at the far right (far right, not middle of the grapsh). Because the graph isn't marked in a finer scale than every 2000 years, (even though it easily could have been), it is hard to tell exactly when that transition period occurred, but it seems to be around 1000 CE, probably when the oldest tree ring data became available. Whenever you change how you measure something can introduce errors, and for comparison with the past you should be using the same metric to give an honest and fair comparison. The change in metrics could introduced the errors, the world's temperature didn't miraculously become 10 time more erratic in the last 1000 years than in the previous 10,000. The last part of the graph (starting around 1000 CE?) should have been marked in a different color to alert people that there was a change in the way the temperatures were determined. A fair and honest person would make clear the change in metrics.

    For an accurate comparison with past temperatures, the same methods used to determine temperatures in the past should have been continued to modern times. I suspect that wasn't done, because the previous methods of determining temperature clearly had the effect of leveling out the changes in temperature, and so would not have given the dramatic temperature rise of the "hockey stick", which is why they prefer to switch metrics. As I have said, and any honest scientist (which is clearly not you) would admit, changing metrics makes accurate comparisons with the past using a different method of determining temperature very difficult.

    And please, stop saying what is the "climate change argument" when you don't have any clues about what the science says on this topic. You are doing a strawman argument here.
    Being insulting doesn't make you right. Since you can't bother to be polite, neither will I. Pounding the table and insisting the science is settled doesn't make it any more so. You can wave you hands all around you want, but your own graph demonstrates there are problems with your argument.


    Obviously, there are three things that matter the most for the energy balance of the Earth:
    - Solar insolation
    - Albedo
    - Greenhouse gases

    Obviously, the increase of 20 ppm during the several millenia of the Late Holocene was not enough to compensate the more important changes in albedo. And no the CO2 didn't change its physical properties like you suggested. Between 1850 to 1950, the CO2 increases of about 25 ppm. Between 1950 and 2000, the CO2 increases of about 60 ppm. Between 2000 and 2018, the CO2 increases of about 40 ppm.
    Are you just being dense? The issue is, that your own graph shows, a sharp drop in temperature while the CO2 was actually climbing, around 1700, 1800 CE. And there was a sharp dip in CO2 in around 1850? just as temperature was already starting to rise, according your own graph. Since we know that CO2 can follow temperature, as a honest scientist would admit, the dramatic rise in CO2 might just be a consequence rather than a cause of the rising temperature. As your own graph shows, we had a sharp drop in CO2 that came after a sharp fall in temperature, despite the fact that human CO2 production was almost certainly rising or at least steady. Yes, humans may be producing the majority of the CO2 rise seen, but it could be that with colder temperatures, more of the CO2 would simply haven been taken out of the atmosphere. That seems to be what we find during the drop in the little Ice Age, where after a continued rise in CO2 while temperature dropped, the CO2 level also eventually dropped following the temperature.

    I am specifically saying in my first message that the temperature during the glacial and interglacial periods depends on different feedbacks. CO2 is not the sole explanation, albedo is not the sole explanation and Milankovitch cycle is not the sole explanation. The three altogether are needed to explain most of the processes. And even here, I am simplifying the reality.
    Your graph deals with time only since the last glacial period, and so your comments above are totally irrelevant We see a drop in CO2 occurring after a drop in temperature around the time of the Little Ice Age that clearly follows, not proceeds, the drop in temperature, which argues against the CO2 being the driving factor of temperature change.

    And a very close look at the graph shows that temperature started rising just before the rise in CO2 and the end of the Little Ice Age, say around 1850 or so. As I said there is nothing in history to suggest a sharp drop in human CO2 production or even natural CO2 production to correspond to the dip in CO2 seen in the graph, but a sharp drop in temperature would allow greater uptake of CO2 in water, thus the drop in temperature would explain the drop in CO2. As temperatures rose, there would be less ability of the water to absorb the CO2, and so the human CO2 would cause the rising CO2 levels seen. But it was not CO2 driving the temperature, but rather temperature driving the CO2 levels, at least at first.

    The current warming is really special in regard to the past glacial periods because it is related to a unique forcing: CO2 increasing in a few decades at the same amplitude as it occurred during glacial termination over millenia. Albedo feedback is not playing an immense role for the moment and changes in solar irradiance are clearly not matching the temperature changes.
    Well your graph has solar incidence fall off the chart around 1 CE, so it is impossible to say what impact solar insolation is having, at least from your graph. I would have been nice if the solar insolation graph didn't end at 1 CE, when we are discussing what is happening around 1850 CE.



    For my part, it is:
    Your comments about the reliability of scientists, suggesting either they are dishonest or incompetent.
    What I suggest is the possibility that many, majority of the scientist could be suffering from tunnel vision, that they are so fixated on what they already think is the cause they are possibly misinterpreting the data, an unlikely scenario I agree, but something that is within the realm of possibility - people do win the lottery, even though the probability of that happening is low. Given the statistical and complex nature of complex nature of climate change data, and its highly politically charged nature, it could be prone to such "tunnel vision" than some other fields.

    And scientist, being human, some are probably dishonest or incompetent. Given how politicized Climate Change is, I do think that some scientist wouldn't be above fudging some of their data. It happens in other fields of science, where the data has been forged, and to claim climatologist are somehow exempt from common human faults is not a realistic claim. However, even if there was fraud by a few scientist, which has not been proven, I agree it would be an insignificant factor, and the results of the overwhelming majority of climatologist.

    You should take a leaf from the late Stephen Gould. Even though he clearly thought the creationist were completely wrong, unlike you, he never insulted the creationist or treated them with anything other than respect as he patiently explained why they were wrong, quite unlike you who insult those who don't agree with you in practically everything line you write.

    Your double standard, being very critical of anything I give but accepting several BS from blog posts without any demonstration.
    Your egocentric nature, thinking you can contradict physical laws based on simplistic analogies and thinking you can approach science the same way you approach history.
    Your tendency to ignore the critical arguments in my messages.
    Your tendency to be inconsistent between your different arguments but with a continuous use of them individually to reject the consensus.
    The above, when you engage in personal ad hominem attacks undermines your arguments. You clearly are more interested in insisting you are right that in convincing people the error of their ways.


    These five things convinced me that I was not going to convince you. You displayed several of them early on.
    Your attitude is what would never convince me. I have no respect or trust in anyone like you who calls their opponents liars or simple minded. As I said, I usually come convinced of Climate Change until I see what you wrote. Fortunately, most scientist are not like you. Unfortunately, many Climate Change supporters are just like you, which is why the debate is still raging.

    I agrue the point because many of my friends are skeptics, and I present the arguments I have heard from them to you. A lot of Americans are skeptics, and after listening to your rants and insults, they would be just more skeptical.

    You miss the point, is that all the scientific data and arguments in the world won't mean anything if people don't trust those presenting the data and arguments. If you call them weak minded, they will reject what you have to say, and you are just wasting you time. It is Climate Change supporters such as yourself that undermine the Climate Change cause. A real scientist, like Stephen Gould, can respectfully disagree with those he knows are wrong, you had only to read his old articles on evolution in the Nature magazine.


    Yeah sure and antivaxxers are because of the pedantry of the immunologists. Climate denialism like other anti-scientific movements motivated by lobbying and political ideologies targets specifically the thrust for the scientific community.
    Such are the words of a true bigot. I happen to know many climate change skeptics (and many climate change proponents as well), and they are not against vaccines, nor or they motivated by anti-science movements nor are they stooges for the oil companies. Yes, there are no doubt many anti-vaccine persons in the skeptic camps, but some of the anti-vaccine persons also happen to be in the Climate Change camp as well. You clearly don't know have any skeptics who are friends or know any personally, which says about your intolerant nature. A bigot judges people they don't know on preconceived ideas, and that is you.

    Just as the "social justice" and "anti-nuclear" political stance of many Climate Change supporters don't effect the science supporting, neither should the existence of anti-vaccines and gun riights advocate in the skeptic camps should completely discredit all skeptics.

    To convince someone that have accepted the arguments of the undermining campaign from deniers, you should work 10 times harder than the deniers. Anything said is twisted and overly misinterpreted with bad faith while the other side arguments are swallowed like candies.

    And this is the core of my issue with climate deniers:
    You are so motivated to contradict climate "proponents" that you are blind to the HUGE pile of lies and manipulations fabricated by the deniers. This is the worst double standard.

    This is why we don't have the feeling to deal with honest people but with zealots.
    I genuflect the awesomeness of your superior knowledge. Why bother posting all those links if you are not interesting in persuading others because they are all "zealots"? You could save a lot of time if you just asserted "I am right, you are wrong and anyone who disagrees with me is a moron!" No skeptic is going to waste their time reading any of your links after you are done insulting them as you do.

    if your goal is to make skeptics even more skeptical, you are doing a good job. If your goal is actually persuade skeptics they are wrong, your methods could use some improvement. if you believe skeptics are all zealots who will be deniars no matter what, then why are you wasting your time? .

    Moreover, you don't have to deal personally with climate scientists to have a basic idea of the arguments and of the evidences. You just have to open a book or to read a report from an institution made to synthesis the scientific literature.
    https://www.ipcc.ch/site/assets/uplo...1-chapter1.pdf
    https://www.amazon.com/Discovery-Glo.../dp/067403189X
    https://www.wiley.com/en-us/The+Warm...-9781405196161
    https://www.springer.com/gp/book/9789400757561

    Problem: Nobody does it!
    And nobody will read all those reports you listed when they come from someone who insist they are all liars. They are jus tall going to ignore all your links, and will continue to do so when you keep calling them weak minded, and liars as you have done.

    As I said, I think any reasonable person if they were on a jury, and presented all the evidence, would find in favor of Climate Change, the preponderance of the evidence overwhelmingly supports climate change. But a Climate Change proponent starts making claims that skeptics are all against vaccines, anti-science, and liars, that same jury will likely find against Climate Change, because that is the nature of the people.
    Last edited by Lifthrasir; January 24, 2020 at 07:57 AM. Reason: Personal Reference part removed

  14. #14
    Genava's Avatar Centenarius
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    Default Re: What is the reality of Climate Change?

    Quote Originally Posted by Common Soldier
    Your attitude is what would never convince me. I have no respect or trust in anyone like you who calls their opponents liars or simple minded. As I said, I usually come convinced of Climate Change until I see what you wrote. Fortunately, most scientist are not like you. Unfortunately, many Climate Change supporters are just like you, which is why the debate is still raging.
    I am ready to make an effort to find a healthy conversation. I apologize for my attitude and I apologize for putting you in the same category as B.W. and Stario. I may have misinterpreted your intentions.

    Quote Originally Posted by Common Soldier
    What I suggest is the possibility that many, majority of the scientist could be suffering from tunnel vision, that they are so fixated on what they already think is the cause they are possibly misinterpreting the data, an unlikely scenario I agree, but something that is within the realm of possibility - people do win the lottery, even though the probability of that happening is low. Given the statistical and complex nature of complex nature of climate change data, and its highly politically charged nature, it could be prone to such "tunnel vision" than some other fields.

    And scientist, being human, some are probably dishonest or incompetent. Given how politicized Climate Change is, I do think that some scientist wouldn't be above fudging some of their data. It happens in other fields of science, where the data has been forged, and to claim climatologist are somehow exempt from common human faults is not a realistic claim. However, even if there was fraud by a few scientists, which has not been proven, I agree it would be an insignificant factor, and the results of the overwhelming majority of climatologist.
    Your message sounds legit and less polemical than the previous ones. If this is your concerns, I don't have any issues to discuss and to tell you why I don't think it is the case. However, I really want you to remember that you were far more provocative in the past:
    Quote Originally Posted by Common Soldier View Post
    All the evidence in the world if people don't trust the those presenting the data. There are a number of ways that scientist could adjust the results to get their
    And that's your whole comment about my message where I was replying to B.W. : "Different groups from different countries and different institutions, using different methodology on different data, all found a Hockey Stick trend. But they are "manipulated". How comfortable it is to be blind...", I even gave the evidences a few messages before, on the same page of the thread.

    Understand that for me, suspecting the scientific community is a sign that gives me a very bad image of my interlocutor. I know there are bad scientists, I know that lobbying exists as it did with tobacco, but to generalize at this point it bothers me a lot. The scientific community is not a true community in the strict sense, scientists come from different scientific fields, different countries, different religions, different cultures, speak different languages etc. The question of the role of CO2 in the climate is an old one and most people think it is a topic ONLY for climate scientists and an issue rose by climate scientists but it is totally not the case. The question interested mostly physicists at a time when the topic was absolutely NOT a political issue. Now, there is what we call a "consensus" which is simply a general agreement among the different scientific fields and in the scientific literature where the core of the scientific theory about the role of CO2 in the climate is not contested by anyone, except by a minority of people whose arguments suffer from several biases and whose fallacious approach and links of interest raise concerns. For example the fact that most contrarians have links with the Heartland Institute, which is a known anti-science think tank notably on the question of tobacco. Or the fact that most contrarians are not arguing against the scientific theory and against the evidences but to a strawman they built themselves.

    The probability that most of the studies about climate and CO2 for the last 70 years are flawed by ideologies, tunnel vision or confirmation biais is very low in my opinion.

    And for the approximately 10 years of experience I have in debating the question of vaccination or climate change, I have never been able to convince someone with strong griefs against the scientific community. I did have some successes with a few persons, even some elected politicians in Switzerland, but they were mostly favorable to science. Sometimes it was a bit hard to correct the lies on the IPCC and how it works but that's all.

    But maybe you have misspoke your opinion and maybe I have over-interpreted your message. If this is the case, I apologize for my part.

    Quote Originally Posted by Common Soldier
    Being insulting doesn't make you right. Since you can't bother to be polite, neither will I. Pounding the table and insisting the science is settled doesn't make it any more so. You can wave you hands all around you want, but your own graph demonstrates there are problems with your argument.
    Could you point it out where I say that the science is settled? It is a running cliché, this sentence is more often attributed to scientists than they are actually expressing it.
    https://www.csiro.au/en/Research/Oan...nge-QA/Science

    And again, I don't think you are understanding my argument. I never said that any tiny changes in CO2 will always cause significant temperature changes.

    Quote Originally Posted by Common Soldier
    Well your graph has solar incidence fall off the chart around 1 CE, so it is impossible to say what impact solar insolation is having, at least from your graph. I would have been nice if the solar insolation graph didn't end at 1 CE, when we are discussing what is happening around 1850 CE.
    What about the two other figures previously posted?

    Quote Originally Posted by Common Soldier
    You clearly don't know have any skeptics who are friends or know any personally, which says about your intolerant nature. A bigot judges people they don't know on preconceived ideas, and that is you.
    Actually, I have several members of my family that are strong antivaxxers activists.

    I didn't say that climate deniers are antivaxxers. I simply highlighted the analogy. Antivaxxers are not because of the way immunologists and society talk to them about the issue => analogy to your opinion that skeptics are because of the way society talks about the issue. If it was the case, the climate denial wouldn't be that much politically centered on libertarian and conservative supporters.

    Quote Originally Posted by Common Soldier
    The Holocene started around 11,000 years ago, and that argument doesn't explain the sudden drop in temperature around what would be 1600 - 1800 CE on the graph. I said the "far right side of the graph", not the middle of the graph, which is what you are referring to. We can see a dramatic drop in temperature not correlated with drop in CO2. Being insulting doesn't change that fact. In fact, what the graph clearly shows is a drop in CO2 following the temperature drop, indicating that CO2 was following temperature, and not the reverse.
    Well honestly, both were on the far right of the figure. I thought you were talking about the Holocene cooling trend. I will answer your message about the Little Ice Age but later. Today I am busy.
    Last edited by Lifthrasir; January 24, 2020 at 07:59 AM. Reason: For continuity
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    Default Re: What is the reality of Climate Change?






  16. #16
    Genava's Avatar Centenarius
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    Default Re: What is the reality of Climate Change?

    Quote Originally Posted by Common Soldier
    Your graph deals with time only since the last glacial period, and so your comments above are totally irrelevant We see a drop in CO2 occurring after a drop in temperature around the time of the Little Ice Age that clearly follows, not proceeds, the drop in temperature, which argues against the CO2 being the driving factor of temperature change.
    So here the greenhouse gases concentrations from the Antarctic ice cores (up to 2005):


    And here a climate model for a few forcing drivers during the past:

    http://web-static-aws.seas.harvard.e...et_al_2006.pdf

    I don't see how it contradicts the fact that CO2 has an effect on the climate.

    Edit: If you are more interested on the matter

    Northern Hemisphere summer temperatures over the past 8000 years have been paced by the slow decrease in summer insolation resulting from the precession of the equinoxes. However, the causes of superposed century‐scale cold summer anomalies, of which the Little Ice Age (LIA) is the most extreme, remain debated, largely because the natural forcings are either weak or, in the case of volcanism, short lived. Here we present precisely dated records of ice‐cap growth from Arctic Canada and Iceland showing that LIA summer cold and ice growth began abruptly between 1275 and 1300 AD, followed by a substantial intensification 1430–1455 AD. Intervals of sudden ice growth coincide with two of the most volcanically perturbed half centuries of the past millennium. A transient climate model simulation shows that explosive volcanism produces abrupt summer cooling at these times, and that cold summers can be maintained by sea‐ice/ocean feedbacks long after volcanic aerosols are removed. Our results suggest that the onset of the LIA can be linked to an unusual 50‐year‐long episode with four large sulfur‐rich explosive eruptions, each with global sulfate loading >60 Tg. The persistence of cold summers is best explained by consequent sea‐ice/ocean feedbacks during a hemispheric summer insolation minimum; large changes in solar irradiance are not required.

    https://agupubs.onlinelibrary.wiley....9/2011GL050168



    Edit2:
    Quote Originally Posted by Common Soldier
    For an accurate comparison with past temperatures, the same methods used to determine temperatures in the past should have been continued to modern times. I suspect that wasn't done, because the previous methods of determining temperature clearly had the effect of leveling out the changes in temperature, and so would not have given the dramatic temperature rise of the "hockey stick", which is why they prefer to switch metrics.
    So here the result with the same proxy up to 1960:
    Last edited by Genava; February 03, 2020 at 06:39 PM.
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