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    From Wikepedia - but show me something that doesn't have warming and cooling. To only have cooling seems scientifically oxymoronic. https://en.wikipedia.org/wiki/8.2_kiloyear_event#/media/File:Greenland_Gisp2_Temperature.svg

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    Alan Cannell, <blockquote>... these forests (covering an area about the size of Brazil) were drowned and the carbon stored presumably lost into the atmosphere in a very short period.</blockquote> What mass of carbon do you estimate was released from submergence of these forests, what proportion went to the atmosphere and what went into the oceans, and over what time period? I Understand it took around 10,000 years for sea level to rise from LGM.

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    . ❶①❶①❶①❶①❶①❶①❶①❶①❶①❶①❶ ❶①❶① ❶①❶① . . . A global warming paradox . . . ❶①❶① ❶①❶①❶①❶①❶①❶①❶①❶①❶①❶①❶ . Imagine that you have a "big" date range, which has a warming rate of "B" degrees Celsius per century. You decide to split the big date range at a year somewhere near the middle of the big date range, to give 2 smaller date ranges. It important to realise, that joining the 2 smaller date ranges together, produces the original big date range. There is no overlap between the 2 smaller date ranges, and there is no gap between the 2 smaller date ranges. One smaller date range stops, where the other smaller date range starts. The 2 smaller date ranges have warming rates of "S1" and "S2". What is the relationship between "B" (the warming rate of the big date range), and "S1" and "S2" (the warming rates of the 2 smaller date ranges). Do "S1" and "S2" have to be near "B"? Does "B" have to be near to the average of "S1" and "S2"? ==================== Have a look at these 2 graphs: http://woodfortrees.org/plot/uah6/trend/plot/uah6/from:1978/to:1998/trend/plot/uah6/from:1998/to:2019/trend/plot/uah6/mean:12 http://woodfortrees.org/plot/uah6/trend/plot/uah6/from:1978/to:1999/trend/plot/uah6/from:1999/to:2019/trend/plot/uah6/mean:12 Can you explain what is happening in these 2 graphs? This example uses UAH global lower troposphere temperature anomalies. The big date range is 1980 to 2018. In the first graph, the 2 smaller date ranges are 1980 to 1998, and 1998 to 2018. Both of the smaller date ranges, have warming rates which are considerably lower than the warming rate of the big date range. In the second graph, the 2 smaller date ranges are 1980 to 1999, and 1999 to 2018. Both of the smaller date ranges, have warming rates which are higher than the warming rate of the big date range. How can this be? There is only 1 year difference, in where the big date range was split. But the warming rates of the 2 smaller date ranges, do opposite things in the 2 graphs. ==================== Try to work out the reason, for these apparently contradictory results. If you want some help, or you want to check your answer, then read this article: https://agree-to-disagree.com/split-date-ranges

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    From the link under the graph - that you said you had seen. "The covariation of carbon dioxide (CO2) concentration and temperature in Antarctic ice-core records suggests a close link between CO2 and climate during the Pleistocene ice ages. The role and relative importance of CO2 in producing these climate changes remains unclear, however, in part because the ice-core deuterium record reflects local rather than global temperature. Here we construct a record of global surface temperature from 80 proxy records and show that temperature is correlated with and generally lags CO2 during the last (that is, the most recent) deglaciation. Differences between the respective temperature changes of the Northern Hemisphere and Southern Hemisphere parallel variations in the strength of the Atlantic meridional overturning circulation recorded in marine sediments. These observations, together with transient global climate model simulations, support the conclusion that an antiphased hemispheric temperature response to ocean circulation changes superimposed on globally in-phase warming driven by increasing CO2 concentrations is an explanation for much of the temperature change at the end of the most recent ice age." Or this? http://www.ajsonline.org/content/312/4/417.abstract So two out of three. Here's the other. https://www.sciencedirect.com/science/article/abs/pii/S0277379113004198 Yes - I'd suggest you focus on the emerging land - everything else seems irrelevant. But there your carbon cycle misses far too much to be interesting.

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    <blockquote>The Younger Dryas and the 8.2 KY event?</blockquote> YD was a cooling period outside the Holocene and within deglaciation warming. And 8.2-kyr ACE was a cooling event as even kids know. Zero examples so far. It shouldn't be so difficult to come up with known Holocene warming events, should it? Let's see… Preboreal oscillation? No, that was a cooling one. Boreal oscillations? No, those were cooling ones too. The 9.3-kyr event? No, a cooling one too. The 8.2-kyr event? Another cooling. The 5.2-kyr event? No, that's the cooling one that froze poor Ötzi. The 2.7-kyr event? Damm, another cooling one. Hey it's more difficult that it looks. I bet you thought there were as many warming events as cooling events. Yeah, that's what chaos would predict. Equal probabilities and all that stuff. But that is not how climate works.

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    Bargucada na mesa e uma coisa..... bargucada em pensamentos e outra.

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    sorry, baguncada, not bargunsada

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    You are being quite odd. The Holocene optimum, the Minoan warm period, the Medieval warm period and the modern max? Abrupt climate change - warming and cooling. http://www.use-due-diligence-on-climate.org/wp-content/uploads/2016/11/Historical-Temperatures-3.jpg "What defines a climate change as abrupt? Technically, an abrupt climate change occurs when the climate system is forced to cross some threshold, triggering a transition to a new state at a rate determined by the climate system itself and faster than the cause. Chaotic processes in the climate system may allow the cause of such an abrupt climate change to be undetectably small." NAS 2002 A chapter of this was linked above because it is still a great starting point. If you read more widely before jumping to conclusions it wouldn't be hypothetical enthusiasms I suppose.

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    And you are confusing random change with deterministic chaos.

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    The cooling into the YD actually took awhile. The warming out of YD was, well, there's a word for it. Trying to think of it. Oh yeah, abrupt. It was abrupt.

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    https://www.deviantart.com/atlas-v7x/art/Coastlines-of-the-Ice-Age-685023258

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    It all takes a while y'all. But if all you do is play with words or examine the graphical entrails - and don't understand the fundamental Earth system mode of operation... "Since irradiance variations are apparently minimal, changes in the Earth’s climate that seem to be associated with changes in the level of solar activity—the Maunder Minimum and the Little Ice age for example—would then seem to be due to terrestrial responses to more subtle changes in the Sun’s spectrum of radiative output. This leads naturally to a linkage with terrestrial reflectance, the second component of the net sunlight, as the carrier of the terrestrial amplification of the Sun’s varying output." http://bbso.njit.edu/Research/EarthShine/literature/Goode_Palle_2007_JASTP.pdf With Milankovitch - it is AMOC, runaway ice sheet and no doubt other feedbacks. At other times it is cloud, dust, rainfall, vegetation and sea ice responding to chaotic shifts over decades to millennia in ocean and atmospheric circulation and modulating the global energy budget. "The climate system has jumped from one mode of operation to another in the past. We are trying to understand how the earth's climate system is engineered, so we can understand what it takes to trigger mode switches. Until we do, we cannot make good predictions about future climate change... Over the last several hundred thousand years, climate change has come mainly in discrete jumps that appear to be related to changes in the mode of thermohaline circulation." Wally Broecker The US National Academy of Sciences (NAS) defined abrupt climate change as a new climate paradigm as long ago as 2002. A paradigm in the scientific sense is a theory that explains observations. A new science paradigm is one that better explains data – in this case climate data – than the old theory. The new theory says that climate change occurs as discrete jumps in the system. Climate is more like a kaleidoscope – shake it up and a new pattern emerges – than a control knob with a linear gain.

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    <blockquote>Abrupt climate change – warming and cooling.</blockquote> Not in the Holocene. In the Holocene it is cooling and warming. The warming comes after the cooling as recovery. <blockquote>The Holocene optimum, the Minoan warm period, the Medieval warm period</blockquote> You have no idea what I am talking about, have you? Those are not events. They are periods. And each one cooler than the previous so they came after more cooling than warming.

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    Ahh, again going the wrong way. We are talking global or hemispheric multi-centennial events, not Central Greenland temperature. GISP2 is not a good record of Holocene variability.

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    <blockquote>Since irradiance variations are apparently minimal, changes in the Earth’s climate that seem to be associated with changes in the level of solar activity</blockquote> This hides the assumption that solar variability effect on climate acts through changes in TSI. Assumptions are a dangerous thing, as they are invisible but can make it impossible for you to get to the correct answer. <blockquote>Climate is more like a kaleidoscope – shake it up and a new pattern emerges –</blockquote> These are the type of unsupported positions that make it impossible for you to understand what is going on with climate. The NAS has the same problem as the IPCC, they took a position before there was sufficient evidence to support it, and since they are trying to defend it with a strong bias towards evidence.

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    Krugman, who was once a brilliant economist who made a major theoretic contribution, notably on international trade, long ago lost credibility with serious economists. He wrote a book to explain economics simply to the non-cognescenti; that was fine, but it led to his columns in the NYT and swallowing the Green-Left Kool-aid. Best to ignore him.

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    […] From CE’s About page: […]

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    https://www.skepticalscience.com/4-Hiroshima-bombs-worth-of-heat-per-second.html And Dana Nuccitelli comments on a new story at the Guardian about atomic bombs. Is it 1 or 1.5 or 4 per second? You're fired. Let me see if I have this right. 90% into the oceans. Might be 1 times X or 4 times X. Our 90% is from 1X to 4X. You're fired and I am suing you. Odds on the Guardian quoting Dana Nuccitelli on any climate story? Over 50%. Now, our 1X to 4X, thank you Guardian, is close to from 1.5 C to 4.5 with 66% certainty. So our 30 some years of research failing to narrow the ECS, translates as it must, to the ocean heat content. Or to say it like an accountant, the OHC allows us to back into the ECS. If we knew what was going with the OHC, which am not so sure about. Now, is the coral going to die? We don't know. Antarctica? Coin flip. Please donate to the Guardian, as I need something to entertain myself and I don't want them to go out of business just yet.

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    its funny how CERTAIN ya'll are about time periods in which there is no actual data, or precious little to speak of.

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    Steve and Franktoo [IN FACT ALL READERS AS THIS IS AN IMPORTANT POINT THAT THE GUYS HAVE RAISED} The question of patm at new sea levels is one which has been a bit confused since the original work by Mélières et al 1991, in which she shows (by using overal air mass) that sea-level pressure was pretty much the same in the LGM - without making it clear which sea level was being mentioned (mslP) present or msl LGM. Using the fluid analogy you get that patm at mslP does not change - I got stuck on this as well. Thinking in terms of gas, in which the large volume of ice is very small in relation to the overall volume, you get that patmLGM (the bottom of the air 'column' is pretty much the same as patm mslP. So before reaching for the digital ink, let's see what the pros do. A quick check showed that climate models of the LGM that take into account exposed lands and ice use patm at mslLGM as the same as present values: S.-J. Kim G.M. Flato G.J. Boer A coupled climate model simulation of the Last Glacial Maximum, Part 2: approach to equilibrium Climate Dynamics (2003) 20: 635–661 DOI 10.1007/s00382-002-0292-2 The LGM surface climate and atmospheric circulation over East Asia and the North Pacific in the PMIP2 coupled model simulations W. Yanase and A. Abe-Ouchi1, Clim. Past, 3, 439–451, 2007 Now we can thump the table with a "Fools, they're all wrong", but, fortunately I also found new empirical data from the tropics (thanks Google) from last year. All engineers love empirical data (it works and is normally easy to understand) and this shows that during the LGM the T gradient was higher (possibly because it was drier) at 6.7 C/1000m (up to 3000 m), they also show/model that the tropical SST was only 1- 2C cooler than present and that their modeling (using -135 m as msl LGM) thus gives the recorded T by adding in the lower T due to the higher altitude as patm at their mslLGM is pretty much the same as the present: SCIENCE ADVANCES tropical lapse rate steepened during the Last Glacial Maximum Shannon E. Loomis,1 James M. Russell,1,2* Dirk Verschuren,3 Carrie Morrill,4,5 Gijs De Cort,3,6 Jaap S. Sinninghe Damsté,7,8 Daniel Olago,9,10 Hilde Eggermont,3,11 F. Alayne Street-Perrott,12 Meredith A. Kelly13 I have been in contact with Dr Loomis to check on o few points (their graph actually shows a T drop of about 1.4 C between msl LGM and mslP).and how they chose patm at mslLGM. And now we get to the part that is of real interest. The fuzzy thinking (a bagunça) concerns most comments on cooling during the LGM. Normally this is termed as "over patagonia T were some 5-7 C cooler" or "in Southern Brazil T were 5-7 C cooler"... These should have the caveat: OVER PRESENT LAND. Down on the new coast (msl LGM) it was a bit warmer - between 1 to 2 C at -120 m - say 5- 3 C cooler in S Brazil (I think we can all agree on this?) and thus closer to the tropical SST. This has a huge impact on the forests that grew on exposed lands (pls check the late ref on the Atlantic Rain Forest which gives an idea of this part of the world) and would thus allow forests to develop further to the S & N. An estimate of the Carbon in these forests (crude & simple) is given in the post. It seems to be significant and this Drowned Forest Effect seems to have been overlooked. Possibly because it really did dissapear in a geological blink into thin air leaving little hard evidence behind (except perhaps a warming pulse from CO2 & a lot more water vapour and thus more clouds/wracks) . Looking at these issues and comments I found that the paper on the Atlantic Rain Forest may even be conservative in the S range of this biome. The W part of the Malvinas Current would have been a lot weaker (due to the exposed lands) and thus the exposed Argentine shelf may have been warmer and wetter, allowing for the spread of the ARF to the Plate. Big area and more Carbon. I'll take this up with the guys working on this and we shall see if this leads to anything of use. So thanks to all for the feedback and interest! Alan

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