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Comments 17651 to 17700:

  1. Hurricanes aren't linked to global warming

    Over the past couple of weeks, I have posted links to the following articles about the climate change-hurricane connection on the SkS Facebook page.

    Did Climate Change Intensify Hurricane Harvey? by Robinson Meyer, The Atlantic, Aug 27, 2017

    Climate change did not “cause” Harvey, but it’s a huge part of the story by David Roberts, Energy & Environment, Vox, Aug 28, 2017

    Could Hurricane Harvey Deal A Fatal Blow To Climate Change Skepticism? by Jared Keller, Pacific Standard, Aug 28, 2017

    Harvey Shows How Planetary Winds Are Shifting by Eric Roston, Bloomberg News, Aug 30, 2017

    Does Harvey Represent a New Normal for Hurricanes? by Robinson Meyer, The Atlantic, Aug 29, 2017

    Katrina. Sandy. Harvey. The debate over climate and hurricanes is getting louder and louder by Chris Mooney, Energy & Environment, Washington Post, Aug 30, 2917

    What Hurricane Harvey says about risk, climate and resilience by Andrew Dressler, Daniel Cohan & Katharine Hayhoe. The Conversation US, Sep 1, 2017

    Three things we just learned about climate change and big storms: Can the lessons of Harvey save us? by Paul Rosenberg, Salon, Sep 4, 2017

    Denying Hurricane Harvey’s climate links only worsens future suffering by Dana Nuccitelli, Climate Consensus - the 97%, Guardian, Sep 5, 2017

    Harvey and climate change: why it won't change minds by Amy Harder, Axios, Sep 5, 2017

    Hurricane Harvey's aftermath could see pioneering climate lawsuits, Analysis by Sebastien Malo, Thomson Reuters Foundation, Sep 5, 2017

    On Climate, Hurricanes, And Growth by Joseph Majkut, Niskanen Center, Aug 31, 2017

    First Harvey, now Irma. Why are so many hurricanes hitting the U.S.? by Nisikan Akpan, PBS News Hour, Sep 6, 2017

    The science behind the U.S.’s strange hurricane ‘drought’ — and its sudden end by Chris Mooney, Energy & Environment, Washington Post, Sep 7, 2017

    Hurricane Irma is one of the most powerful Atlantic hurricanes ever: what we know by Brian Resnick, Science & Health, Vox, Sep 7, 2017

    6 Questions About Hurricane Irma, Harvey and Climate Change by Sabrina Shankman, InsideClimate News, Sep 6, 2017

    President Trump, hurricanes Harvey and Irma are sending you a message, Opinion by Andrés Oppenheimer, Miami Herald, Sep 7, 2017

    What We Know about the Climate Change–Hurricane Connection by Michael E. Mann, Thomas C. Peterson & Susan Joy Hassol, Scientific American, Sep 8, 2017

    As Hurricanes Irma and Harvey Slam the U.S., Climate Deniers Remain Steadfast by Marianne Lavelle, InsideClimate News, Sep 8, 2017

    Ask the Experts: How Did 2 Such Powerful Hurricanes Occur Back to Back? by Annie Sneed, Scientific American, Sep 7, 2017

    Another Way Climate Change Might Make Hurricanes Worse by Faye Flam, Bloomberg News, Sep 8, 2017

    Will Irma Finally Change the Way We Talk About Climate? by David Wallace-Wells, Daily Intelligencer, New York Magazine, Sep 9, 2017

    Irma and Harvey lay the costs of climate change denial at Trump’s door by Bob Ward, The Observer/Guardian, Sep 9, 2017

    Hurricane Irma Linked to Climate Change? For Some, a Very ‘Insensitive’ Question. by Lisa Friedman, Climate, New York Times, Sep 11, 2017

  2. New paper shows that renewables can supply 100% of all energy (not just electricity)

    michael sweet at 83 on "Trump country costs" blog

    I now understand why you commented that there have been questions raised about the cost estimates in the Jacobson study.  In the interests of balance, I would have hoped  that you would have been more clear on how much this study has now been put into question so recently.

    My specific information (although first highlighted by a reread of the Shellenberger article in Foreign Affairs referenced earlier) comes from a recent Scientific American blog which can be found here: https://blogs.scientificamerican.com/plugged-in/landmark-100-percent-renewable-energy-study-flawed-say-21-leading-experts/

    The Scientific American blog states that the National Academy of Sciences in a June, 2017 paper, authored by 21 leading energy researchers, has made  a "scathing critique" of Jacobson's analysis and found that the analysis “used invalid modeling tools, contained modeling errors, and made implausible and inadequately supported assumptions.”

    The largest error is found in  Jacobson's calculations as to how existing and future hydro could provide the "mixed grid" (buffering)  to support wind and solar power when they were not available.  Here is the comment from Scientific American:

    "The most glaring of which is the assumption that U.S. hydroelectric dams could add turbines and transformers to produce 1,300 gigawatts of electricity instantaneously — equivalent to over 16 times the current U.S. hydroelectric capacity of 80 gigawatts. A previous study by the U.S. Department of Energy found the maximum capacity that could be added is just 12 gigawatts — leaving a 1,288 gigawatt deficit, or the equivalent of about 1000 large nuclear or coal power plants running at full power."

    So, as recommended by this article, it would seem a great deal of work remains to be done to determine how we can move from fossil fuels to a source of reliable clean energy.  This article suggests many avenues including a continued examination of nuclear power.

    I would like to discuss EROI and the Weissbach paper and criticisms by Raugei et al.  My plan is to use this stream as well. 

  3. New study finds that climate change costs will hit Trump country hardest

    michael sweet @ 83

    I will take your suggestion and move further comments on the costs of renewable energy to your article that was originally posted based upon the Jacobson study.  Just tried to "link" things and accidentally deleted my comments before posting them so I will not try that again!

  4. Hurricanes aren't linked to global warming

    The article linked to by SingletonEngineer has been repeatedly cited and linked to by more than one mainstream climate scientist who has been interviewed by the media about the climate change-hurricane* connection in recent articles about Hurricanes Harvey, Irma, Jose, and Katia.

    Global Warming and Hurricanes: An Overview of Current Research Results posted on the website of NOAA’s Geophysical Fluids Dynamics Laboratory (GFDL). It was last revised on Aug 30, 2017.

    *North Atlantic basin only.

  5. Climate's changed before

    NorrisM, Electric & Michael Sweet:

    Please take any further discussion of the Medieval Warm Period to the thread of the SkS Rebuttal aricle, How does the Medieval Warm Period compare to current global temperatures?

  6. Denying Hurricane Harvey’s climate links only worsens future suffering

    www.soils4teachers.org/files/s4t/k12outreach/tx-state-soil-booklet.pdf

    Red # 39

    Black gumbo soil is a clay based soil, with very low permeability which is what I meant by not being very absorbent.  This quality of the soil is well known by the locals. This type of soil is not a very common soil type. It is located primarily in a narrow stretch from north of dallas south through the houston area.  

    Moderator Response:

    [JH] Thank you. What is the permeability index of this soil compared to asphalt and concrete?

  7. Climate's changed before

    NorrisM @566 , thank you for pointing out the Chinese multi-proxy historical data study, published only 5 weeks ago (and receiving a mention last month in WattsUpWithThat & other websites too).

    I haven't accessed the full paper, but the Abstract & Conclusion & a temperature chart (per the Chinese Academy of Sciences).

    There were two noteworthy temperature rises shown in the China region, peaking at around year 1100 CE and the second at around 1250 CE.  The peaks were (respectively) 0.4 degrees and 0.5 degrees above the 1851-1950 mean.  In other words they were quite low relative to current world temperatures.   And judging per my eyecrometer, those and the other minor peaks/troughs show only small excursion (from the mean) and showed rather poor temporal correlation with the Mann et al (2008) peaks/troughs — but of course I would be happy to bow to a more rigorous mathematical analysis of that point.

    All in all, there seems to be nothing very startling (or upsetting to mainstream climate science) in the new Chinese study.  Even the "quick to trumpet incompatibilities" WUWT has had little to say about it; and nor was there anything insightful/intelligent/relevant to be found in the attached WUWT comments column [ but no surprise there  ;-)  ].

    As I mentioned in post #565, neither the LIA or MWP "ripples" can detract from the AGW tsunami.

  8. Denying Hurricane Harvey’s climate links only worsens future suffering

    Tom13,

    Houston's soil is a vertisol. (Houston black gumbo)  It actually can absorb up to 12 times its volume in water. 

    However because it swells and shrinks so much from changes in water, it actually has a pretty poor infiltration rate. It swells shut the pore spaces and channels required to infiltrate rapidly.

    We can fix the soil though:

    The Soil
    Science Society of America defines a claypan as,
    “A dense, compact, slowly permeable layer in the
    subsoil having a much higher clay content than
    the overlying material, from which it is separated
    by a sharply defined boundary. Claypans are
    usually hard when dry, and plastic and sticky
    when wet.” Claypan layers hinder root growth
    into the soil, are acidic (pH <5.0), and may
    contain toxic levels of aluminum.
    The roots of eastern gamagrass contain
    aerenchyma tissue, which is tissue with air
    passages (Alberts, 1997). Roots with aerenchyma
    are spongy, with large holes formed by cells either
    pulling apart or disintegrating. These holes run
    longitudinally through the roots. They enable
    roots in flooded soil to transport air from the
    aboveground parts of the plant. W. Doral Kemper,
    retired ARS scientist, explains “aerenchyma
    tissue enables roots to survive and punch through
    the claypan layer when it’s wet, the only time it’s
    soft enough to be penetrated. These roots live less
    than 2 years. But when they die, they decompose
    slowly and help hold channels open for new
    generations of roots, providing gamagrass with
    continued access to water in and below the clay
    pan.”[1]

  9. 30 Climate Lessons I Learned in 30 Years

    Digby Scorgie,

    The key elements in SRI are Mycorrhizal fungi and methanotrophs. Both of which need the beds to dry out to grow.

    As far as wholesale change, yes it is happening. India's rice revolution

    How Millions of Farmers are Advancing Agriculture For Themselves

  10. SingletonEngineer at 16:24 PM on 11 September 2017
    Hurricanes aren't linked to global warming

    On further reflection, it appears that NOAA is suggesting that frequency is essentially constant and intensity is (may be?) increasing over time.

  11. SingletonEngineer at 16:19 PM on 11 September 2017
    Hurricanes aren't linked to global warming

    This is in response to the unfolding disasters in the Carribean and Florida and the fact that this thread is a little out of date.

    Recent relevant update from NOAA:

    https://www.gfdl.noaa.gov/global-warming-and-hurricanes/

    It seems that fresh data and recent analysis haven't changed things much.

  12. Climate's changed before

    Moderator

    Here is the cite requested:

    Advances in Atmospheric Sciences, August 2017, Volume 34, Issue 8, pp 941–951
    Quansheng Ge et al., Chinese Academy of Sciences


    Abstract
    This paper presents new high-resolution proxies and paleoclimatic reconstructions for studying climate changes in China for the past 2000 years. Multi-proxy synthesized reconstructions show that temperature variation in China has exhibited significant 50–70-yr, 100–120-yr, and 200–250-yr cycles. Results also show that the amplitudes of decadal and centennial temperature variation were 1.3°C and 0.7°C, respectively, with the latter significantly correlated with long-term changes in solar radiation, especially cold periods, which correspond approximately to sunspot minima. The most rapid warming in China occurred over AD 1870–2000, at a rate of 0.56° ± 0.42°C (100 yr)−1; however, temperatures recorded in the 20th century may not be unprecedented for the last 2000 years, as data show records for the periods AD 981–1100 and AD 1201–70 are comparable to the present. The ensemble means of dryness/wetness spatial patterns in eastern China across all centennial warm periods illustrate a tripole pattern: dry south of 25°N, wet from 25°–30°N, and dry to the north of 30°N. However, for all centennial cold periods, this spatial pattern also exhibits a meridional distribution. The increase in precipitation over the monsoonal regions of China associated with the 20th century warming can primarily be attributed to a mega El Ni˜no–Southern Oscillation and the Atlantic Multidecadal Oscillation. In addition, a significant association between increasing numbers of locusts and dry/cold conditions is found in eastern China. Plague intensity also generally increases in concert with wetness in northern China, while more precipitation is likely to have a negative effect in southern China.

  13. Denying Hurricane Harvey’s climate links only worsens future suffering

    NorrisM @ 29

    &

    nigelj @ 32

    "The IPCC say theres no clear evidence of whether hurricanes have got worse so far, but the problem is hurricanes are not that common and records of intensity are rough."

    In other words, to assert that the IPCCs predictions cannot be trusted is like saying no one should have believed Eratosthenes' ( 276 BC - 194 BC ) calculations regarding the circumference because the Magellanic Voyage would not taken place for almost anoth 1,500 years.

    Quite simply, even though seeing is believeing and believing is seeing, understanding allows us to believe that which cannot be seen.

  14. 30 Climate Lessons I Learned in 30 Years

    RedBaron @17

    Thanks for the links.  Part 1 says that it works.  Parts 2 and 3 describe how.  There don't seem to be dramatic differences as in no-tilling with conservation agriculture.  The biggest difference to my untutored eye was the emphasis on not flooding the rice fields during the critical period, but just keeping the plants moist.

    I conclude that there are all these vastly better methods of farming, they would be a considerable help in mitigating climate change, they are being implemented in a small way in various countries, but that wholesale change to these methods is not a priority.

    P.S.  Use of the word "singularly" in the videos is wrong; it should be "singly".  I also can't stand the background music, but I suppose my saying so will just earn me strange looks!

  15. 2017 SkS Weekly Climate Change & Global Warming Digest #36

    I see that Irma missed Mar-a-Lago.  Damn!

  16. Climate's changed before

    If I may beg JH's indulgence for a moment, to make a general point about both the Little Ice Age and the MWP issue :-

    I hope that readers [including NorrisM] can see, in total Holocene perspective, that the LIA & MWP (if discernible at all) are very tiny ripples in global temperature compared with the huge rise which is AGW.    And that neither MWP and/or LIA supply any valid argument against the size/severity & anthropogenic causation of the recent global warming. 

  17. Denying Hurricane Harvey’s climate links only worsens future suffering

    From the last paragraph in the article

     With urban sprawl and poor planning came expansive impervious surfaces – absorbent soil covered instead by concrete and asphalt, increasing flood risks.

    just a note - Houston's soil is a black clay - which is not very absorbent

    Moderator Response:

    [JH] No reference equals sloganeering. Ditto for the assertion, "not very absorbent." 

    Please document the source of your statement about the Houston soil.

  18. 2017 SkS Weekly Climate Change & Global Warming News Roundup #36

    David Roberts, at Vox, always has very thoughtful articles, and his "As hurricanes and wildfires rage, US climate politics enters the realm of farce" continues that trend.  Here he notes what is now a profound 'tribal epistomology' that surrounds American conservatives and insulates them from the conclusions of climate science, among other fact-based conclusions about the world we inhabit.  Some years ago, I became alarmed to find a website called 'Conservapedia', i.e. Wikipedia for Conservatives, which attempts to explain everything Wikipedia explains in a manner consistent with conservative principles.  Check out its main page, and the second most-viewed entry is on 'The Second Law of Thermodynamics', which as you might expect, ends up supporting the idea of intelligent design.

    Roberts: "I look forward to the glorious day when our confidence in the basics of climate science finally makes it from 97 percent to 100 percent. But I think we have reached a point where we can say conclusively that the substantive scientific case for climate change is not going to pierce the conservative bubble, no matter how sharp the spear.

    Hurricanes are battering our shores, the West is on fire, that poor 2 percent of remaining scientific skeptics has been refuted, and here’s Rush Limbaugh, telling people in Miami not to believe meteorologists...

    conservatives will tend to believe on climate change whatever people on Fox (or talk radio) tell them about climate change.

    It is conservative elites, and only conservative elites, who have the power to end this surreal farce. Judging from Rush Limbaugh’s take on hurricanes, they do not yet feel any pressure to do so."

  19. Climate's changed before

    NorrisM & Michael Sweet:

    Please take any further discussion of the Medieval Warm Period to the thread of the SkS Rebuttal aricle, How does the Medieval Warm Period compare to current global temperatures?

  20. New study finds that climate change costs will hit Trump country hardest

    "Scaddenp, that applies to conventional geothermal. Enhanced geothermal is different."

    I dont really follow that. When teasing this out a while ago, I found it partly related to how "primary energy" was defined in a geothermal context (the issue with boundaries), but its mostly due to the relatively low main steam temperature. The inescapable limit of a heat engine. I dont see how enhanced geothermal fixes that?? In most cases getting a higher temperature would mean much more expensive drilling. Enhanced systems also need to account for the pumping energy cost.

  21. New study finds that climate change costs will hit Trump country hardest

    NorrisM - sks basically insist that you comment on the appropriate thread and stick to that topic. Comment here have already veered very far the topic of this thread. Regular here read Sks by using the Recent Comment links so changing to a different topic is not a problem. If you like you can comment on the appropriate place and then put a link to that comment here.

  22. 2017 SkS Weekly Climate Change & Global Warming Digest #36

    Cutting flood protection measures is crazy, incomprehensible stuff, especially given climate change impacts.

    America has huge issues with hurricanes, so even without climate change it beggars belief why you would cut something like that. Americas economy is doing well enough to afford such measures, as gdp growth has been pretty good for several years now.

    Its poor quality, false economy,  short term thinking pandering to business interests, and thumbing their nose at environmentalism. What other concusion can we draw?

    Political leaders need to think long term. They are chairman of the board effectively. We need to adopt the UN development goals, and this provides a framework for better quality short term decisions.

    It's not just hurriciane irma that set a record for sustained wind speeds. Typhoon Hayan set the previous record in 2013. These are both in very hot years globally and climate models predict more intense hurricanes as climate warms.

    Granted studies of past hurricanes have mixed results on intensity partly as records of past intensity arent that reliable , but I doubt its coincidence that two records have been set in a period of high and increasing global temperatures.

    www.accuweather.com/en/weather-news/hurricane-irma-batters-florida-with-catastrophic-storm-surge-wind-and-rain/70002657

  23. Climate's changed before

    NorrisM @554,

    You sepcifically ask about the reference made in a comment on another thread which concerned data from Kemp et al (2011) and a Sea Level reconstruction used to make a comparison with the good-old hockey stick. The actual graphic shown was::-

    Kemp et al reconstruction

    The fit with the hockey stick only works back to AD1000. Simplistically, the SLR found by Kemp et al is saying that (if the SLR is the result of global temperature changes) the temperature was in balance with sea level up to AD1000 after which average global temperatures rose by about 0.15ºC, a level maintained for a period of 400 years, then dropped back for a period of 500 years, after which we have the instrument record showing a global rise of 0.5ºC to 1950 and a similar rise since. So any MWP & LIA are globally very tiny features relative to post-AD1900 warming.

    An alternative is that globally temperature was much flatter with the SLR resulting from regional temperature variation in places that SLR would be sensitive to; places like Greenland perhaps.

  24. CERN CLOUD experiment proved cosmic rays are causing global warming

    Patrick K @21,
    Your specific questions (and also your comments about the galaxy) raise some subjects that are complex and so not yet entirely resolved by science. However it is straightforward to answer your last two questions (2) that cosmic rays are indeed not the only route to forming aerosols, and (3) if there were no aerosols their absence would have fundamental impacts on climate. You would still get ground condensation and presumably any supersaturated atmosphere would still form clouds but at much greater altitudes. Globally that would be a recipe for a run-away greenhouse effect.


    That leaves your first question which is perhaps better framed by asking "How important are cosmic rays in cloud formation?" Svensmark's work is entirely unreliable on this matter, but that is not because he fundamentally misrepresents the motion of the solar system through the galaxy.

    The present structure of the outer Milky Way is now understood but there is still scientific debate over the dynamics of galactic arms. Yet there are surely no theories that don't included the sun moving between arms of the galaxy, this on a scale of ~100 million years/arm. One problem for the likes of Svensmark is that the arms are not neatly positioned (as described by Overholt et al (2009) featured in the OP shows).
    Yet Svensmark (2012)'s calculated Super Nova rates (see his Fig 6) somehow still manage to provide a pretty strong rhythmical pattern.


    At present the sun is also is moving away perpendicular to the disc of the galaxy and this is part of an oscillation which sees the sun returning through the disc every 35million years or so.
    Svensmark seems to ignore this ~35Ma oscillation. Not so Shaviv, one of his co-presenters in "Mystery of Clouds." The work of Shaviv et al (2014) "yields a prominent 32 Ma oscillation with a secondary 175 Ma frequency modulation. The periodicities and phases of these oscillations are consistent with parameters postulated for the vertical motion of the solar system across the galactic plane, modulated by the radial epicyclic motion." Shaviv et al do not then make a 'Svensmark leap' and so do not insist this finding proves a cosmic ray effect. And quite right too, especially for the 175Ma finding.
    Of course, all this palaeo-climate stuff will not directly impact the climate variability of the last few decades. Yet if we assume the mechanism is resulting from cosmic rays and if you can assess the size of the palaeo-cosmic ray wobbles, it could potentially suggest a size for any decadal cosmic ray effect today. Such a step does not appear to have been made of late, even speculatively. If it were, it would be remain highly controversial.


    As for the work at CERN, it provides a more direct but still complicated method of assessment for the impact of cosmic rays.
    But we can have a bit of fun assessings the bold assertions of Svensmark and that is a much easier task. If cosmic rays are a big, big driver of climate and responsible for the warming of recent decades, we should be able to see some form of correlation between temperature and cosmic rays over the last decade. So does this SkS post which is showing data up to 2012 support Sensmark?

    Recently, the level of cosmic rays has been very high of late (this web-page provides the latest data) and these recent high level of cosmic rays should have been peppering the sky with clouds and so should be giving us a big big drop in global temperature. Thus it is a bit of a mystery that we actually find "sorchyissimo!!" with the last four years in turn the warmest on record and this year set is to find a place in the top three.

  25. Climate's changed before

    Norrism,

    This is the graph for the Northern Hemisphere from Mann et al 2008 :

    There might be a more recent paper that I did not find.  Mann has done the analysis with no tree ring data and it is the same as with the tree ring data.

    It is usually possible to get free copies of papers if you Google them (I found this paper using Google). Apparently it is only for the Northern Hemisphere (as was the other graph I posted). More data is available for the Northern Hemisphere so Mann only did the Northern Hemisphere in 1998.

    Here is a global analysis by Marcott et al  (SkS article about Marcott)

    marcott in red

    Marcott is the red line.  The small bump up is around 1000 years ago and is too early for the MWP.  Current temperature is about 1.0 on this graph.

    Keep in mind that we expect the temperature to decline after the Holocine maximum to a new ice age.  This is the decline from 5000 bp to 150 bp.  AGW then kicks in in earnest.  AGW might have slowed the decline in temperature from 5000bp on from early farming releasing CO2.

    I see no indication of a MWP in any of this data.

  26. New study finds that climate change costs will hit Trump country hardest

    michael sweet,scaddenp and MA Rodger

    I have now read both the Weissbach and Ferroni papers and the responses by Raugei et al as well as one rebuttal by Weissbach.  It gets costly paying for some of these downloads so I have had to restrict myself.

    Would you prefer me to provide my thoughts on the michael sweet SkS article referenced above?  I am still wading through the IPCC 2014 report on costs but the EROI is an interesting place to start.

  27. Climate's changed before

    Moderator

    Thanks, I have now read your Policy Statement.  I would have thought that my references to nigelj's comments re ocean temperatures (on another stream) somewhat corresponding to the periods "alleged" to be the MWP and the Little Ice Age would be considered  "additional information" and not just repetition of earlier positions.  Surely a matching of ocean temperatures tells you something about atmospheric temperatures at the same time.

    Furthermore, my reference to the recent Chinese Academy of Science recent paper analyzing temperatures over the last 1,000 years in China was also something which shows that this was not just a period isolated to parts of the Northern Hemisphere.  Does anyone have any comment on this?  I have read somewhere else (and I do not have a citation) that during the MWP the tree line of the Rocky Mountains was much higher than at other times.  This would just about "connect the dots" for all of the Northern Hemisphere since we have Northern Europe, Greenland, Newfoundland and China already.

    The above graph has posted the Michael Mann 1998 hockey stick.  My understanding is that sometime around 2007 he revised his graph.  Could someone post his most recent one?  For some reason, I thought it was not so "flat".  Perhaps because it does reach back further than 1400 to cover the period from 800 AD.  If this is totally "out of the blue" with reference to the Rocky Mountain treeline,  I will find my source for this statement or acknowledge that I cannot find it.  However, my guess is that you have heard this before.

    I will again reiterate that even if there was an MWP, it does not prove anything about today's temperatures but only goes to show that this has occurred before when it was not caused by man.

    Moderator Response:

    [JH] Please provide a link to the Chinese Academy of Science paper that you have cited.

  28. Climate's changed before

    Eclectic,

    Bob Loblaw's comments are always thoughtful.

    Your understanding of the MWP and mine are much the same.  There were various warm and cold periods worldwide but they were not all at the same time.

    According to Mann's Hocky Stick from this SkS reference:

    Hockey Stick

    Where is the drop in temperature for the LIA?  I do not see any noticable drop between 1600 and 1900.  There is an overall drop over the entire graph (the Hockey handle) that is probably the descent into the next Ice Age that was stopped by CO2 emissions.  As you would expect, there is some noise.

    Since I see no special "LIA" I conclude that it never existed.

    I see that the above graph confirms Mann's original Hockey stick as very close to the best data available ten years later. 

  29. Climate's changed before

    Eclectic:

    Another weakness of the "recovery from the Little Ice Age" meme is that the Little Ice Age ended a long time ago (in weather terms). Such a "recovery" should be fast in the early stages, and proceed more slowly as it appraoches the state it is recovering to. It wil not, without some magical physics, proceed slowly at first and continue to "recover" at faster and faster rates later on. If the current warming is "recovery from the Little Ice Age", why didn't it recover two hundred years ago?

    Tha magical physics of the "Recovery" meme requires that whatever caused the Little Ice Age must proceed very quickly to create the Little Ice Age, but removing tha cause must proceed very slowly to get us back out of the Little Ice Age.

    Such physics is not impossible - c.f., adding CO2 to the atmosphere by burning fossil fuels causes a rapid rise, whereas the atmospheric CO2 will not drop rapidly if we stop burning fossil fuels. We have a good physical explanation for that behaviour, though. The "recovery from the Little Ice Age" meme has no such physcial explanation, however, as you point out.

  30. Climate's changed before

    Michael @557 ,

    please correct me if I have gained the wrong impression : that impression being --

    (A) There was no global MWP, as the numerous "warm patches" of approximately 1,000 years ago were Northern Hemispheric and were minor and not contemporary.  In other words, the so-called MWP is nowadays a Eurocentric "beat-up" from denialists who are using outdated ideas and who are being very economical with the truth.

    (B) The so-called Little Ice Age actually "was a thing" : as it involved some cooling of both hemispheres (IIRC, caused by two Solar Grand Minima, helped along by a number of above-average volcanic eruptions).   Also IIRC : the Little Ice Age was a rather minor affair, constituting a global temperature drop of only about 0.3 or 0.4 degrees below the natural long-term (multi-millennial) slow decline of global temperature [until the modern rapid "Hockey Stick" rise caused by AGW, of course!].

    I often see denialists claim that the temperature rise of the 1800's and 1900's was nothing more than a "rebound effect" from the LIA.  That argument seems [to me] to be a complete nonsense, since recent temperatures are higher than the extrapolated pre-LIA levels (and the Holocene temperature is on a natural down-curve).  And those denialists are supposing that any changes in global climate simply occur for no physical reason.  Perhaps they subconsciously think of global climate as being a sort of inner-spring mattress!

  31. One Planet Only Forever at 23:41 PM on 10 September 2017
    Denying Hurricane Harvey’s climate links only worsens future suffering

    nigelj@35,

    You are correct. I am "Excessively-Reacting" to NorrisM's use of the term Warmist to refer to the scientific concensus side of the debate he believes is "Inevitable" and could be "Helpful".

    This started on the comment string of "The Trump administration wants to bail out failed contrarian climate scientists".

    I am emphasizing the understanding that the two sides of any discussion regarding the well developed and robustly defendable understandings of climate science -> global warming -> climate change must be understood to be "The well developed and robustly defendable understandings" which can be called the "Scientific consensus on the matter" but not a term open to interpretation such as "Warmists".

    Of course, that means that 'Everyone genuinely interested in developing and delivering New Evidence to improve/increase the awareness and understanding is part of the Consenses team' as long as they are producing robustly defendable new information/understanding.

    Everyone else is on the Other Side. and all the other side has are questions that can be answered and criticisms that can be debunked. And everyone who is still trying to do that after all these decades of opoortunity to be more aware and better understand this issue deserve to be called Denier/Delayers. And that means the matter is Undebateable. Questions can be asked and answered. And attempts to change the understanding that are not robust get debunked. And the public gets the questions along with the answers, the weak claims with their debunking, from every information source that ever delivered climate related statements.

    And it is the contunued effort to drum up unjustified popular support for 'beliefs' contrary to the developed better understanding for climate science that has kept Leaders who consider themselves 'beholden to popularity rather than responsible to inform and correct misundertstandings' to fail to Lead the improvement of protection of the general popultion from the more difficult to accurately predict but most likely to be increasing risks of harm being created by rapid climate change due to rapid global warming due to massive global impacts from humanactiovity that is ultimately unsustainable and has aletrnative (though admittedly more expensive that getting away with the unsustianbel damaging activities for as long as can 'Popularly' be gotten away with, especially when people perceived to be Winners can succeeed through actions that promote the unjustified and damaging popularity)

  32. Climate's changed before

    NorrisM,

    For this instance, the data very clearly shows that there was not a global MWP or little ice age.  Since they never existed, they cannot be denied and your comment using the word denied appears to be deliberately offensive.  

    You have previously made statements about the MWP and LIA and have been referred to citations that show they were local events and the global temperature is shown by the Hockey Stick of Mann et.al.  Since you have been shown data to support Mann et al and have provided no data (because it does not exist) to support your claim Mann was incorrect you are sloganeering by repeating an unsupported claim.

    Many scientists have reproduced Mann's Hocky Stick using a variety of methods and data.  It is completely accepted by anyone informed about AGW.  Use the search button to find SkS references to educate yourself. If you have a question we are happy to help you understand, but claiming Mann is incorrect repeatedly makes it appear that you are not reading (or reading and ignoring) the answers people give you.

  33. Animals and plants can adapt

    guad,

     You are factually incorrect. An appeal to nature is an argument or rhetorical tactic in which it is proposed that "a thing is good because it is 'natural', or bad because it is 'unnatural'".

    Whereas this article focuses on actual things that are bad...because they would be bad whether natural or not. Ecosystems have functions. We call this ecosystem services. You might want to read up on it, since it is what keeps you alive. Ecosystem services

  34. 30 Climate Lessons I Learned in 30 Years

    Digby Scorgie,

    Here is a primer 101 on SRI

    SRI English Pt 1 of 3 System for Rice Intensification
    by Dana Hemingway

    SRI English Part 2 of 3 System of Rice Intensification
    by Dana Hemingway

    SRI English Part 3 of 3 System of Rice Intensification
    by Dana Hemingway

  35. Other planets are warming

    It’s also worth noting that it takes about 240 million years for the Sun to complete one orbit around the centre of our galaxy, a period sometimes referred to as a cosmic year. One cosmic year ago the Earth was just recovering from the worst mass-extinction ever, the end-Permian 252 million years ago. It should be unnecessary to say that any significant climate changes related to the galaxy (if there are any) happens on a much, much larger time scale than a century or so!

  36. 30 Climate Lessons I Learned in 30 Years

    RedBaron @15

    Ah, I see what you mean about matching farming method with corresponding biome.

    I had a look at the article about rice.  It lists all the advantages, but doesn't say how it differs from traditional methods.  How does it?

  37. Study: mild floods are declining, but intense floods are on the rise

    If the intensity of rainfall events is indeed increasing, it becomes even more vital to adopt the farming techniques described in David R Montgomery's book, Growing a Revolution.  Also valuable is to encourage the spread of beavers in all our catchments.  Both not only reduce flood peaks but increase flows during low water.  Beavers replace the function of glaciers in storing water during high winter precipitation and releasing water during the growing season.

    http://mtkass.blogspot.co.nz/2007/07/canadian-beaver-pest-or-benefactor.html

  38. Other planets are warming

    Jonplumb @46 ,

    Lest you think that Daniel's reply is giving you the "brusque off" . . . let me expand the answer to your humorous question [though to be more precise, your question is more like 3 jocular assertions, well beyond science fiction comedy].

    Since our solar system is roughly 25,000 light years from the galactic center, then our solar system would need to travel around 20,000 light years to get into the more densely-starred inner regions, where, let us suppose [though it isn't] the background radiation level is the equivalent of 1 degree hotter (i.e. the 1 degree hotter that the Earth's surface temperature has risen, in the past 150 years or so).

    The hypothetical rubber-band pulling our solar system (toward the inner Galaxy) would need to be extraordinarily strong — also, if you care to calculate the accelerations involved, they turn out to be truly formidable.   And there is the (relatively small) problem that the solar system would need to travel at well over 100 times the speed of light. [Fortunately, Einstein is long dead, and so won't be able to protest against that "Alternative Fact".]

    Then there is the minor difficulty: umpteen thousand professional and amateur astronomers (as well as a few billion non-astronomer humans) have not detected any significant displacement of Earth relative to the stars visible at nighttime, during the past century or so.  Though conceivably that may all be a ginormous Conspiracy cover-up (a conspiracy in which your own eyes are also participating!  Damn your lying eyes!).

    All that aside — and assuming that (despite appearances) we are now really close to the galactic center, and this position (somehow) caused recent rapid global warming — there is still the problem of CO2.  Since the fossil-fuel CO2 in the atmosphere does (scientifically) nicely explain the recent 1 degree temperature rise . . . then we must (somehow) discover some totally unexpected and new factor (a cooling factor) which nicely cancels out the 1 degree of AGW.

    So, overall, the "rubber-band" oscillation of our solar system within the galaxy . . . is an "explanation" which is trying to push a megaton of sewage uphill with a pointed stick (of toothpick size).

    BTW, Jonplumb, the true center of the galaxy is not "fiery" but actually a Black Hole — the very opposite of "fiery".   Let's just hope that the supposed Galactic Rubber Band is not slingshotting our whole solar system right into the Black Hole!  That would be a grave situation — indeed, a situation of extreme gravity!

  39. CERN CLOUD experiment proved cosmic rays are causing global warming

    Hi there, this is my first post to your site and is more of a question than a comment.

    I recently had the misfortune of watching the documentary "The Cloud Mystery" which presented Henrik Svensmark's Cosmic Ray Theory (CRT) as being the driving force for climate change. The documentary did not appear to be solid science to me which is why i was surpised CERN appeared to be reasearching CRT for climate change.  Aside from the documentary's lack of defining or explaining scientific terms, and, misrepresentation of the fundementals Geology and Atronomy, i.e., our solar system does not move to different arms of our galaxy as we orbit the galactic center, the documentary really didn't adress a basic question. Do we need cosmic rays to create aerosols for cloulds to form? Are cosmic rays the only way to get aerosols in the astmosphere? Is there or was there ever a shortage of aerosols in our atmosphere that prevented cloud formation thus making our asmosphere supersaturated with water vapor that couldn't condense? This is just my cursory look at the CRT for climate change, but it appears to me that the CRT may be a solution to a problem that doesn't exist.

  40. Animals and plants can adapt

    This is appeal to nature fallacy. Just because some species exist, doesnt mean it's necessarily good that they continue to exist. Also, "animals/plants can adapt" doesnt necessarily mean every specie will adapt. it means life in general will adapt and create new forms of animals who, guess what, can now survive in the new climate. Throughout history catastrophic events changed entire climate of the planet in a day. and yet life survived, and flourished. So this entire appeal to nature fallacy is wholly uninteresting to me.

  41. New research, August 21-27, 2017

    Thank you for this list. Will try to digest
    whatever lists you post whenever, whereever.
    As a normal worker, I have no chance to keep up,
    otherwise.

  42. 2017 SkS Weekly Climate Change & Global Warming News Roundup #36

    The "6 questions on hurricanes irma etc" link doesn't work. I tracked down the article using google as below.

    insideclimatenews.org/news/06092017/hurricane-irma-harvey-climate-change-warm-atlantic-ocean-questions

    Moderator Response:

    [JH] Link fixed. Thank you for bringing this to our attention.

  43. Other planets are warming

    No.

  44. Denying Hurricane Harvey’s climate links only worsens future suffering

    One Planet Only @34

    I think you are technically correct about the term warmist and what it implies, and context etc. Shrewd observation.

    I also find the term demeaning and very annoying, and its intended to be demeaning like the term "liberal elite" or "too pc".

    But most people wont have any idea what you are getting at (average IQ is 100) They will just see you as being petty and over complicating things.  

    It's a term I hate, but accept in good humour. Instead I would say "yes Im a warmist because thats where the evidence points". Dont let them "bait you" with label, move right on past it and swivel discussion right back to the facts and evidence.

  45. Other planets are warming

    I've found this thread very intriguing (and long-running). I just wanted to ask a question related to all of this:

    First, I recently read a theory that our solar system might be weaving in and out of our galaxy, moving over time closer to the galactic center and rubber-banding out to the outer rim, repeatedly. Would this not be cause enough for global warming? It would surely explain the supposed temperature increases on other celestial objects (while understanding that some objects could still cool to lower temperatures simply because of its phase in its lifecycle). Even with the sun reducing its output, the general increase in temperature as we approach our fiery galactic center could easily counter the decrease in output by the sun. Also, if the cosmic dust cloud we're traveling through were to get any thicker, even by a small fraction, would that not also "trap" the sun's heat increasing the temperature of our solar system?

    I'm just curious if our temperature changes might be related to the position of our solar system withon the galaxy, just as seasons temperatures can change based on our position around our sun. 

    Thoughts?

  46. Climate's changed before

    Moderator.  I would be happy to avoid "sloganeering" if I knew what it was.  I was not using slogans in the part snipped above.  Can you define this term?  You have my email address.  I would be happy to have the definition offline.  There are numerous contributors to this website who present political comment who are not chastised when they make reference to matters which are not factual based.  For example, the discussion of who is and who is not a "denier" and what various subsets there should be of this classification.  Have requested a definition of "sloganeering" before.  Could you provide one?  Thanks

    Moderator Response:

    [JH] "Sloganeering" is explicitly defined in the SKS Comments Policy. You have been advised more than once to read the Comments Policy and to adhere to it.

  47. Climate's changed before

    NorrisM:

    I am not a moderator here, but I've been around a while. In my interpretation, "sloganeering" is the repeated posting of unsupported assertions, covering the same material, while ignoring comments that have pointed out information that contradicts the assertions.

    You appear to be simply ignoring a lot of comments. SkS also has a rule against "dog-piling", where one commenter is facing comments from a large number of opponents. Regulars here do try to avoid that by restricting comments, but you can help by selected a very small number of posts to comment on, and sticking to those issues until more-or-less resolved, before going on to other topics.

    Moderator Response:

    [JH] "Sloganeering" is explicitly defined in the SKS Comments Policy

  48. Climate's changed before

    nijelj

    In looking for something else, I just saw this reply of yours on one of the blogs:

    "Your understanding or information is wrong. Sea level rose from AD800 to around 1500 then fell until about 1900, then started rising as in the link below. This correlates reasonably well with burning of fossil fuels so all or nearly all this sea level rise can be attributed to fossil fuels."

    Just curious but does this sea level rise and drop pre 1900 correlate quite well with the theory of the MWP and the Little Ice Age?

    We now have the Chinese study which also seems to support both the MWP and Little Ice Age.  If you need I cite for the Chinese study I can get it for you.

    Again this does not prove anything about the existing warming but the denial of the MWP and the Little Ice Age is part of the "Hockeystick" theory suggesting that this present warming is anomalous over the last 2000 years.

    Moderator Response:

    [JH] Sloganeering snipped.

    Please note that posting comments here at SkS is a privilege, not a right.  This privilege can and will be rescinded if the posting individual continues to treat adherence to the Comments Policy as optional, rather than the mandatory condition of participating in this online forum.

    Moderating this site is a tiresome chore, particularly when commentators repeatedly submit offensive, off-topic posts or intentionally misleading comments and graphics or simply make things up. We really appreciate people's cooperation in abiding by the Comments Policy, which is largely responsible for the quality of this site.
     
    Finally, please understand that moderation policies are not open for discussion.  If you find yourself incapable of abiding by these common set of rules that everyone else observes, then a change of venues is in the offing.

    Please take the time to review the policy and ensure future comments are in full compliance with it.  Thanks for your understanding and compliance in this matter, as no further warnings shall be given.

  49. One Planet Only Forever at 02:30 AM on 10 September 2017
    Denying Hurricane Harvey’s climate links only worsens future suffering

    nigelj@23,

    I am still sorting out thoughts to try to be brief yet clear.

    The term/label Warmist, without clear context, is not a good term to use by itself.

    Climate science has robustly established Good Reasoned Explanations based on all the available evidence.

    Therefore, people who want to claim that the amount of warming due to increased CO2 is less than the established understanding without actually providing significant robust new information or explanations are a sub-set of the Denier/Delayer group.

    Some people are referring to those type of made-up claim-makers as Warmists (including those type of people referring to themselves that way). But such a label needs to be clearly understood to be a sub-set of the Denier/delayer group. Using Warmist to refer to people who aren't honestly legitimately contributing to increased awareness and better understanding may shed an undeserved 'positive light' on what they are trying to get away with, or may annoy people who think that an 'ist' label like Warm-ist is undeservingly dismissive.

    NorrisM referring to the scientific consensus group as "Warmists" could easily be interpretted as a denigration of the science consensus group (and his use of that term that way is the main focus of my commenting). His other comments appear to be attempts to be dismissive of, or argue unjustifiably against, the scientific consensus and the resulting required changes of human activity (basically trying to argue against part of the Sustainable Develop Goals without justification) rather than contribute to increased awareness and better understanding.

    My point is that the consensus understanding regarding climate science issues are 'robustly defendable for what they are'. It would be clearer if all claim-making that does not have a robust significant 'new understanding' basis, or persistent questioning contrary to that understanding (a failure to learn from the responses to questions asked) was always referred to as the actions of a Denier/Delayer or a sub-group, not just "Warmists".

    NorrisM's use of Warmist for the Climate Science Consensus group could be seen as 'legitimate by someone having unjust reasons for preferring to believe things that are contrary to the developed best understanding (a Denier/Delayer)'. And 'someone having unjust reasons for preferring to believe things that are contrary to the developed best understanding (a Denier/Delayer)' could see the use of the term Warmist by people trying to support the consensus understanding as an undeserved denigration of what the Denier/Delayers would prefer to believe.

    Perception can lead to 'Belief'. And 'Belief' can clearly be contrary to independently confirmable understanding (Reality).

  50. Study: mild floods are declining, but intense floods are on the rise

    Hi

    The premise explained beginning of this post is incorrect. Although you explained  some limitations, you missed the most important limitation being; understanding of the geology of the highly porous and high transmissivity of the Holocene recent and the hydrological dynamics of the cover and basement.

    In addition, the comments introducing the topic constitute alarmist rhetoric. Shameterism at best. I suppose that's what you get with suspicious journals and the quality of their peers!

    The NH is warming in places and the SH seems to be cooling despite slowly climing CO2. There is actually more evidence for a cooling SH than a warming simply because our macro observations cannot be fudged in the same way the data is been!

    Moderator Response:

    [JH] Nonsensical and inflamatory sloganeering snipped. 

    Please note that posting comments here at SkS is a privilege, not a right.  This privilege can be rescinded if the posting individual treats adherence to the Comments Policy as optional, rather than the mandatory condition of participating in this online forum.

    Please take the time to review the policy and ensure future comments are in full compliance with it.  Thanks for your understanding and compliance in this matter.

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