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Comments 301 to 350:

  1. Is warming in the Arctic behind this year's crazy winter weather?

     One Planet Only Forever and Michael Sweet

    Moderator I took you up on your suggestion

    It would appear that the 30 years was a typo and it should have read 40.

  2. 2018 SkS Weekly Climate Change & Global Warming News Roundup #5


    The anticyclone you're talking about affected not just NZ. The whole east of OZ have been under the same heat stress. In NSW, it was maybe not as hot but extremely humid for some 2 weeks, making the wet bulb temp unusually high and unconfortable. The nighttime lows, running at 24-25 degrees with 100% humidity were the most terrible part of the conditions because you could not sleep. In Melburne VIC, last sunday night, during evening tennis final starting 8pm, they must have applied extreme heat policy and close the roof of the arena. This was an unprecedented decision, because this is an outdoor event and with the exception of couple daylight matches in extreme heat of 40+ played in recent years, the roof is meant to stay open. Both fans and at least one player were unhappy that the playing conditions were so distort, unprecedented final in OZ open history. But if you check the weather data in Melbourne at 8pm that evening, you note that it was 39 degrees and some 50% humidity and wet bulb conditions were unprecedently exceeded so organisers acted according to their rules.

  3. 2018 SkS Weekly Climate Change & Global Warming News Roundup #5

    I live in Auckland, New Zealand, and the artcle sums things up well. Its certainly been a rollercoaster ride of weather.

    Just a couple of additional points. We have had about a couple of weeks of heatwave conditions, mainly in the south island, due to la nina conditions, and large southerly anticyclones leading to unusually warm oceans well above the norm. Last years temperatures were also one of the hottest in our history due to climate change. Not sure how this year is tracking, but it certainly feels well above average temperature for January, but fortunately mostly low humidity in Auckland.

    A few days ago the heatwave collided with the remnants of a tropical cyclone from the north, causing significant wind damage and flooding in the south island, and higher than anticipated. It was a small tropical low moving down, however it then gained intensity due to the very warm oceans right near NZ's coast.

    We also sometimes get tropical cyclones getting right down to NZ , eg Cyclone Bola.  Climate change is expected to increase the strength of tropical cyclones that reach NZ, according to NIWA, as oceans warm.

    The heatwave ended a couple of days ago, with low pressure cells and fronts over the country and colder southerly air masses dominating. Night time temperatures have dropped about 8 degrees in Auckland. The change has been quite abrupt.

    I recommend Dyson fans. Incredibly strong air flow and quiet.

  4. There's no empirical evidence

    "the fact that the earth has been warming for the past 20K years"

    As the mod's note, that claim is incorrect.  The facts are, increasing carbon pollution has ended the era of stable climate.

    Per Marsicek et al 2018:

    "amplified warming in recent decades increased temperatures above the mean of any century during the past 11,000 years"

    Fig 2

    Fig 2 Legend


    And, per the discussion at Think Progress:

    during the last 5,000 years, the Earth on average cooled about 1.3 degrees Fahrenheit — until the last 100 years, when it warmed about 1.3 degrees F.


  5. It's not okay how clueless Donald Trump is about climate change

    The American Meteorological Society has commented:

  6. There's no empirical evidence

    Global warming is a fact, but the title of this article is misleading and unhelpful to the cause. It's typical in any debate that both sides overstate their claims. I regularly see and hear the claim that humans are causing global warming, but that doesn't recognize the fact that the earth has been warming for the past 20K years. What is true is that humans are CONTRIBUTING to a climate change that is already underway. In some respects that is even more scary. 

    Moderator Response:

    [TD] Your claim is incorrect. See the post on the wheelchair, and then the post on PAGES 2K. Then read Zeke Hausfather's post including a graph of natural versus human influences. And the Advanced tabbed pane on the post about the human fingerprint.

    [JH] The use of all-caps constitutes shouting and is prohibited the the SkS Comments Policy.

  7. One Planet Only Forever at 04:02 AM on 3 February 2018
    Is warming in the Arctic behind this year's crazy winter weather?


    Some additional reasons to consider the original statement you question to be reasonable based on my suggested considerations:

    • The sun does not shine on any part of the actic during the winter months. So the summer month ice cover is the key to how much solar warming of Arctic waters occurs. Also, the ice cover during the winter keeps more of that that heat in, though the ice is thinner making it likely that soon 2012 will no longer be the record.
    • The time duration between 2012 and 1992 is only 20 years.

    Combining those two points it is reasonable to expect that in 2022 the Arctic Sea Ice minimum area will be about 50% of the mean minimum for the period from 1979 to 2006 (2016 and 2017 were pretty close to that lower value).

    I hope that helps you change your mind.

  8. It's not okay how clueless Donald Trump is about climate change

    nigelj @ 3

    Nigel, I think you will find Fire and Fury very interesting.  It is a fascinating description of the tug of war that has happened in the Trump administration between 3 factions to get "the ear" of The Donald.  Bannon representing the "alt right", Preibus representing the RNC, and Jarvanka (Jared and Ivanka) representing a somewhat Democrat viewpoint pushing in front of Trump a litany of CEOs that Jared would like to get to know better.

    Watching all of the recent information regarding Hope Hicks and the Nunes memo which is presently in the press makes more sense having read the book.

    This book is much more than a few "off the record" quotes from his entourage on what he is really like.

  9. It's not okay how clueless Donald Trump is about climate change

    Also => President Trump’s claim of growing ice does not reflect reality

  10. One Planet Only Forever at 16:18 PM on 2 February 2018
    Is warming in the Arctic behind this year's crazy winter weather?


    Statistically, the mean of the Arctic Sea Ice extent for the period 1979 - 2006 is not the value in 1992 (or 1993 - the other middle year of the set of data).

    And 2012 is cleary just the current record low that is expected to be beaten in the near future. The trend of the Arctic Sea Ice extent is headed that way.

    However, all I offered was another way of validating how reasonable the statement you question was. To me it appears reasonable 'as is' in spite of the qualifications you raise.

  11. Is warming in the Arctic behind this year's crazy winter weather?


    I saw that the average of JAS was not a 50% decline but I do not have a copy of September only.  The decline is more in September than in July or August so the decline in September from 1950-1979 must be greater than 20%.  Dr Francis would have the exact data needed. 

    The data I have presented show that the sea ice started its decline long before 1979 and using only the satalite data grossly underestimates the decline.  Since September has declined 40% over the satalite era it is clear that the total September decline is over 50%. 

    It is not Dr Francis problem if other people do not know the facts she uses in an article for the general public.

  12. It's not okay how clueless Donald Trump is about climate change

    Clean coal = We give it a warm bubble bath before burning it.

  13. Is warming in the Arctic behind this year's crazy winter weather?

    michael sweet@10,

    Eyeballing your graph for the most dramatic period (JAS) of decline, the trend from ~1950 to 2010 would be from a bit less than 12 (11.5)to a bit over 6 (maybe 6.5), so less than 50%, proving Alchymist correct. Maybe you meant the Sept only graph to better illustrate your point. But it's unclear what data fairly represents the point Jennifer was making.

    The bottom line is Jennifer may want to be more precise next time even though she does not need to be in such non-scientific article.

  14. It's not okay how clueless Donald Trump is about climate change

    Addendum: By clean coal I assume Trump means burying the CO2 emissions underground etc. But who knows what he means, I doubt he knows himself half the time. 

  15. It's not okay how clueless Donald Trump is about climate change

    Chriskoz @2

    Trump certainly has a history regarding racial issues. For example from the NY Times we have some detailed evidence: "Donald Trump’s Racism: The Definitive List"

    Yes clean coal is just deceptive nonsense that will never happen. He could start implementing this today if he really wanted, but has done nothing. Not that I'm advocating clean coal, because renewable energy now makes more sense. 

    I feel just as strongly as you about Trump, but I just function better if I'm a bit restrained in comments. Just bought the book Fire and Fury. 

  16. Is warming in the Arctic behind this year's crazy winter weather?


    Mod [PS] responded to the substance of the issue you raise & I have nothing to add.

    However, I'm curious why you "sic" michael sweet's name. My understanding is that "sic" is used to warn about deliberate misspelling, e.g. due to quoting someone else's mistakes or another dialect.

    Deliberate misspelling of someone's name is a personal offence, so should never happen and you did not misspell michael's name. So "sic" does not make sense here unless you wanted to use it in a meaning that I don't know.

    Moderator Response:

    [JH] Michael Sweet mispelled Alchemyst. Please let the Moderators do the moderating. Thanks.

  17. Is warming in the Arctic behind this year's crazy winter weather?


    You are cherry picking your start year as 1979.  That is when satalite records start, but not when scientific records start.  This graph from Cryosphere Today

    sea ice area

    Indicates that the sea ice decline started around 1950.  The sea ice declined about 20% between 1950 and 1979.  (the averages for the entire summer changed 20%, the minimum generally changes more than the average of the entire summer),  Since the decline from 1979 to the average of the 2010's is about 40%, when you add in the decline from 1950 the  total decline is substantially greater than 50% since 1950.

    Dr. Francis is referring to the decline in sea ice known for the entire record, not for a cherry picked interval that starts long after the decline in sea ice is known to have started.

    Moderator Response:

    [JH] You are addressing Alchemyst. not Alchymist.

  18. Is warming in the Arctic behind this year's crazy winter weather?

    One Planet Only Forever, taking a mean for 1979 to 2006 and comparing it to the result of 2012. The "mean" year would be 1992 which makes 30 years to 2012. And 2012 had half the cover of the mean. 

    Yet 2012 was an outlier and so this is very bad statistics.  So the declie is less than 50% in 30 years, thank you.   Please note that the  September data shows the greatest decline for any of the months and as I stated earlier   it is 13.7% per decade which gives 41% over 30 years.  

    The ice cover loss for other months can be as low as 8% in 30 years (please see the April 2017 bulletin).

    No 50% without qualification in my opinion is exagerated and alarmist and does not help in the overall discussion.

    Moderator Response:

    [PS] This article is a repost from "The Conversation" and we dont have contact with the author. While I agree that overstating the case is not good, Sks is not going to be altering the text of a repost. It might be better if this point is raised over at "The Conversation". The author is only person really able to talk to the point - everyone else is guessing. Whether the change is 30-40-50% is also a little irrelevant to the main point of this article which was to look at the way arctic changes can affect weather further afield.

  19. It's not okay how clueless Donald Trump is about climate change


    T-man resents Obama because t-man is a racist. Proof: he instructed his hotel staff to tag black people on their job applications and was telling black customers "no vacancies" while admitting whites at the same time.

    The article describes well the t-man's ignorance but IMO it does not go far enough. E.g., t-man's talk about "beautiful clean coal" is no more than a moronic, childish, deceptive quirk to gather behind him the voters who lost their jobs due to coal mining collapse. No one listens to it, and those unemployed miners should stop listening ASA they realize other, cleaner jobs do exist.

    Perhaps Dana restrains himself, because the office of POTUS is very honorable (sic, I live in OZ) and requires respect. But it's hard to have any respect to the childish soap opera show that t-man turned this office into.

  20. Is warming in the Arctic behind this year's crazy winter weather?

    Thanks michael sweet (sic) at 7:35, the result is due to using the 2012 result which was exceptional. This is caled cherry picking and does not credit the site. If you are using the 2012 value as representative then there has been an increase in the arctic ice cover over the last 5 years. 

    The University of Colorado state that the cover loss is 13.2 % liear per decade for the most extreme month. If one takes the 2012 result as a point in calculation then the conclusion is that the ice cover is now increasing! 

    michael the 2012 result was an outlier and should not be used as a representative of the real slution which is of a steady decline with significant scatter.

    Here is the data, just take 19996 and 2012 results in isolation and you can get 50%, but at my shool were were taught that doing that was naughty.

    I gave you a reference to probably the best data that of the Universty of Colorado

  21. One Planet Only Forever at 09:05 AM on 2 February 2018
    Is warming in the Arctic behind this year's crazy winter weather?


    The total ice area evaluation presented by Arctic ROOS shows a minimum ice area for the 1979-2006 data set of 6.0 x 106 km2. The minimum for 2012 was slightly less than 3.0 x 106 km2, which is a loss of 50% of the ice area. The 2016 minimum was about 3.5 x 106 km2 which is not quite 50% below the median of the 1979 to 2006 data set. And 2017 was a little higher. But the trend is not an increase of Arctic sea ice extent.

    On a related point about the future of the Arctic Sea Ice, the total mass of Arctc ice is evaluated in this PIOMAS Arctic Sea Ice Volume Reanalysis by the Polar Science Center which shows that the average Arctic ice is getting significantly thinner making significant near future reductions of minimum sea ice extent more likely to occur.

    A final point about how much the Arctic extent has been reduced. The reference in the OP could be regarding the reduction from the earlier values in the 1979 to 2006 data set, which may have been higher than the median, and high enough that the 2017 area of sea ice is 50% less than the minimums in the early years of the 1979 - 2006 data set.

    Moderator Response:

    [JH] You are addressing Alchemyst. not Alchemist.

  22. In 2017, the oceans were by far the hottest ever recorded

    sidd @6,

    The missing energy is as described by scaddenp @7&9. And the basic numbers set out by Incognitoto @RealClimate are fine although some of the subsidiary numbers are well off the mark.

    Incognitoto is suggesting the net climate Forcing back 10-15 years ago was +1.6Wm^-2 (which is possible) which he equates to an energy imbalance of 800TW (actually 816TW) and that would be 25Zj/yr. He also speculates about today's net Forcing being +2.0Wm^-2 but goes nowhere with it.

    Incognitoto then suggests ΔOHC would have been 8Zj/yr, so accounting for a 250TW energy imbalance. The 0-2000m ΔOHC for 10-15 years ago (from NODC/NOAA although they don't list back to 2003 for 0-2000m any more. The earliest 5 years comes to 43.7Zj ΔOHC between 2005 & 2010) gives 39.3Zj ΔOHC between 2003 & 2008. That yields 7.86Zj/yr or a 249TW energy imbalance.

    Incognitoto adds on "less than" 10TW for melted ice and 40TW for added atmospheric H2O. The Ice estimate is probably about right for 10-15 years ago. 10TW would equate to 950Gt/yr of melt. GRACE data for Greenland & Antarctica (graphed here) suggests about 400Gt/yr. And according to PIOMAS Arctic Sea Ice would add about 300Gt/yr and a similar amount from other glaciers. The H2O is badly wrong. It would be about 2.4TW with an additional 3.0TW heating up the air. A final component is the heat required to warm the land which would be roughly similar in size to Ice & Atmosphere. (Note the SkS graphic here dates back to 2007 would predate GRACE results.)

    So the energy flux back 2003-08 exiting planet Earth to space due to the AGW temperature rise (if the 1.6Wm^-2 is accepted as a net Forcing) would be something like 525TW.

  23. Is warming in the Arctic behind this year's crazy winter weather?


    Idle claims that the sea ice expert who wrote this article was incorrect are easily dismissed with actual data.

    To answer your question: "could someone please explain this disepancy [sic] or is it due to inflation and projection?"

    The discrepancy is due to the asker being uinformed of the actual data.  The linked article was a summary article and did not detail all the sea ice data.

  24. Is warming in the Arctic behind this year's crazy winter weather?


    Perhaps the author was referring to the fact that from 1979-1989 the minimum daily extent was 7.0 million Km2 and the minimum in 2012 was only 3.3 million km2.  data link  (sorry, I couldn't get the graph to link).  That is a decrease of more than 50% where I went to school.  Sea ice area decreased from about 5.5 million km2 to about 2.3 million km2, also more than 50%.

    Monthly minimum volume has decreased from 16.5 thousand km3 to 3.8 thousand km3. (first data link above)  Since that is a decrease of more than 75% she was probably not referring to that change. 

  25. It's not okay how clueless Donald Trump is about climate change

    Well said. Trump is just clearly totally scientifically ignorant, and you can probably add in some deliberate stupidity. He doesnt like carbon taxes, and renewable energy etc so he attacks the science.

    He is excessively prioritising corporate values above the environment and public good. This is clear in everything he has done since being in office legislatively, so his words claiming otherwise are fake words.

    Clearly Trump doesn't like multi party agreements. He is used to negotiating two party property deals, and multi party agreements are foreign to him. It's not so easy for him to dominate and manipulate people in multi party agreements.

    Trump has pulled out of the TPPA, which is a multi party trade agreement. America was dominating this agreement and getting the best deal, so his move makes little sense. However Trump has opposed free trade for a long time, despite the fact nearly all economists promote free trade.

    Trump also obviously hates and resents Obama. This appears almost pathological.

    America is lost, and it's people mostly don't seem to care anymore what made up nonsense their politicians talk.

  26. Is warming in the Arctic behind this year's crazy winter weather?

    Alchemyst @2

    "Quoting the acticle it states that "losing half the arctic sea ice cover in 30 years". Following the reference the original acticle in Review of Geophysics, by WM Meier et states "Over the past few decades, summer areal density has declined over 30%.....Exagerated claims dscredit the site. "

    Perhaps the writer added the 30% decline in sea ice area to the 40% decline in thickness to say the arctic has lost half the sea ice 'cover' in 30 years. Just a guess on my part.

  27. Is warming in the Arctic behind this year's crazy winter weather?

    It is reasonably likely that this is a transition phase.  When the Polar Hadley cell finally reverses for longer and longer periods, we should see climate zones rapidly move northward and all of Northern America warm considerably.  Right now, Polar air can make it's way south as the Polar Hadley cell weakens and is no longer confining Arctic air to the Arctic but this should change as the sea is more and more open water.  At least there is one positive in all this.  As heat is drawn northward, just possibly enough heat will be removed from southern waters to save our coral reefs.  Not much of a comfort if the  Northern Hemisphere grain belts are destroyed.

  28. Is warming in the Arctic behind this year's crazy winter weather?

    Quoting the acticle it states that "losing half the arctic sea ice cover in 30 years". Following the reference the original acticle in Review of Geophysics, by WM Meier et states "Over the past few decades, summer areal density has declined over 30%.

    So going to the Arctic sea ic website from the university of colorado we get in their oct 2017 bulletin "The linear rate of sea ice decline for September is .....13.2% per decade.

    Now the greatest decline is found in the summer, but this auhor seems to have increased his by 10 or 20 % and not mentioned that the winter decline is much less about 15% over 30 years.  

    Exagerated claims dscredit the site. 

    could someone please explain this disepancy or is it due to inflation and projection?

  29. One Planet Only Forever at 04:36 AM on 2 February 2018
    In 2017, the oceans were by far the hottest ever recorded


    A Top 5 (or Top 10, or Top anything) list should never be presented in 1,3,2,4,5 order.

  30. In 2017, the oceans were by far the hottest ever recorded

    Thegraph slows a slight reduction in heat in year 2016.  Just below that we see the "top five" listed by joules.  At first glance it looks like a steady upward trend until one notices the years 2015 & 2016 are "flipped".

    My choice would have been to list the top five in year to year sequence so "first glance" would not have given the impression that its up, up, up, up up

    Some of you are probably thinking "swampfox doesn't have anything to do today"  and I probably don't.


  31. In 2017, the oceans were by far the hottest ever recorded

    I havent done the calculation, but I believe the diagnotic from OHC is that ERB is 0.8w/m. Incognitoto seems to believe it should same as change in delta-F.

  32. In 2017, the oceans were by far the hottest ever recorded

    Sidd @6 , I haven't checked the calculation figures offered by RealClimate poster "Incognitoto" — but I am not sure where you see a problem.

    Effective radiative forcing has increased from 1 watt/sq.m. at approximate date 1975, up to 2 watts/sq.m. by 30 years later.

    Was poster "Incognitoto" referring to Ocean Heat Content in the surface 700m of the ocean, or in the surface 2000m [as mentioned in this particular SkS article, or in the total ocean?

    And was he allowing for the temporary reductions (in radiative forcings) caused by major volcanic eruptions?

    All in all, there seems no reason to doubt that "over 90% of radiative imbalance" is going into the oceans.

  33. In 2017, the oceans were by far the hottest ever recorded

    I may have misunderstood the question, but there seems to be some confusion in the maths over change in forcing versus change in ERB. As earth has got hotter, much of that 500TW is going irradiated again. The non-zero ERB is because oceans are burying heat.

  34. In 2017, the oceans were by far the hottest ever recorded
    Over at realclimate, there was a question posed: Over 90% of radiative imbalance is supposed to go in the oceans. But OHC increase is considerably smaller. So where is the heat going ?

    Anyone care to comment ?


  35. One Planet Only Forever at 04:05 AM on 1 February 2018
    Is warming in the Arctic behind this year's crazy winter weather?

    Increased awareness and better understanding can occur. Some people are willing to change their minds for Good reason.

    However, anyone who already believes that global average surface temperature warming by 2 degrees C means the end of cold weather (many claim this) is unlikely to be willing to understand that global warming can produce more frequent cold events that are not quite as cold as, and may be snowier than, the less frequent cold events used to be.

    The power of Private Interest in personal benefit can develop some very persistent damaging beliefs (like the belief that the popular and profitable burning of fossil fuels cannot possibly be unsustainable or harmful because, as those Economic Masters of Misunderstanding would declare, "if it was actually harmful or unsustainable it couldn't be popular or profitable").

  36. They changed the name from 'global warming' to 'climate change'

    John: your link at #26 just points back to

    Moderator Response:

    [JH] Glitch fixed. Thank you for bringing it to my attention.

  37. Ocean acidification isn't serious

    Recommended supplemental reading:

    Scientists Pinpoint How Ocean Acidification Weakens Coral Skeletons, News Release, Woods Hole Oceanographic Institute, Jan 29, 2018

  38. One Planet Only Forever at 09:45 AM on 31 January 2018
    New research, January 15-21, 2018

    John S@3,

    Burning wood does not increase the carbon in the recycling surface environment the way that burning fossil fuels does. However, all results of the entire activity needs to be included in the evaluation. That would include the other pollution created when wood is burned. It would also include any pollution related to the building and production of competing renewable energy systems.

    Other considerations would include the impacts of deforestation or impacts of renewable enegry systems on other life in the diverse web of life that humans have to sustainably fit in to in order to have a future.

    Another consideraton regarding biomass is if it displaces food production. Using inedible vegitation from food production would be positive. Displacing food production to 'make energy' would be a negative.

    Not sure where wood burning or biomass would end up in a comprehensive evaluation of true sustainability. It would probably be the winner in many locations.

    The more important point is that evaluating the true sustainability of any human activity must be the basis for allowing it to be considered to be an acceptable participant in the games of competion to win popularity and profitability.

    The failure to restrict what is allowed to compete for profitability and profitability undeniably leads to unsustainable and damaging activity Winning because of the 'competitive advantage of the cheaper and easier ways that can be gotten away with'.

    Admittedly the current challenge is that people peceiving themselves to be the biggest Winners understand that they have the most to lose if what has incorrectly developed actually gets corrected. The faster the correction the more they lose. And of course those undeserving Winners stand to win more by fighting against any correction occurring in their wealth-pursuing lifetime that negatively affects their wealth-pursing opportunities.

  39. They changed the name from 'global warming' to 'climate change'

    Recommended supplemental reading:

    Debunking the claim ‘they’ changed ‘global warming’ to ‘climate change’ because warming stopped by Jason Samenow, Capital Weather Gang, Washington Post, Jan 29, 2018

  40. 2018 SkS Weekly Climate Change & Global Warming Digest #4

    Few people that support Trump can adequately explain global warming, even the basics. Just hand one you know in real life a sheet of paper with a semi-circular "sun" on the left and "Earth" on the right, and watch them utterly flounder to explain even the least of the basic ideas underlying the theory.

  41. 2018 SkS Weekly Climate Change & Global Warming Digest #4

    The power of marketing. Facebook designed to be addictive:

    Phones, cars, and high carbon consumption all the same. Designed and marketed to be addictive.

  42. Plant stomata show higher and more variable CO2 levels

    qwertie @12,

    Middleton's five-point graph simply mis-places the averaged point by plotting them against the date of the last of the five measurements. So his final five-point average is 334ppm plotted against 1988 when it should be plotted against 1927 when the ice core measurements suggest it would have been just topping 300ppm.

    The stomata data comes from Kouwenberg et al (2005) who plot 3-point averages (& the final 1988 plot as a singleton) with single-point confidence intervals +/-40ppm, as shown in Fig 4.4 in this PDF.

  43. One Planet Only Forever at 01:42 AM on 30 January 2018
    2018 SkS Weekly Climate Change & Global Warming Digest #4

    The likes of Trump are reacting to the environment they developed in. Their unjustifiable attitudes and actions are encouraged to develop in competition to 'appear to be superior to others - any way that can be gotten away with'.

    Popularity and profitability are lousy measures of acceptability.

    The reality is that there are many people with over-developed and unsustainable perceptions of superiority, prosperity and opportunity. They are the reason that serious action to correct the direction of economic development did not occur when the unsustainable and damaging reality of the unanatural economic developments was identified decades ago.

    Humanity's only path to a sustainable future requires low-tolerance for people who are Big Winners to deliberately be incorrectly aware or misunderstand important understandings. Those types of undeserving winners need to be Losers until they 'Learn to Care to Change Their Minds'.

    This is not Rocket Science. Any business that would allow its Leaders to be incorrectly aware or misunderstand what is actually going on has no real future. Any perception of Winning those types of Winners/Leaders develop will never last. Unfortunately they can do a lot of damage if their removal from influence is delayed by Successful Poor Excuses (Good Reason would remove them from their Winning - only Poor Excuses can support them as Winners).

    The early thinkers about free market capitalism who were concerned about the potential for marketing to distort things and develop damaging results were clearly correct (many early thoughts in England were that advertising should be restricted to the inside of the shop that was selling an item or service - no mass-marketing allowed).

  44. Plant stomata show higher and more variable CO2 levels

    Sorry for having the wrong image width - I noticed the problem as soon as I posted it but there is no edit button on comments. As I've proposed before, you can fix image widths automatically with CSS like `#comments img { max-width:99%; }` or suchlike. If I understand correctly, this rebuttal is about a graph by Indermühle et al, research by Wagner et al, and an interpretation of Wagner's data by Middleton. The link under 'climate myth' points to an article by Middleton with numerous graphs, one of which is the one I reposted.

  45. Plant stomata show higher and more variable CO2 levels

    So Middleton would like his followers to trust a source that says CO2 was at about 373ppm in 1960, whereas direct measurements of the atmosphere say it was about 315 ppm, while 21st century satellite pictures (AIRS) show only 10-20ppm variation across the globe.

    It's tempting to quibble with his other claims and insinuations... for example "show me an AIRS image that shows the polar regions to have higher CO2 levels than the mid and low latitudes" - look, humans emit most of their CO2 from the northern hemisphere so it can takes a few months for it to reach Antarctica. This is very clear by watching an AIRS time-lapse video, where anyone can see what's going on. Weather patterns do occasionally cause mid land low lattitudes to have roughly the same CO2 as Antarctica, though. Clearly AIRS does not justify the position that Antarctica had lower CO2 before humans came along! But no matter how much we quibble with Middleton, people that want to believe that "nature" quickly raises and lowers CO2 "at will", without human influence, will take his word as gospel.

  46. Plant stomata show higher and more variable CO2 levels

    The image in this rebuttal is broken (embedding an image from another web site is a dangerous thing to do). I think the image was supposed to be this one:

    Legend: Taylor Dome (⋄), Vostok (□); top: Stomata

    "This figure shows that Wagner's data shows a sharp increase to 330ppm at 11,260 years BP (years before 1950), staying there for 500 years, in disagreement with the Taylor Dome and Vostok ice-core records." Keep in mind that time flows leftward on this graph.

    It should also be noted that Taylor Dome is not the highest-resolution ice core record available, and that Middleton himself published this graph showing Stomata disagreeing with direct measurements of atmospheric CO2 and high-resolution ice cores in the 20th century:

    (His 5-point moving average, by the way - the final point doesn't make any sense because you need 5 points to create a 5-point moving average, so which 5 points is the final point based on? Also, it's much lower resolution than the ice cores, and it's not a consistent time unit since the spacing of the red triangles is uneven.)

    Moderator Response:

    [DB] Please limit image widths to 450 to avoid breaking page formatting.  Thanks!

    [PS] Middleton's "published" graph (linked under climate myth at top of the article) is what this rebuttal is about.

  47. From the eMail Bag: A Deep Dive Into Polar Ice Cores

    Great comments/questions, qwertie. You said: "not a single climate scientist, including any of the contrarians (the 3%), has thought of any way that CO2 could disappear from the atmosphere as quickly as it has been added."

    Exactly. Which is what Dr. Buizert was saying. A sudden spike in CO2 would leave a mark in the record because everything we know about the carbon cycle tells us that the spike wouldn't "quickly disappear". Also, a sudden CO2 spike would have other effects on the ice core records: they would show a spike in temperatures which are also measured in the ice cores.

    Your skeptic, in your example, wants to just look at the ice core CO2 measurements in isolation, without taking into account what is known about the carbon cycle.

    You said: "Unfortunately this article isn't clear enough to draw such a conclusion. One way it would be more clear is if it gave at least one example to demonstrate how to calculate the gas age distribution."

    Finding the "age distribution" isn't a very straight-forward process. This is all rather complicated stuff and I confess not to have a complete grip on all of it...especially all of the math involved. But conceptually I think I understand it (mostly). I'll try to explain it, but you may want to check the papers yourself. I would suggest these (you can find the links to them above in my list of refs.): Etheridge et al. 1996, Trudinger et al. 1997, Marcott et al. 2014. Also this one not listed: Buizert et al 2015.

    When I was corresponding with Dr. Buizert I asked him where I could find age distributions for the various ice cores. He said that they are better known for firn air but not for the older air trapped deeper and deeper in the ice core bubbles. However the Delta-ages of ice cores are easier to find (see Figure 6 in OP), hence his "short-cut" for finding the age distributions: Δ-age x 5% = age dist.

    Here is how these various things are related:

    ice age - gas age = Δ-age

    "Ice age" is easy to find, it can be found simpy by counting the layers in the ice core, like counting tree rings. And it is possible to tie this count into our calendar years by noting specific points in the core, like a layer of volcanic ash from an especially large and known volcanic eruption.

    For the "gas age", we know that the air in bubbles is younger than the surrounding ice (described in the OP). But how much younger? Well that depends on the conditions (amount of snow accumulation and temperature) at the ice core location, and how long it takes for the bubbles to get "locked in" through the lock in zone. So to find the "gas age" scientists work backwards from the equation above, they start by calculating the Δ-age.

    They find the Δ-age by using mathematical models using the specific firn conditions of the ice core location. With the modelled Δ-age and the known ice age, they can then use the equation to find the gas age. Here is an example of this technique, as described in the Marcott et al. 2014 paper from my ref. list:

    "Gas ages were obtained by subtracting a modelled ice-age/gas-age difference (Δ-age) from the ice-age timescale. Δ-age was calculated using a dynamical firn-densification model with heat diffusion. The modelling is constrained by measurements of δ15N of N2, a proxy for past firn column thickness."

    Let's say, for example, that our firn model gave us a Δ-age for the Law Dome ice core of 30 years. That means there would be a 30 year difference between the ice age and the gas age. Look at Figure 4 of the firn cross-section. The 30 year Δ-age is basically the time it takes for the top snow layer to get buried and eventually reach the close-off depth. At that depth any air in the ice is locked into bubbles and is closed off from further contact with the air in the firn above which is open to the atmosphere.

    Back to Law Dome, a 30 year Δ-age is the actual value found in Etheridge et al. 1996. Here is a table from that paper:

    Law Dome Dating ParametersNotice the last column: "Duration of Bubble Close-off Process". This is another way of describing the "age distribution" of the gas within the bubbles. Look again at Figure 4 of the firn cross-section. The bubble close-off process takes place in the "lock in zone". The length of time it takes for the air to become finally trapped in bubbles in the lock in zone defines the "age distribution". This is different for every ice core location, again, depending on snow accumulation, temperature, firn density, etc.

    The time in the lock-in zone is roughly 10% of the time span given by the Δ-age. (But, again, this rough approximation would be different for each different ice core location.) So yes, the age distribution of the gas is directly related to the Δ-age. Hence, the quote from the Mitchell paper:

    "The bubbles are known to close off over a vertical ice age range [the Lock-in Zone] that corresponds to roughly 10% of the gas age-ice age difference, which intuitively should result in a gas age distribution width corresponding to 10% of the gas age-ice age difference [the Δ-age]. However, the observed smoothing of the trapped gas record often appears to be less than would be expected from this rate of gradual bubble closure."

    And my further comment: "So rather than 10%, a good rule-of-thumb, according to Dr. Christo Buizert, is to take 5% of the Δ-age to find the age distribution."

    Back to Law Dome, again. Ten percent of the 30 year Δ-age would give an age distribution of only 3 years, not the 8-15 years I alluded to from Figure 5. Well, like I said, these are rough approximations.

    The main point is to simply realize that the date of the CO2 in ice core bubbles cannot be pinpointed to a single year in the past. There is an age distribution or range of years that the gas is dated to. It may be very difficult to determine the exact width of a given ice core's age distribution, i.e. the span of years in the distribution, but we can get in the right ballpark.

    Moderator Response:

    [DB] Please limit image widths to 450 to avoid breaking page formatting.  Thanks!

  48. 2018 SkS Weekly Climate Change & Global Warming Digest #4

    "After proclaiming his belief in “clean air and clean water”, the US President questioned some of the central tenets of climate science in an interview with Piers Morgan."

    Despite this, Trump has begun dismantling Obama’s clean water rules. The contradictory,  two faced nonsense he speaks is just incredible.

    "The ice caps were going to melt, they were going to be gone by now, but now they're setting records. They're at a record level."

    Some people like Trump have great difficulty separating out short term climate noise, for example a one year 'recovery' in ice levels,  from longer term trends of declining ice cover. I dont know why, and with Trump he just seems to take simple statements on face value if he likes the person delivering the message. Or perhaps some people just have trouble differentiating between short and long term trends, and I'm becoming increasingly convinced of this.

    Or perhaps some people resent carbon taxes and government rules, and lifestyle changes, so deny the science, possibly without even realising they are doing this.

    I havent really seen any investigation claiming a single reason stated for the climate denial, and it may just be a combination of these things.

    There are of course much blunter ways of putting all this.

  49. In 2017, the oceans were by far the hottest ever recorded

    New Zealand currently has a heatwave, due to a combination of warm oceans, la nina conditions, and a stalled jet stream that is keeping colder southern air away, while northerly  tropical air flows down. We have set a record for the hottest January in history.

    I bought one of those Dyson fans (actually a fan heater, so I can use it in winter as well). I recommend this device. It's expensive, but has a very powerful fan with a focused stream of air, and a quiet fan.

  50. 2018 SkS Weekly Climate Change & Global Warming News Roundup #4

    Climate change is making the planets climate more tropical. The tropics have more diseases. Warmer climates have more biodiversity, so more animals and bugs, and warmer climates are ideal for laying eggs.

    Some basic form of universal healthcare makes sense. Because nobody in their right mind wants to see desperate sick people unable to afford even basic healthcare, and a healthy workforce benefits employers as well. 

    Government have a fundamental role in environmental protection, because free markets don't look after the environment, because of the tragedy of the commons problem. 

    But not everyone thinks that way. This is because not everyone thinks.

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