Climate Science Glossary

Term Lookup

Enter a term in the search box to find its definition.

Settings

Use the controls in the far right panel to increase or decrease the number of terms automatically displayed (or to completely turn that feature off).

Term Lookup

Settings


All IPCC definitions taken from Climate Change 2007: The Physical Science Basis. Working Group I Contribution to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change, Annex I, Glossary, pp. 941-954. Cambridge University Press.

Home Arguments Software Resources Comments The Consensus Project Translations About Support

Bluesky Facebook LinkedIn Mastodon MeWe

Twitter YouTube RSS Posts RSS Comments Email Subscribe


Climate's changed before
It's the sun
It's not bad
There is no consensus
It's cooling
Models are unreliable
Temp record is unreliable
Animals and plants can adapt
It hasn't warmed since 1998
Antarctica is gaining ice
View All Arguments...



Username
Password
New? Register here
Forgot your password?

Latest Posts

Archives

Recent Comments

Prev  507  508  509  510  511  512  513  514  515  516  517  518  519  520  521  522  Next

Comments 25701 to 25750:

  1. Record hot 2015 gave us a glimpse at the future of global warming

    Steve L @2&3, calculating the trends for La Nina, Neutral and El Nino years seperately on the BEST LOTI (Sea Ice as Air Temperature) since 1966, it turns out that 2015 will be the average temperature for an El Nino year in 2018, for a neutral year in 2023 and for a La Nina year 2028.  The precise year estimated will depend on the temperature set used, and the ENSO index used (I just used the classification in Dana's graph below).

    That means that within three years, we can expect the average El Nino to match 2015 temperatures, with El Nino's occuring every three to four years on average.  Put another way, by 2028 we can expect to have experienced five or so years approximately as hot as 2015, and likely one or two hotter.

  2. Record hot 2015 gave us a glimpse at the future of global warming

    Dana, in the extended section of the OP, it is claimed that El Nino, neutral and La Nina years all have the same trend of 0.16 C per decade.  That claim is belied by the graph, however, were the slope of the trend line for neutral years is visibly less than that of El Nino and La Nina years, and where pixel count shows the trend lines for El Nino and La Nina years draw apart, showing the El Nino trend to be greater than the La Nina Trend.  Could you note the exact values.

  3. Record hot 2015 gave us a glimpse at the future of global warming

    Ah, I see by following the link to the Guardian, Trenberth indicates it would be 15 years before we could expect to frequently see anomalies such as observed in 2015.

  4. Record hot 2015 gave us a glimpse at the future of global warming

    I like the quote at the end from Trenberth.  Perhaps the best way to communicate this result, besides saying it's really warm and this warmth is having big negative consequences, is to predict when this global surface anomaly will become "normal".  That is, how many years is this year's anomaly ahead of the long-term trend (say, 1970-2014 ... don't want to cherry-pick a biased end date).  At about 0.15 C increase per decade, and 2015 being about 0.14 C warmer than 2010 and 2014 (with 2014 being approximately on the trendline?), then we should expect 2015 temperatures to be "normal" by about 2025.

    Is this correct?  On average we should expect to see years like 2014-2016 by 2024-2026?  I think this also says that it would be abnormal to see another year so warm before then, and it would be really weird to see several more than one of them.  Perhaps this kind of messaging to the media would help to avoid wasteful discussion of a new hiatus in the next decade.

  5. A Rough Guide to Rainfall, Run-off and Rivers

    Read "Three Against the Wilderness" by Eric Collier; especially toward the end when he describes the flood of 1948 in the Frazer River catchment. This flood descimated the Frazer delta, raising water levels to the first and sometimes the second floor of houses on the delta.  It was caused by a huge snow pack and a very late spring that when it happened came on rapidly went straight into summer.  The only creek along the Frazer Valley that didn't contribute to this flood was Meldrum Creek.  Eric had, along with a very forward looking conservation officer, R.M. Robertson, reintroduced the beaver to the catchment some years earlier and they multiplied and restored the environment and with it, it's water storing capacity.  If beavers has been spread throughout the Frazer catchment, the flood never would have happened.

  6. Record hot 2015 gave us a glimpse at the future of global warming

    So because of this El Nino created jump in the temperature,we can expect another "hiatus" starting in 2017.  The climate change deniers can have fun with this one.  They can now start their graphs in 2015 and at least for a few years explain to us how the climate is cooling.  That is, unless we have passed one or more of the tipping points and 2017 turns out to be warmer than 2016.  

  7. Wigley and Santer Find the IPCC is too Conservative on AGW

    Jsalch @27, the principles used in climate models are not assumptions.  Climate models are reiterative calculations of causal relationships relevant to global climate.  Thus one part of a model will handle conservation of momentum, requireing that momentum be conserved when are masses move from one cell to another in a model.  Another will handle the effects of Boyle's law with regard to vertical motion of gas under convection.  Another part again will handle radiative absorption and emission.  All of these causal laws that go into a climate model are very well confirmed physical theories from both laboratory and non-laboratory observations.  

    There is a problem in that the smallest practical resolution of climate models is much larger the resolution of laws applied.  Consequently to make the physics work, parameters need to be introduced to handle the approximation.  These parameters, however, are justified in detail based on the causal laws - and refined by comparison with real world observations.

    The range of physical laws, and hence causal relationships embodied in GCMs ranges through radiative physics, newtonian dynamics, gas laws, laws of evaporation, and on into laws of chemistry.

    The output of the models are then tested against both much simpler models and against global observations of a very large number of variables (not just Global Mean Surface Temperature).  All GCM's produce earthlike climates with an astonishing verrisimilitude - which is astounding given the number of physical laws embodied in their operation, and the courseness of their grid.  Combined they also produce quite accurate predictions of physical values in absolute terms.  They are made to look like the perform much worse than they do because values are expressed in relative terms because doing so highlights discrepancies - the better to be able to test and improve the models.

    When you summarize this process as "if [assumptions from climatology models], then humans are the problem", it merely demonstrates your complete ignorance on how climate is actually modelled in GCMs.

    Curiously, however, there is one class of 'scientist' who only ever present simple, statistical models of climate - ie, whose output could be described as "if assumptions, then results".  That class are the AGW deniers.  They are so confident in their theories that they never dare model them based on detailed representations of physical law.  

  8. Wigley and Santer Find the IPCC is too Conservative on AGW

    Jsalch, basic physics was used to project human-caused warming many decades before it was possible to observe it. See the post How Do We Know More CO2 Is Causing Warming? Also read The History of Climate Science, and for details Spencer Weart's The Discovery of Global Warming. Watch Pierrehumbert's AGU lecture describing successful predictions, or at least read a summary of his talk. And Climate Change Cluedo.

  9. Wigley and Santer Find the IPCC is too Conservative on AGW

    It appears that the whole point of causality versus correlation is skipped.  I am a statistician, not a physicist or chemist.  However, most of these types of paper seem to read ...  "if [assumptions from climatology models], then humans are the problem."

    I'd like to see where causality is addressed.

  10. Thorough, not thoroughly fabricated: The truth about global temperature data

    Cruz is trained as a lawyer - his job is to advocate for his client, without regard for the truth.  If he gets a murderer acquitted, he has done his job regardless of whether the suspect was actually guilty or not.  Sometimes lawyers don't do well in a field like science, where the goal is to find out the truth, regardless of any potential impacts it may have.

    I find it amusing when deniers insist that the raw data are more accurate than the corrected data, while also insisting that raw data are inaccurate and must be adjusted for urban heat island effect, poor station siting, and other factors that might conceivably raise the temperature.

  11. Thorough, not thoroughly fabricated: The truth about global temperature data

    Scaddenp @ 9 , please . . . do tell the dreadful secret of your cognitive bias ~ unless it involves something actually illegal, of course !

    No, I don't think we can excuz Cruz, on the grounds that no-one else is absolutely perfect.  There are shades of grey in many concepts, to be sure . . . and especially on the spectrum between undoubted sanity and undoubted insanity.  Slightly off-white and almost pitch-black, may well be on the same spectrum ~ but there is a huge qualitative difference, that amounts to a recognizable difference of category.

    Digby's possibility (1) is something that features on a dimension at right angles to the sane/insane spectrum.  And that is: the moral dimension. There we are treading more on the territory of religion & ethics.

    But you could equally argue that "cognitive bias" [ possibility No. 2 ] also has a moral dimension of good/evil, when the bias is extreme.

  12. Thorough, not thoroughly fabricated: The truth about global temperature data

    (2) is simply cognitive bias and frankly I think everyone suffers from it to a certain degree (I do). Fortunately, the scientific method as it has evolved, and when practised as a community gives us a way to break from the biases. Getting someone to accept a proposition that is conflict with their values and/or identity is close to mission impossible.

  13. Thorough, not thoroughly fabricated: The truth about global temperature data

    Glenn

    Is Cruz declining to tell all of the truth or is he just denying the truth?

    There are two possibilities:

    (1) Cruz knows that global warming is a threat.

    (2) Cruz does not want to know that global warming is a threat.

    What do you call someone of the first type — psychopath?

    What do you call someone of the second type — a victim of a special form of insanity?

  14. Thorough, not thoroughly fabricated: The truth about global temperature data

    Scott Johnson, I don't know if you're reading the comments here, but this post is just about the most helpful one I've ever seen at SkS. And that's saying a great deal.

  15. IPCC overestimate temperature rise

    Needs an update for 2015, if anyone has access to do that.

  16. Ted Cruz fact check: which temperature data are the best?

    Thanks Tom for the more detailed info on the lag time between the satellites detecting the heat. Makes sense. It will be interesting to see the RSS data move up as it begins to detect it. Off course we pretty much walk about the surface of the Earth so surface temperature is what we live in not the troposphere 7 -10 klms above us. Thanks for all the info. Best regards MEJ

  17. Ted Cruz fact check: which temperature data are the best?

    MEJ @23 & 24, arguably the largest El Nino since 1950 occurred in 1997/98.  As a result the GISTEMP Land Ocean Temperature Index set a new global temperature record of 0.47 C, a record it broke in the following year with a 0.63 C annual average (both relative to a 1951-1980 baseline).  In contrast, RSS TLT only showed a distinctly non-record 0.1 C, only just shading 1987 and beaten by 1995.  It then went on to a massive 0.55 C in 1998.  (Records relative to a 1979-1998 baseline.)  The reason for the very low temperature in 1997 relative to 1998 was the lag.

    2015 is also arguably the largest El Nino since 1950, although I think it is smaller than 1997/98.  Of course, there is a strong possibility that it will be referred to as the 1015/16 El Nino in the future.  Regardless, the most comparable temperature from the 97/98 El Nino with which to compare the 2015 TLT temperature is 1997, which was not a record year.  Well, at 0.36 C, 2015 isn't a record in the TLT series either, but it is a lot warmer than 1997, and is only beaten by 1998 and the 2010 El Nino year.  Further, the most recent montly temperature (0.54 C) is very comparable to the 1998 annual record (0.55 C) and very close to most months in the 97/98 ENSO period as well.

    So, the reason why 2015 is not a record in the TLT temperature series, while it is a record in the surface temperature series is very clearly the greater lag in response to ENSO events in the mid troposphere.  The leaders of the denialist pushback against the extraordinarly warmth in the surface record for 2015 know this very well.

  18. Ted Cruz fact check: which temperature data are the best?

    Thanks Moderator. I read it till my brain hurts. I read the post and watched the video. Cool to see Dessler and Mears interviewed. I also read the link John Hartz posted above which also included UAH satellite data. Thanks for that John.
    Oh, okay I have not understood SURFACE TEMPERATURE as opposed to Lower Troposphere Temperature (TLT). Two different places. One we don't even live in. That is my mistake. Add in the inaccuracies inherent in satellite data in the video. Also as I presume you are alluding to there was a 'lag time' for the heat from El Nino in 1998 being detected in the TLT by satellite readings.

    Ok got it
    Thanks
    MEJ

  19. Ted Cruz fact check: which temperature data are the best?

    Hi everyone. If I could get some help understanding why the Remote Sensing Systems (RSS) satellite data does not indicate 2015 as the hottest year on record.

    Historical RSS Data Graph

    The graph seems to show quite plainly 1998 as the hottest year and even 2010 as being hotter than 2015.

    If I was to look at this graph I would say (possibly wrongly) 1998 far outsrips 2015 as the hottest year on record.

    Thanks for any help understanding this.

    Regards
    MEJ

    Moderator Response:

    [PS] Um, that is largely what the article is about. Did you read it? 2015 is the hottest surface temperature on record (we dont live in the TLT). I would also watch this space if lag in response to El Nino in troposphere follows previous pattern.

  20. Thorough, not thoroughly fabricated: The truth about global temperature data

    DS

    "Not fully sharing your knowledge and understanding with others can give you a competitive advantage. "

    One of the creative ways to lie

    "Tell the Truth. But Not All Of It"
    Robert Heinlein

    And yeah, Susan Cain's book is awesome.

  21. Thorough, not thoroughly fabricated: The truth about global temperature data

    They are not climate skeptics.  They are climate-change deniers.

  22. It warmed before 1940 when CO2 was low

    @35 - 37 in response to 34

    Thanks for the references and comments. Now I can give a more informed answer to the question.

  23. It warmed before 1940 when CO2 was low

    Kevin C @36, this is the relevant image from the article to which you link:

    The right hand series of panels is ERSST v4-v3b.  In it land temperatures are cancelled out and consequently not shown.  The middle column of panels (ERSSTv4) however, does show land temperatures.  In particular, it shows a very warm Chile plus Argentina, more or less adjacent to the unusually warm south east Pacific temperatures.  Further, checking the 250 km resolution, meteorological station only map for the 44-45 period at Gistemp shows an off shore (island) meteological station of the coast of Namibia or Angola which again shows unusual warmth.  Finally, the west coast of Australia is warm, although not exceptionally so in the 250 km resolution GISTemp map.  These correlations to the warm pools in the SH in that period suggest those warm pools are not, or at least not entirely artifacts.

  24. It warmed before 1940 when CO2 was low

    tcflood: The narrow WWII peak itself is almost certainly spurious. It only shows up in the SST data, and particularly in ERSSTv4. There are very substantial known changes in SST measurement practices during WWII, which are hard to correct for completely. Hansen discusses it here.

  25. One Planet Only Forever at 07:47 AM on 24 January 2016
    Thorough, not thoroughly fabricated: The truth about global temperature data

    nigelj,

    More important points about the Satellite record are:

    • The satellite temperature values do not measure the surface temperature.
    • The result of increased CO2 concentrations is understood to be a more significant warming of the surface, under all the CO2, than the warming that would occur up in the atmosphere.
    • The satellite data may be less reliable than surface temperature data for a number of reasons.

    People like Cruz who try to make claims based on the satellite data are likely to understand the above points. They deliberately do not want to more fully inform others of what they are aware of (typical debate, legal, political and economic tactics)

    Not fully sharing your knowledge and understanding with others can give you a competitive advantage. Especially if scientific investigation for political marketing purposes indicates that a significant portion of the population are willing to be easily impressed by misleading marketing claims or outright lies.

    The power of being able to 'create impressions' began trumping the significance of the 'actual substance' of an issue in the late 1880s (Pointed out by Susan Cain in "Quiet: The Power of Introverts in a World That Can't Stop Talking"). That is obviously something that needs to change (contrary to desires to prolong or expand many developed damaging and unsustainable 'popular profitable pursuits of perceptions of prosperity').

  26. Thorough, not thoroughly fabricated: The truth about global temperature data

    Cruz is either lying, or being misleading. He's intelligent enough to know using 1998 as a start point in the data isn't valid science.

    This is particularly frustrating coming form Cruz, who sets himself up as a strong Christian with impeccable moral values, or at least aspirations to impeccable vales.

    Its time the world stopped making excuses for people like Cruz. They should be utterly condemned for what the way they are acting, like utter charletans. Where's the media holding these people to account? Nobody has the intelligence or courage to do it, apart from a few websites like this one.

    Not all climate sceptics are insidious people obviously, however the world is being held to ransom by a few fanatical climate sceptics. These people are towards the outside of the bell curve in terms of beliefs. Some of them may have some sort of personality disorder.

    The satellite record shows 2015 was the third hottest year, according to UAH. However there is also a delay before el nino events show up fully in the satellite record. The 1997 - 1998 el nino didn't show up until mid 1998. Last years el nino may be the same, and wont fully show up until this year.

  27. The Little Ape That Could

    veranda posts. I drove a small SUV with a trailer to a nearby town to hire a machine to excavate the post holes and return it the same day. The machine had a 25 horsepower (HP) motor. My car had a 130 kW engine - roughly 175 HP.

    I think it was the Earh Day founder whom I will paraphrase, "All we have to do to ensure the complete destruction of the enviorment, is to keep doing exactly what we're doing now"

    and to further mangle things, Tolstoy 'Everyone thinks of changing the world, but no one thinks of changing himself.'

  28. A striking resemblance between testimony for Peabody Coal and for Ted Cruz

    It occurs to me that part of the reason people buy the "satellites are more accurate" line is that they never see graphs of the raw data.  I'm not sure where you could find a graph of the true raw data, and certainly would not be able to make one.  But Po-Chedley et al (2014) have a graph of minimally processed data:

    As I understand it, the top panel already has processing in the form of a rough alignment of means ot each satellites series.  At least, it would be stunning if such a close allignment of absolute values was achieved in raw data from satellites.  For comparison, here are the absolute alignment of satellite measurements of the solar constant:

    Certainly similar problems of alignment are experienced by Earth observing instruments measuring the IR spectrum, and I see no reason why the microwave observing instruments (which operate on the same principles as the IR and solar observing instruments) should be any different.

    Further, it is possible that the top panel in Po-Chedley's figure 3 also includes adjustments for problems with the hot target.

    In any event, the transition between the top panel and the third panel is not a given.  It represents serious adjustment to the data - and different teams disagree about how that adjustment is best done.  As a result they also significantly differ about satellite data trends.

  29. A striking resemblance between testimony for Peabody Coal and for Ted Cruz

    gregcharles @3, there are (at least) two graphs of satellite data used in the hearing.  The first, introduced by Happer, shows the average of RSS and UAH TMT data against the average of four ballon datasets.  It is shown above in the OP.

    The second, shown by Ted Cruz himself is of RSS TLT data from March 1997 to Novemer 2015, and is shown below:

    It should be noted that Admiral Titley's point about the start point is valid, but limited.  That is because the strong La Nina's in 2008 and again in 2001/12 contribute as much to the low trend as does 97/98 El Nino.  Ergo, in 2016 when RSS finally shows the current EL Nino (which it currently does not due to a well known lag), the trend will still be below what would be expected if there were no short term variations.

    I might add that watching the video was distinctly unpleasant.  It leads me to the belief that the purpose of a congressional hearing is to give the chair of that hearing the chance to see just how many lies he can fit into a three minute speach.  Virtually everytime Cruz stated something was the position of climate scientists, he got it egregiously wrong.

  30. Thorough, not thoroughly fabricated: The truth about global temperature data

    I assume Cruz is lying. 

    He is an accomplished debater.  He made a name for himself starting at Princeton in 1992 when he won the Top Speaker award for them at the North American Debating Championship.  When he went to Harvard Law one of his professors, Alan Dershowitz (a political liberal) said, "Cruz was off-the-charts brilliant".  As Texas Solicitor General Cruz argued many cases before the US Supreme Court, winning more than he lost. 

    Because his argument against doing anything about climate change because it isn't happening is so weak, the first thought that comes to my mind is he is lying.  Its just another debate to him. Top flight debaters can argue black is white, or white is black.  It doesn't matter.  He hasn't got much to work with in this climate debate, but he's giving it a shot. 

    He is cynically attempting to vacuum up the votes of people who actually believe NOAA, NASA, etc., just fabricate whatever it takes to contribute their bit to efforts of the global conspiracy of climate scientists who are all busy fabricating what they can so they can destroy the US economy or make their lawn die or whatever it is that they fear. 

  31. Thorough, not thoroughly fabricated: The truth about global temperature data

    If you go to the doctor and he takes your temperature and it is 60°F you don't ask him to call the mortuary, you take another reading.

    For a scientist to pretend that data readings are all correct, and to ignore known errors, would be dishonest - malpractice. 

    You make the observations and then you correct them as best you can.

  32. A striking resemblance between testimony for Peabody Coal and for Ted Cruz

    Was Cruz definitely using the TMT channel in the chart presented at "Data or Dogma"? I know he had trouble figuring out where the chart came from, before finally finding that it was RSS, but I never heard clearly whether it was TLT or TMT.

  33. One Planet Only Forever at 01:59 AM on 23 January 2016
    The Little Ape That Could

    Glenn,

    I appreciate the complexity of the issue and I really appreciate the time it takes to investigate, think about, develop and present an article like this.

    Perhaps a simple statement could be added in this document mentioning that, unlike in the other species, there is a very broad range of individual magnitudes of impact among humans.

    I believe that the different magnitudes of personal impact (not national or state/province per-capita levels) is a critical point to counter the misleading claims that the population number is the problem. The total number of people is only a concern. The combined total impact is the problem. Which makes the highest impacting individuals the real problem (and Global GDP has increased faster than population ... even Africa's GDP has risen faster than its population ... yet there are still many people who live incredibly brutal short lives ... the real concern)

    And if a separate article is developed to more fully present the issue of the range of impact among humans, it could be mentioned that deliberate misleading marketing must be considered when attributing impact to an individual which would be presented in more detail in a separate item, if developed.

    And that article about marketing can mention that Popularity and Profitability have fueled the increase of wealth and misleading marketing power of those who would willingly pursue unacceptable ways of benefiting any way they can get away with, distracting and distorting the results of the marketplace and democracy away from advancing humanity to a lasting better future for all, while creating unfustifiable impressions of advancement and superiority through the development of technological wonder toys for the wealthy and most fortunate that do not actually advance humanity. Those developments only create unsustainable impressions of advancement and superiority, while causing damage that no one who wants to enjoy benefiting from the activity and products wants to better understand the unacceptability of (especially not wanting to admit they do not deserve the perception of a Good Life that they were fortunate enough to get away with having developed).

    This last point is the sad reality of places like Alberta where I live. Many people hate(not an overstatement of their attitude towards it) the idea of climate science and anyone who tries to promote better understanding of it because it really does mean they did not deserve the type of living and working that they developed through the past 30 years. They will "Believe anything that attacks or questions the better understanding they are actually able to understand".

  34. The Little Ape That Could

    Hi Glenn. I wonder if you ever encountered my writings on the land surface available per person that you used? Some of your words "Not all that land is usable; some is ice caps, mountain ranges, deserts" seem similar to mine.
    I've been banging away in comment sections with these calculations for decades to counter those who try to claim that earth wasn't overpopulated because they pointed out that the global population could fit on the Isle of White or Rhode island etc. I first did the "reverse calculation" in 1966 for a school essay...

  35. The Little Ape That Could

    The arrogance is in the word "believe". It's not belief what has brought us forward, it's observation, comparing evidence and research, it's science. And before we realised we are just changing the climate of our fragile planet we already knew that we could even destroy the whole lot with nuclear weapons...

    Here half a minute of global warming jazz => https://www.youtube.com/watch?v=b3VVt76DeoQ

  36. The Little Ape That Could

    Mal Adapted #3:
    The oxygen released by the cyanobacteria may also have destroyed almost all the methane in the atmosphere and as a result reduced the greenhouse effect enough to trigger the first and most severe episode of Snowball Earth.

    So, this is indeed the story of the little cyanobacterium that could!

  37. The Little Ape That Could

    Excellent post Glenn. It summarises much of what I have been reading over recent years.

    It clearly illustrates that we humans through our sheer numbers and our ingenuity are now a terra-forming species with a global impact. Also, we humans are even more unique than we already were. With our broad scientific understanding and the technological developments that are a result, and our unravelling of the human genome and the new genetic engineering techniques that are being developed, we now have the ability to determine our own evolution. Unfortunately, our political systems, our economic policies, and our societies have not evolved to the point where we are capable of dealing with all the problems that these latest developments are causing. This is because the thinking of some very influential and powerful people is, unfortunately, stuck in the past as if they were still living in the world of 50 or 100 years ago when there weren't so many people and there appeared to be plenty for all.

    Rising greenhouse gases in our atmosphere, our eroding of our planet, our polluting of the atmosphere and the oceans, and the impact that we are having on global ecosystems, is very similar to a time when people living in cities and towns would simply throw their effluent and garbage into the street. Many people died of cholera and other nasty diseases as a result. The only difference today is that the throwing of our effluent and waste is having a global impact and unlike the conservatives of several hundred years ago, some conservatives today don't seem to want to build the sewers.

  38. A striking resemblance between testimony for Peabody Coal and for Ted Cruz

    Oh, John, I feel your pain. To see Ted Cruz in action I fear for America. Curry, Happer and Christy were just plain embarrassing. Though I think Mayer, Schatz, Peters, Markin and Nelson deployed Titley powerfully and science shone over dogma.

    I recently found (possibly through this site) James White's Colorado presentation to be a compelling expose of climate science clearly establishing the fundamental elements of climate change. White manages to sweep away the clutter of "complicated science" to reveal the undeniable basic principles.

    https://www.youtube.com/watch?v=FmyBAUR7GZU

  39. The Little Ape That Could

    Mal Adapted.

    Yeah this a point many people don't get. Particularly many geologists. Life has been an integral part of the chemistry and geology of the planet for most of it's history. It doesn't matter whether it is cyanobacteria or evolved austrolopithicenes, any species that grows numerous and or powerful can have surprising impacts.

    HK, neat graph. Visualising this sort of stuff is tricky.

    OPOF

    This was a difficult choice, all the things I would or wouldn't include. The more one adds the more the risk that I dilute the key message; 'that reaction of incredulousness about our capacity is misplaced'.

  40. One Planet Only Forever at 14:43 PM on 22 January 2016
    The Little Ape That Could

    Very thorough and interesting presentation.

    However, the point about population could be improved by categorizing the current human population in ranges of magnitude of impact of the individual. Not all humans are equal in impact (unlike the members of the other species listed ... there are admittedly some ranges of impacts among some of the domesticated species, particularly higher impacts for the industrial pharmaceutical factory farmed ones, the cheaper and quicker to produce - more profitable and popular - ones).

    If that was done it would probably show that the 200 to 300 million (the number of humans 2000 years ago) highest consuming and highest impacting people (including their share of the impact of activities they invest in to benefit financially from) are quite likely to be responsible for more than 90% of the unsustainable consumption and damaging impacts.

    If evaluated rigorously and rationally, including almost entirely attributing the consumption and pollution of stuff 'that wealthy investors profit from convincing people to desire (like plastic micro-beads and throw-away plastic)' to those wealthy investors it is likely that significantly fewer than 100 million people could be identified as being 'quite likely to be responsible' for more than 99% of the identifiable and quantifiable total global unsustainable over-consumption and negative impacts.

    A person tempted to buy into an appealing misleading sales pitch could be considered to be a hapless victim of fraud, not able to be deemed to be significantly responsible for the impacts of what they were tempted into desiring - addicts need to be helped to break free from their damaging addictions, not be blamed for becoming addicted. The Pushers need to be targeted.

    The number of successful pushers of damaging unsustainable over-consumptive addictions is the actual “Population Problem”.

  41. Tracking the 2°C Limit - November 2015

    As per the moderators suggestion, I have responded to angusmac across three posts elsewhere.  I will make one point in response here, however, because it gets to the core of why angusmac raised HCO temperatures on this thread in the first place.  To recap, angusmac argues that the MWP temperature should be used as the "preindustrial temperatures" for reasons sufficiently refuted above.  His reason for doing so comes down to his opinion that, "...“1.669 °C” above the 1961-1990 mean [and MWP temperatures] ... does not sound nearly as bad as 2 °C".  This in turn is related to his belief that "... many parts of the world exceeded the 2 °C limit [in the HCO] without any dangerous consequences and that these temperatures occurred when CO2 was at ≈ 280 ppm".  The idea is that if 1.67 C above the 1961-1990 mean is not bad, then neither is 0.75 C (2015 average, HadCRUT4) and neither is 2 C above the preindustrial average.  Ergo, rebaselining the 2 C guidline is justified to make that intuitively obvious.

    Marcott 2013 allows us to see how flawed that intuition is.

    Specifically, Marcott adds random variability to the stack of reconstructions used in the paper to make the annual scale variability of the reconstructions match actual annual scale variability.  The result is an increase of 0.13 C to the standard error.  It follows, that if we add 0.13 C to the standard deviation of the mean of the stack for each 20 year period in the full reconstruction, we get a good approximate measure of the potential range of annual temperatures for that 20 year period.  Note that due to autocorrelation, if temperatures are low for a given year in a 20 year period (or century), in a specific member of the stack, they will not be high within that 20 year period (or with slight qualification, within that century).  But because we do not know which member of the stack most closely approximate reality, the statistical data form all stacks gives us our best approximation of the temperature range.  From that in turn we can calculate an approximate probability of a particular temperature in any given year:

    The chart shows the probability of a given temperature (specified by year) in any given year over the Holocene.  The green line shows the probabilty of 1.5 C over the 1961-1990 mean.  It is consistently zero.  Even 2015 tempertures are shown to be relatively rare in the HCO, though 2000-2009 temperatures were commonplace.

    More interestingly, we can calculate the probability of those temperatures being reached at least once, in any year over a given period.  For the period 5500-9500 BP, it is a near certainty that even 2015 temperataures will have been reached at least once.  There is, however, only a 2% chance that temperatures reached 1.5 C above the 1961-1990 at any time in the HCO.  The chance that it reached 2 C above preindustrial for even a single year is negligible.

    It can therefore be seen that angusmac's assumption that high temperatures were commonplace in the HCO is simply false.  We are very nearly at the upper limit of HCO temperatures.  Nor is his assumption that HCO temperatures were always beneficial justified.  Indeed, given that almost all agriculture was invented between 30 degrees North and 30 degrees South (and all was invented between 40 north and 30 south), and given that temperatures in that latitude zone have actually increased since the HCO, his assumption of beneficial effect is very shaky indeed.

    Finally, for completeness, the probability of 1990-2009 twenty year average temperatures of the 950-1900 preindustrial baseline is 0.6%.  The probability of 1996-2015 twenty year average temperatures of the 950-1900 baseline is just 0.03%.  So much for natural variability being the cause.

  42. Real Skepticism About the New Marcott 'Hockey Stick'

    This is my final response on this page to angusmac's comment here.  In that comment, in addition to the three points addressed above he draws attention to the fact that the 19th and 20th century spike in the Marcott standard mean of reconstructions is not robust (something pointed out by Marcott et al in the original paper).  He reinforces the argument by comparing the final stages of Figure S3 to the equivalent Figure C8 from Marcott's thesis:

    He writes:

    "A difference of approximately 0.8 °C in the two versions of the reconstruction is presented in Figure 1 – yet they use the same proxies. Marcott et al do not address this significant difference by their “not robust” statement.

    ...

    In light of the above discrepancies in Marcott et al (2013), I would not recommend it as a reasonable paleo reconstruction."

    In the elided section, he adds the further, hypocritical criticism that Marcott's response to blog criticisms on a blog rather than formally through an corrigendum or explanandum published in the journal "...casts doubt on the robustness of the last 500 years of the reconstruction and perhaps even the entire paper".  The double standard in not assuming that the failure of critics to formally publish their criticisms "casts doubt on the robustness" of those criticisms is breath taking.  I will treat that "argument" with the contempt it disserves, and give it no further dicussion.

    With regard to robustness, Tamino explained it first and best.  It is entirely an artifact of the method of taking a simple average combined with the drop out of proxies towards the end of the record.  Using other methods such as the method of difference (see Tamino's post), or the RegEM method used as an alternative method in Marcott et al, results in a much smaller, but robuts uptick occuring in the 20th century only:

    Comparison of simple averages to the method of difference (or the RegEm method) shows the problem has little effect anywhere else in the reconstruction, and a scarcely discernible effect in the crucial years of the Holocene Climactic Optimum:

    Given that angusmac is familiar with Marcott's Q&A at Realclimate, and even with Marcott's thesis, he must be familiar with this explanation of the problem, and ergo that it makes no relevant difference to the reconstruction in the HCO.  Given that, I am surprised (to say the least) that he should raise this issue.

    This, of course, does not explain the difference in the terminal section of the stacks generated for the paper (S3) and the thesis (C8).  What angusmac does not show is the difference between Figure C8 and Figure C9 of the thesis:

    As can be seen, calibration issues in just one proxy were able to make a significant difference to the robustness of the reconstructions through the HCO.  Those issues were resolved in the paper, and the proxy consequently is used in the paper without problems.  While that proxy (ODP 984) terminates around 1400 AD, and therefore does not contribute to the lack of robustness of the terminal period, it is likely that similar improvements in calibration and/or terminal dates explains the difference between C9 of the thesis and S3 of the paper with regard to the final two centuries.

    Comparison of C9 and S3 shows the problem to only relate to the final two centuries which are not the point of the reconstruction, and which are not used to calibrate reconstruction temperatures to modern temperatures (which is done indirectly via the Mann 2008 reconstruction of temperatures over the last 2000 years).  From this it follows that there is no basis in this data to doubt the HCO reconstruction from Marcott et al.  

    Nor is any substantive reason advanced to show the changes in data handling with regard to calibration and possibly terminal dates between the two does not represent an improvement.  As it makes no difference to the substance of the reconstruction that is sufficient answer IMO.  If it does not satisfy angusmac, he can do the necessary leg work by enquiring of Marcott re all the precise differences between thesis and paper among which the full explanation must be found.

  43. The Little Ape That Could

    I find it interesting that you were born in 1957. The radiosondes developed the worldwide network in 1958. Since that year, they show .16 degree of warming in total. When you were talking about measurement I thought that might be an interesting factoid. 

    Moderator Response:

    [PS] Sloganeering and dangerously close to offtopic. Care to explain why you think that "factoid" is interesting? Actually, do so on an appropriate topic (such as here - where RATPAC graph does not appear to support your assertion)

  44. Real Skepticism About the New Marcott 'Hockey Stick'

    Continuing my discussion of Angusmac's comment here:

    Point (3) clearly misunderstands the nature of the Marcott reconstructions.  (The misunderstanding is quite common among people who discuss climate science on the internet.)  Specifically, while the mean of the stack of reconstructions has a resolution of approximately 300 years, the reconstructions themselves (as shown in figure S3, see Comment 101 above) have a resolution of 20 years.  They are therefore quite appropriately compared to decadal temperatures.  Further, in generating Figure 3 (see comment 101 above), which is the crux of Marcott et al, Marcott et al added noise to the reconstructions so that their variability matched the annually resolved Mann 2008 reconstruction.  The statistical distribution is, therefore, quite appropriately compared to annual temperatures.

    Given this, it is reasonable to criticize graphs that show only the stack mean vs modern temperatures.  The falsely give the impression that we are experiencing temperatures never experienced before since the invention of agriculture.  Rather, modern twenty year averages should be compared to the individual reconstructions in the stack, like this:

    As you can see, even the 1996-2015 average was probably experience many times (if briefly) in the Holocene, but we are pushing towards the upper temperature limit of the Holocene.  More significantly, the rate of increase of temperature over the last century is certainly in the highest 5% of holocene temperature trends, and may well be unprecedented.  It is also ongoing.

    More later.

  45. The Little Ape That Could

    Glenn:
    Your article inspired me to create this pie chart of the Earth’s land mammals based on a comment by Andy Skuce in December.

    Land mammals by body weight

    If I counted all the squares correctly, wild land mammals represent less than 3% of the total mammalian biomass on land today. And that isn’t the whole story, as many of the remaining populations of wild land mammals are also harvested by us. For instance, humans are the most common predator of the moose in Norway (about 36,000 shot every year), so even the tiny, green part of the pie chart is largely controlled by humans.

  46. The Little Ape That Could

    Up until about 2.5 billion years ago, there was no free oxygen on Earth, either in the oceans or the atmosphere. All life was anaerobic. Then cyanobacteria evolved. Cyanobacteria, formerly call blue-green algae, photosynthesize by using hydrogen atoms from water molecules to reduce CO2, releasing molecular oxygen (O2) as a "waste" product.

    For millions of years, the newly-released molecular oxygen immediately combined with reducing substances in the oceans, but eventually those were used up, and free oxygen began to accumulate.

    Free oxygen was toxic to the anaerobic life dominant at the time. A mass extinction ensued, and the only survivors were those that could protect themselves from the corrosive effects of O2. Eventually aerobic metabolism evolved. Aerobic metablism uses molecular oxygen to convert much more of the chemical energy in organic compounds to energy.  Life again spread to occupy the globe.

    This is the story of the little cyanobacterium that could.

  47. Ted Cruz fact check: which temperature data are the best?

    Recommended supplementary reading:

    Thorough, not thoroughly fabricated: The truth about global temperature data by Scott K Johnson, Ars Technica, Jan 21, 2016

  48. The Little Ape That Could

    Glenn: If you expand this excellent article in the future, you may want to  add a new section on the amount of manmade plastics that has been created by humans and released into our biosphere.  For example...

    By the Year 2050, There Will Be More Plastic Garbage in the Ocean Than Fish by Tom McKay, Science.Mic, Jan 19, 2016

  49. The Little Ape That Could

    Some fantastic perspective here on our overall impact/footprint on the planet. Thanks for posting this.

  50. It warmed before 1940 when CO2 was low

    tcflood

    These graphs, also from GISS, show different regions - Norther exa-tropics, tropics and southern exa-tropics. Quite different pictures.



    Also this paper might be interesting, particularly figure 11.

Prev  507  508  509  510  511  512  513  514  515  516  517  518  519  520  521  522  Next



The Consensus Project Website

THE ESCALATOR

(free to republish)


© Copyright 2024 John Cook
Home | Translations | About Us | Privacy | Contact Us