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Search for prudent path

Comments matching the search prudent path:

  • The Climate Shell Game

    Evan at 05:56 AM on 23 March, 2022

    Let me add the following comment to this discussion. Table 1 shows a path that is almost incomprehensibly challenging. The consequences of not meeting that incomprehensible challenge is dire. Yet people are confidently placing their hope and trust in forecasts and predictions when nothing we've done, to date, has slowed the upward acceleration of the Keeling Curve.

    To me, this indicates that we must do all that we can to reduce GHG emissions. It would be a mistake to trust in technologies that have yet to be deployed at a scale to make a difference. It seems prudent to start campaigns to get people to consume less.

    There is no guarantee of success. But we increase our odds for success by not just relying on wonder technologies, but being prudent and encouraging people to reduce consumption.

  • Trump administration refuses to consider that 97% of climate scientists could be right

    ubrew12 at 06:20 AM on 30 May, 2018

    "There’s a 97% expert consensus... betting... humanity... on a... 3% long shot is a bad idea... Prudent risk management dictates that we should be taking serious steps...That’s why Americans buy... insurance"  There is another way of illustrating the 'long shot' Republicans are taking:  I downloaded (from here & here) the Vostok ice core temperature record and calculated the century-by-century temperature change in Antarctica going back 400,000 years.  This meant throwing out some data and duplicating others to get time intervals of between 80 and 140 years, i.e. around a century.  The result was 3,670 data points representing temperature change/100 years, for each century going from ~1800AD to ~400,000BC.  The average was 0.0C, as you might expect.  The standard deviation was 0.34C, and its a normal distribution, not skewed in any way.  The 20th century temperature change was 0.8C, so the probability that change was 'natural' is 2% (=1- erf[{0.8/0.34}/2] ). 

    But Vostok is just one place on Earth.  It likely is much more variable than the Earth overall.  I looked at the last 27 centuries of Vostok, and the 20 centuries of the Pages_2k tree ring database, to evaluated how much more variable Vostok is.  I got a standard deviation of 0.9C for Vostok station and 0.08C for Earth overall. If you use half the standard deviation I got for Vostok as a conservative value for Earth, or 0.17C, then the likelihood that the 20th century temperature rise was natural, based on the last 400,000 years of natural climate-change data, is 0.0003% (=1- erf[{0.8/0.17}/2] ).  Clint Eastwood said something in 'Dirty Harry' that should be said to Trump and the GOP: "Do ya feel lucky, punk?  Well, do ya?"

  • CO2 limits will hurt the poor

    jdixon1980 at 01:12 AM on 30 August, 2013

    A dissenter/denier/contrarian/whatever friend of mine keeps bringing up the issue of forgoing fossil-fuel based industrialization being a lost opportunity to alleviate the world's worst poverty.  (We generally have these discussions on my Facebook timeline.)  He also brings up the whole gamut of meritless "scientific" arguments (solar activity, Milankovitch cycles, cosmic rays, nameless "natural cycles," platitudes about "uncertainty/complexity") as well as the usual conspiracy theories about AGW theory being a commie plot to bring down the west, etc., all of which made it hard for me to take his poverty argument seriously for a long time.  

    I'm not even sure that alleviation of poverty argument is a good argument against aggressive emissions reductions. It's just that I haven't been able to find any satisfying discussion of it on the web.  This may be because the kind of analysis I would ideally like to see would probably take a lot of experts a long time to put together: I would like to see analysis of an emissions pathway that at least a majority of scientists would consider prudent (i.e., at a bare minimum avoiding any significant risk of a "Hell on Earth" scenario within the next X number of years - 100? 150?, such as requiring mass evacuations of coastal cities and low-lying island nations, etc.) in terms of what increase in power generation per capita can feasibly be distributed to the poorest regions of the world within the constraints of that emissions pathway by X date, what the difference is (if any) between that increase and the increase that would be feasible by X date in a free-for-all scenario with no emissions restrictions, and what that difference implies in terms of a sacrifice in quality of life (if any) that today's poor will have to make for the sake of avoiding climate catastrophe.  I have no idea what that kind of analysis would entail, or whether it might take so long or depend on so many political unknowns (for example) that it wouldn't be worth doing, but I would like to see somebody take a stab at it.  

    Of course, there is another elephant in the room, which is that if our rate of consumption of global resources across the board already far exceeds Earth's ability to replenish them (see "Earth Overshoot Day," "Ecological Debt Day," which the Global Footprint Network says that we hit this year on August 20), then it's frightening to think what would happen if every country in the world had a population that consumed like America's or Europe's populations.  This doesn't change the fact that some people live on appallingly little and consume far less than their fair share of resources, but it would be crazy to pursue policies aimed toward making sure that everybody in the world overconsumes to the same degree as I do in America.  They have a right to scale up consumption, but not to our current level, and I have no right to remain at my current level of consumption.  Reducing inequality is a noble goal, but if the Global Footprint Network is anywhere close to right, then reducing inequality will have to involve meeting somewhere in the middle or we are screwed.


  • Lukewarmerism, a.k.a. Ignoring Inconvenient Evidence

    Rob Honeycutt at 05:37 AM on 13 February, 2013

    Nick...  Yup.  And I believe this is the original source of the colored and doctored version:

    You can catch these pretty easily when they pop up because most of the Idso's MWP Project graphs are doctored in various ways.  The always add in their own notations of where MWP, LIA, etc occur.  They delete any aspect of the original that might be inconvenient and then they add the notation "Adapted from..."

  • Skeptical Science Upgrade

    citizenschallenge at 14:22 PM on 14 January, 2013

    The menu bar and drop downs seem to be working fine for me

    {Mac OS X - ver 10.8.2 - Safari }

    However these links were broken:

    lessons from predictions
    trend calculator
    climate myths
    prudent path
    OA not OK


    Other than that, SWEET - it seems to work much faster and
    I clinked around a bunch, including translations... never appreciated how many translations you've got. Bravo!
    It all worked swell !

    Although - about your "Donation"
    too bad PayPal is the only option you have.
    Not like I could donate much, but for you folks, I could definitely scratch some coin together. But I don't do the PayPal.
    ~ ~ ~

    Anyways, thanks for all your collective efforts, they help.

    You folks are awesome !
  • Obama, Romney, and Various National Climate Policies Around the Globe

    M Tucker at 06:46 AM on 12 September, 2012

    DSL, if you think I’m not disturbed then I guess I need to use more forceful language. People who deny climate change have nothing to say about adaptation because it is unnecessary because nothing unusual is happening. Please direct me to any mitigation in progress that has done anything to end the relentless rise in CO2 or even slowed the increase. I mean actual numbers because I am well aware of the pathetically small increases in clean energy installations.

    I’m not saying we should not try to mitigate this tragedy I’m saying that the majority of the polluting nations are doing nothing to mitigate this tragedy and they will continue as before.

    China is the most polluted nation on earth at the moment. What little installations of wind and solar China has actually done is insignificant to the amount of coal they consume. And they are only consuming more. Their domestic sources are not enough to keep up with their relentless demand. So much so that they have created an environmental nightmare in Mongolia…AND THAT IS NOT ENOUGH. China requires coal to be imported from Australia and Indonesia and even from as far away as the US. They are a coal consuming monster. And will they simply walk away from those coal power plants 10 or 15 years from now when they are still in their prime? I doubt it because they are very economically pragmatic people. So I’m not calling for governments to adapt to the climactic catastrophe thundering toward us I am saying that prudent individuals need to look for adaptive strategies because our governments have other priorities.
  • 2012 SkS Weekly Digest #2

    funglestrumpet at 09:04 AM on 17 January, 2012

    Rating: about 8/9


    Make the Monckton Myths, Christy Crocks etc section more formal in layout (looks a bit childish at present). It should have a title, such as: Prominent Mis-Informers.

    Move the OA not Ok, Interactive ... (needs checking as it appears broken!), Prudent Path and Lessons ... to their own separate section – they are not myths or crocks etc.

    Add a list of threads currently being discussed on this site.

    Have provision for visitors to suggest a new thread (the number of times something is suggested will indicate how important it is to the public at large).

    Have provision under the Comments tab for having a list all personal comments made by the person logged on and include references to their name so that replies are easy to see. At present, there are so many topics each week, remembering what one has said is a bit daunting. Then finding the comments and searching for replies is all a bit much. I now tend to comment and leave it at that. If people reply then I often don’t get round to finding out. It goes without saying that these should be in date order with latest at the top, and have a limit to one month, say. If possible, have an automatic email notification of replies posted. Overall, this would require a discipline regarding posting replies, such as: 'name'@X being required. Perhaps even having provision for replying to the actual post in situ, as some sites do (tabbed in to mark a reply), which would make the argument easy to follow (and drive John Cook mad, I suspect).

    Have links to all other prominent sites dealing with the topic of climate change. I suggest that this should even include WUWT. It would tell visitors that this site is sufficiently confident of the veracity of what it posts that it doesn't fear what other sites say. Have it near the myths section and the visitor will know that they can always return to see what the grown ups say.

    Leave a comment not yet submitted in a draft folder if the writer goes off somewhere else on the site in order to check something instead of just wiping the comment clean and lost to all (said with feeling!)

    Over and above all that, I am extremely grateful for all the hard work that is put into making this site as excellent as it is, thanks!
  • SkS Responses to Pielke Sr. Questions

    Albatross at 12:32 PM on 22 September, 2011

    DSL and others,

    In my post @111 I do try and clarify the situation by reiterating a key point. Readers will note that that post has also been edited.

    With that said, it is very unfortunate that Dr. Pielke Sr. elected to bow out of the discussion here, and while he may not share my sentiment, I for one do appreciate him coming here. Yes, discussion was heated at times, but as anyone who has undergone peer-review or has been in academia, that is how these matters are for often discussed and debated.

    I want to acknowledge that for Dr. Pielke to post here must have been difficult him at times, not in terms of material of course, but because not many people share his beliefs and opinions. I am glad that Dr. Pielke agrees that reducing GHG levels is a primary concern. So it was not all bad and some common ground was achieved on key issues-- at least that is my impression (Dr. Pielke seems to disagree, see link to his blog post below).

    Where the conflict arises is how Dr, Pielke chooses to convey his position to policy makers, the public and the House of Representatives. Rather than making unequivocal and reasonable statements as he did here,

    "The emission of CO2 into the atmosphere, and its continued accumulation in the atmosphere is changing the climate. We do not need to agree on the magnitude of its global average radiative forcing to see a need to limit this accumulation. The biogeochemical effect of added CO2 by itself is a concern as we do not know its consequences. At the very least, ecosystem function will change resulting in biodiversity changes as different species react differently to higher CO2. The prudent path, therefore, is to limit how much we change our atmosphere."

    Dr. Pielke instead presented politicians in March 2011 with hypotheses that they have very little hope in grasping and which appear, to them at least, to focus on uncertainty and focus on issues secondary to GHGs. This is what he chose to say to them, the very people who are in a position to take prompt and meaningful action on AGW:

    "1. Research has shown that a focus on just carbon dioxide and a few other greenhouse gases as the dominant human influence on climate is too narrow, and misses other important human influences.

    2. The phrases “global warming” and “climate change” are not the same. Global warming is a subset of climate change.

    3. The prediction (or projection) of regional weather, including extremes, decades into the future is far more difficult than commonly assumed. As well, the attribution of extreme events to a particular subset of climate forcings is scientifically incomplete, if the research ignores other relevant human and natural causes of extreme weather events.

    4. The climate science assessments of the IPCC and CCSP, as well as the various statements issued by the AGU, AMS and NRC, are completed by a small subset of climate scientists who are often the same individuals in each case."

    Quite different from his statement made here, and hardly conducive to elucidating the pertinent issues for people who are not familiar with the science, or alerting them to the urgency at hand. Why would he do that?

    What troubles me very much, and what should perhaps concern other people following this, is that within hours of bowing out here, Dr. Pielke made this post on his blog.

    If people here make assertions or challenge the content of a blog post are (within the limits of the "Comments Policy") free to do so. Many diverse views and opinions are voiced daily here at SkepticalScience. Some regular skeptics who post here have been discussing the same issue for months now.

    In contrast, no-one except Dr. Pielke has that freedom or privilege at Dr. Pielke's blog. Him airing that post is not acting in good faith in my opinion, rather it is very much trying to spin the situation in his favour by making unsubstantiated and demonstrably false allegations that cannot be challenged on his site. Consequently, his opinion and understanding of the situation become fact to his audience.
  • SkS Responses to Pielke Sr. Questions

    Albatross at 05:23 AM on 22 September, 2011

    Dr. Pielke @94,

    "3) Climate models are certainly not perfect, but are useful tools which have made fairly accurate climate projections thus far.

    No, they models have not shown skill at predicting changes in regional climate statistics."

    With respect, you are shifting the goal posts and arguing strawmen. Dana was very likely referring to 'global climate', and you insist on focusing on regional impacts. Yes, those are of course important, and you seem to be dismissing out of hand the wealth of work that has been done on downscaling. Additionally, you know as well as I do that because NWP models (e.g., WRF) accurately or perfectly simulating certain mesoscale features/processes does not render them useless or of no value. Besides, we know that despite their imperfections and limitations NWP models are very useful, as are AOGCMs; you also ignore the fact that they continue to improve.

    I find it odd that AOGCMs are good enough to support your view that regional and local land use change is a first-order global climate driver (e.g., you citing Takata et al.) and by extension that we should place less focus on Carbon, but you then turn around and say that those same models are no use for guiding climate policy. Regardless, paleo climate shows us that we best take the most prudent path and significantly reduce our emissions to avoid some major changes. Models are but one of several tools that we can use for guidance.

    "I also have concluded that the computationally expensive climate models, when used for multi-decadal predictions, have not told us anything of demonstrated added value beyond what can be achieved with just global energy balance models."

    I respectfully disagree, and so do many of your colleagues. I also note that this is a logical fallacy on your part. You are at the same time arguing that simple models are good at today's sophisticated AOGCMs while also arguing that the models are not complex enough and do not account adequately for land cover and land use changes or adequately simulate the surface processes. You seem to want to have it both ways.

    And no, simple energy balance models do not cut it, just as Roy's simple one-box model does not cut it (see Trenberth et al. 2011). Those type of models are useful for teaching students the basic concepts and for conducting simple experiments.
  • SkS Responses to Pielke Sr. Questions

    bartverheggen at 21:44 PM on 21 September, 2011

    Pielke Sr's reply to Q3 is worth noting, as it highlights that people can agree on the broad question of what needs to be done, while disagreeing about details of the scientific picture. Quoting Herman Daly: "if you jump out of an airplane you need a crude parachute more than an accurate altimeter."

    "3. Do you agree that continuing on our current business-as-usual emissions path presents an unacceptable (in your opinion) risk to the biosphere and to human society in general within the next century?

    Pielke Sr:

    Of course. The emission of CO2 into the atmosphere, and its continued accumulation in the atmosphere is changing the climate. We do not need to agree on the magnitude of its global average radiative forcing to see a need to limit this accumulation. The biogeochemical effect of added CO2 by itself is a concern as we do not know its consequences. At the very least, ecosystem function will change resulting in biodiversity changes as different species react differently to higher CO2. The prudent path, therefore, is to limit how much we change our atmosphere.

    By continuing to argue on global warming and its magnitude, I feel you, and others, are missing an opportunity to build up a larger consensus on how to properly deal with the myraid ways we are altering the climate and the environment, in general. Even if there were no global warming (or even cooling) in the coming decades, we still need to limit how much we change the environment (including land use change, nitogren deposition, CO2 etc)."
  • SkS Responses to Pielke Sr. Questions

    pielkesr at 07:28 AM on 21 September, 2011

    My response and answer to your questions might be clearer in my weblog post on this but I have entered it here too.

    Dr. Pielke's questions are underlined in the text below, and the answers from SkS follow.

    1. Of the two hypotheses below, which one do you conclude is correct? (see Dr. Pielke's post for the two hypotheses offered)

    The two aren't mutually exclusive, and both are correct. CO2 is the dominant radiative forcing causing the current global energy imbalance.

    R.Pielke Sr. Response -

    First, let me thank you for moving on to actual science issues.

    In response to your first answer, they actually are separate hypotheses and only one of them can be correct.

    We discuss this in

    Pielke Sr., R., K. Beven, G. Brasseur, J. Calvert, M. Chahine, R. Dickerson, D. Entekhabi, E. Foufoula-Georgiou, H. Gupta, V. Gupta, W. Krajewski, E. Philip Krider, W. K.M. Lau, J. McDonnell, W. Rossow, J. Schaake, J. Smith, S. Sorooshian, and E. Wood, 2009: Climate change: The need to consider human forcings besides greenhouse gases. Eos, Vol. 90, No. 45, 10 November 2009, 413. Copyright (2009) American Geophysical Union.

    where we wrote

    "Hypotheses 2a and 2b are two different oppositional views to hypothesis 1. Hypotheses 2a and 2b both agree that human impacts on climate variations and changes are significant. They differ, however, with respect to which human climate forcings are important.......... we suggest that the evidence in the peer- reviewed literature (e.g., as summarized by National Research Council (NRC) [2005]) is predominantly in support of hypothesis 2a, in that a diverse range of first-order human climate forcings have been identified."

    "We therefore conclude that hypothesis 2a is better supported than hypothesis 2b, which is a policy that focuses on modulating carbon emissions. Hypothesis 2b as a framework to mitigate climate change will neglect the diversity of other, important first- order human climate forcings that also can have adverse effects on the climate system. We urge that these other climate forcings should also be considered with respect to mitigation and adaptation policies."


    "The evidence predominantly suggests that humans are significantly altering the global
    environment, and thus climate, in a variety of diverse ways beyond the effects of human emissions of greenhouse gases, including CO2. Unfortunately, the 2007 Intergovernmental Panel on Climate Change (IPCC) assessment did not sufficiently acknowledge the importance of these other human climate forcings in altering regional and global climate and their effects on predictability at the regional scale. It also placed too much emphasis on average global forcing from a limited set of human climate forcings.

    2. Of the two perspectives below [from Mike Hulme], which one do you agree with? (see Dr. Pielke's post for the two perspectives offered)

    Again, the two perspectives are not mutally exclusive, and both are correct. As Hulme notes, they are simply two different framings. In terms of climate policy, the second framing is probably more appropriate, as addressing climate change will involve more than just CO2 emissions reductions.

    R.Pielke Sr. Response -

    If the second framing is more appropriate, we have made progress towards agreement as that framework fits with hypothesis 2a. I also suggest you contact Mike Hulem for his view whether both perspectives can be "correct".

    3. What is your preferred diagnostic to monitor global warming?

    SkS doesn't have a preferred diagnostic - all lines of evidence must be taken into account. It's important to look at all the data in totality to monitor global warming (surface temperature, ocean heat content, atmospheric temperature, TOA energy imbalance, sea level rise, receding ice, etc.).

    R.Pielke Sr. Response -

    Global warming or cooling involves changes in Joules of heat in the climate system. This involves changes in heat in the oceans, land, atmosphere and cryosphere. As concluded by Jim Hansen and others, the ocean is by far the component of the climate system where the large majority of this heating and cooling occurs. Receding ice, surface temperature, atmospheric temperatures make up only a relatively small portion of global warming and cooling.

    What is your best estimate of the observed trends in each of these metrics over the last 10 years and the last 20 years?

    10-year trends are generally not statistically significant (see Santer et al. 2011, for example). The approximate best estimate observed trends for some of these metrics over the last ~20 years are as follows. TLT: 0.18°C per decade. Surface temperature: 0.18°C per decade. Ocean Heat Content (OHC) upper 700 meters: 6.3 x 1022 J per decade. Sea level rise: 32 mm per decade. Arctic sea ice volume: -2900 km3 per decade. Glacier mass balance: -180 mm w.e. per decade.

    4. What do the models’ predict should be the current value of these metrics?

    The surface temperature change is roughly consistent with model predictions, though perhaps a bit on the low end. The predicted TLT trend is approximately 0.26°C per decade. Sea levels are rising faster and Arctic sea ice is declining far faster than models predict.

    OHC in the upper 700 meters increased more than the models expected from 1961 to 1999, and has increased less than models project since 2003. There are a number of factors that may explain the recent discrepancy:

    as noted above, this is too short of a timeframe for a valid statistical evaluation;
    models generally do not take the increases in aerosol emissions over this period into account;
    there is a wide range of estimates of upper 700 meter OHC trend since 2003, varying by nearly two orders of magnitude; and the oceans are much deeper than 700 meters, and the so-called "missing heat" may very well reside in the deeper oceans (i.e. see Meehl et al. 2011).
    We have discussed this subject previously here and more recently here, taking the deep ocean into account.

    One reason that we like to rely on multiple lines of evidence, rather than depend on one single indicator, is that any one can be wrong. The history of the UAH measurements comes to mind: the measurements were in conflict with other methods for tracking temperature change (and with climate model projections) for over a decade; eventually, most of the discrepancy was resolved (in favor of the models) only after very subtle analysis of the physical behavior of the instruments.

    R.Pielke Sr. Response -

    The oceanographers who work with the ocean heat data are convincing (at least to me and a number of other colleagues) that since the completion of the Argo network, it is a robust metric (within defined uncertainty bars) such as Josh Willis placed on the figure he provided me for the article

    Pielke Sr., R.A., 2008: A broader view of the role of humans in the climate system. Physics Today, 61, Vol. 11, 54-55.

    5. What are your preferred diagnostics to monitor climate change?

    That depends on how "climate change" is defined, but again, it is necessary to look at all lines of evidence and data.

    R.Pielke Sr. Response -

    You avoided answering this question. This is actually an essential issue to resolve. The NRC (2005) report [] defines climate change as

    "The system consisting of the atmosphere, hydrosphere, lithosphere, and biosphere, determining the Earth’s climate as the result of mutual interactions and responses to external influences (forcing). Physical, chemical, and biological processes are involved in interactions among the components of the climate system. "

    This is much broader than just global warming and cooling. Please clarify your view.

    6. Is global warming (and cooling) a subset of climate change or does it dominate climate change?

    Again, that depends on how "climate change" is defined. Long-term global temperature and climate changes are both ultimately caused by global energy imbalances.

    R.Pielke Sr. Response -

    The recognition that climate changes can occur without any global energy imbalance is central to the much needed broader view of how humans are altering the climate system. Please clarify what is "climate change" in your view.

    Now that we have answered your questions, there are a few issues on which we would like to understand your perspective, Dr. Pielke.

    SkS Questions for Dr. Pielke

    1. Approximately what percentage of the global warming (increase in surface, atmosphere, ocean temperatures, etc.) over the past 100 years would you estimate is due to human greenhouse gas emissions and other anthropogenic effects? And the past 50 years?

    This is a good question. It is a still incompletely understood mix of a variety of human caused radiative forcings (e.g. CO2, methane and several other greenhouse gases, land use/land cover change, black carbon (soot), sulphates, and other aerosols) and natual climate variations.

    Several years ago I did a back of the envelope estimate and came up that ~26% of the positive radiative forcing was from CO2; see slide 12


    Pielke, R.A. Sr., 2006: Regional and Global Climate Forcings. Presented at the Conference on the Earth’s Radiative Energy Budget Related to SORCE, San Juan Islands, Washington, September 20-22, 2006.

    This number certainly changes through the last 100 and the last 50 years, and remains uncertain.

    The complexity of these radiative forcings is discussed in some detail in NRC (2005) - Despite the vigor with which you criticize Roy Spencer, he actually has been instrumental in elevating our awareness that natural variations in cloud cover, as a result of temporal variations in atmospheric circulation features, as causing long term variations in the TOA radiative imbalance.

    2. Do you find Spencer, Lindzen, and Christy's arguments that equilibrium climate sensitivity is in the ballpark of 1°C or less for doubled atmospheric CO2 plausible? If so, how do you reconcile this low climate sensitivity with the paleoclimate record, for example needing to explain ~5°C swings in average global surface temperature between glacial and interglacial periods (i.e. see the figure below from Hansen and Sato 2011)?

    I do not find the glacial and interglacial periods as useful comparisons with the current climate since when we study them with models, they have large differences in imposed terrain (e.g. massive continetal glaciers over the northern hemisphere which will alter jet stream features, for example).

    In any case, I find the discussion of the so-called "climate sensitivity" by all sides of this issue as an almost meaningless activity. I posted on this in

    So-Called “Climate-Sensitivity” – A Dance On The Head Of A Pin -

    3. Do you agree that continuing on our current business-as-usual emissions path presents an unacceptable (in your opinion) risk to the biosphere and to human society in general within the next century?

    Of course. The emission of CO2 into the atmosphere, and its continued accumulation in the atmosphere is changing the climate. We do not need to agree on the magnitude of its global average radiative forcing to see a need to limit this accumulation. The biogeochemical effect of added CO2 by itself is a concern as we do not know its consequences. At the very least, ecosystem function will change resulting in biodiversity changes as different species react differently to higher CO2. The prudent path, therefore, is to limit how much we change our atmosphere.

    By continuing to argue on global warming and its magnitude, I feel you, and others, are missing an opportunity to build up a larger consensus on how to properly deal with the myraid ways we are altering the climate and the environment, in general. Even if there were no global warming (or even cooling) in the coming decades, we still need to limit how much we change the environment (including land use change, nitogren deposition, CO2 etc).

    4. Do you agree that continuing on our current business-as-usual emissions path presents an unacceptable (in your opinion) risk to marine ecosystems in the form of ocean acidification within the next century?

    Regardless of whether we reduce the alkalinity of the oceans (since there may be buffering from the added CO2 through mixing from below) we will be altering ecosystem function both in the oceans and in the atmosphere. Since we do not know the consequences of doing this, the smart thing to do is to work towards reducing the extent we alter the chemisty of the oceans and the atmosphere.

    5. Do you think that we should begin to move towards a low-carbon economy, thereby reducing anthropogenic GHG emissions?

    I am very much in favor of energy sources which minimize the input off gases and aerosols into the atmosphere. Much of my career has been involved with reducing air pollution (both in research and in policy). What we should move towards is an economy with as small a footprint on the natural environment as possible.

    In terms of how to do this with respect to carbon emissions, I completely agree with my son's perspective as he presents in The Climate Fix -
  • Rising Oceans - Too Late to Turn the Tide?

    apiratelooksat50 at 06:20 AM on 3 August, 2011

    I don't know if it is too late to turn the tide, or not. I really don't think it is possible to turn the tide. Even if we eliminate all of our FF use and land altering activities, there is still good ole Mother Nature to deal with and she will continue her cycle of warming and cooling.

    I firmly believe that the most prudent path for addressing current perceived negative climate change issues, and possible future negative climate change issues is to use technology and innovation. We can easily address the current rate of SLR, and the anticipated increased rate over the next few decades. In the meantime we should be working diligently on developing dependable, affordable and emission free energy sources.
  • Rising Oceans - Too Late to Turn the Tide?

    apiratelooksat50 at 07:31 AM on 1 August, 2011

    Eric the Red
    Thanks for stating my point better than me. I honestly want to know about the ecosystems that are definitely in danger due to SLR, not the ones that may be.

    It is a much more prudent path to take to address issues that may arise. SLR is going to be slow in human terms regardless of how fast it may be in geological terms.

    And, again, let me state that there are an awful lot of actions that we should be doing anyway that are helpful for the "health" of this planet. Many of those actions would be beneficial in reducing CO2 emissions.
  • Glaciers are growing

    Tom Curtis at 01:33 AM on 6 July, 2011

    NikFromNYC @16, I am unsure what point there is to your post other than to sow confusion. The topic of the main article above is the ongoing retreat of glaciers world wide, something you do not dispute.

    You do attribute the retreat of Himalayan glaciers to black carbon (soot) from the Indian industrialisation, and indeed that is probably a factor; but it is hard to dispute that they would continue melting in a warming world, even in the absence of black carbon. More importantly, the ongoing retreat of Andean, African, North American and New Zealand glaciers shows the primary cause of retreat is a global factor, specifically the rise in temperatures through the 20th century.

    You throw out a couple of of topic canards. First you suggest that Antarctica is cooling. In fact it is warming:

    The map on the left is from O'Donnell et al, a team closely associated with Climate Audit, and one of the very few pieces of actual science produced by people associated with Climate Audit. It is not without its problems, including a number of methodological choices that introduce a cooling bias to their study, but even so it shows a clearly warming Antarctica with some cooling regions.

    You also mention the IPCC's error with regard the Himalayan glaciers. The incorrect prediction of glacial melts was made by the IPCC Working Group 2, which looks at the impacts of global warming, not the science of global warming. It therefore is no reason to call into question the very high standard of the IPCC Working group 1 reports. What is more, it is just one error from among tens of thousands of factual claims across 3000 pages of the IPCC report. An error rate of less than 1 in 10,000 is no reason to doubt the general reliability of the IPCC. In contrast, many of the more highly touted denier documents struggle to keep their error rate down to 1 per sentence. Having said that, may I suggest you take comment about that error to the appropriate topic (which I suggest you read).
  • The Last Interglacial - An Analogue for the Future?

    Somes_J at 18:19 PM on 24 June, 2011


    Sorry if this is a double post, the board software seems to have eaten my last one.

    I'm curious about something regarding the Eemian as an analogy to a future warmer world. The Eemian was a period of the Green Sahara.

    "Approx. 125,000 - 120,000 y.a., moistest phase of the Eemian Interglacial (Isotope Stage 5e). Rainforest occupied a far greater area than at present, and rainfall was generally higher over north Africa. Data are sparse, mainly coming from long cores recording pollen and dust flux off the west coast of Africa. From these indicators, it seems that the situation generally resembled that of the early Holocene, around 8,000 14C y.a. General Eemian 'optimum' conditions in north Africa are summarized in map form by Frenzel et al. (1992) and by van Andel & Tzedakis (1996)."

    Africa during the early Holocene looked like this:

    A good deal wetter than present Africa, apparently. But the IPCC predicts drying in tropical regions in a warmer world, as I remember.

    Why is this? Is it because the tilt of Earth's axis, orbit etc. were different in the Eemian?

    I also notice that from looking at paleoclimates warmer periods tend to be wetter. As I remember the IPCC projections are a mixed bag here, with drying in tropical regions and moistening in temperate ones. There are exceptions to the first (e.g. Mousterian Pluvial, US Southwest was wetter than the ice age), but the ice age tropics had less forest, Eemian tropical Africa had less desert, and as I remember from a paper I read on the Pliocene warm period Pliocene warm period Africa also had less desert.

    I'm getting most of my information from here:

    I'm not saying the IPCC's wrong, I'm just curious about the percieved difference. This site seems to have many knowledgeable people so I thought this might be a good place to ask about it.

    Also I just want to clarify I'm not saying I think this would mean global warming is a good thing or shouldn't be prevented. I wouldn't mind living in the world of the Eemian, it looks quite pleasant to me and more inviting than our drier and colder world, but putting our planet through a rapid change from present world to Eemian world while our present civilization is living on it does not strike me as a prudent plan. If recreating the Eemian world is possible and a good idea I'd much rather it happen as part of a managed and responsible geoengineering project by a wealthy and responsible future, not an out of control side effect of energy generation by the poor present, allowed to happen because of short-sightedness and apathy.

    I'm just interested in why the apparent difference between paleoclimate data and the projections happens.

    An interested layman.
  • There's no room for a climate of denial

    Albatross at 13:19 PM on 11 June, 2011

    Norman @57 and 58,

    As I said before "You will disagree I'm sure, but your failure to recognize the err of your arguments and only further enforces the OP's point." And your posts have just affirmed that.

    One has to look at the body of evidence from around the globe when it comes to extremes, one also has to do some pretty sophisticated statistics. There are many studies by respected scientists (Dai, Trenberth, Zwiers, Allen, Stott, Santer and many more) that have quantitatively demonstrated that extreme events are on the increase. I am happy to provide links on another thread.

    You claims to consider yourself a researcher, but you have not cited any publications from reputable journals to back up your claims. That is not how science works.

    It is very easy to convince yourself that here is not a problem when you seek out extreme events at selected locations, but as I said earlier you have to consider the body of evidence form around the globe, it is called AGW after all. For example, last year 19 countries set all time record highs, compared to only one all-time record low, not surprisingly 2010 was tied for the warmest year on record, despite a prolonged solar minimum and the onset of a strong La Nina.

    "As I stated earlier I think it is on topic as it explains why I am not embracing the AGW view of future disaster."

    Sorry but that line of thinking is not only unscientific, but foolhardy. Do not forget that AGW is very much about where we are heading should we continue to be myopic and complacent regarding the consequences of doubling or trebling CO2. We have more than enough evidence now to know that we are facing some very difficult times ahead should we continue on this path. The prudent course of action is to not deny the facts and to take action in reducing GHG emissions. Bizarre that some would like to wait until it is too late to take action, just like in the video I showed @28.

    "Consensus views of "experts" in their field have been overturned and wrong."
    But nobody has overturned the theory of AGW. Regardless, your claims about consensus are moot; what we have now with the science is consilience, which is much stronger than consensus alone.

    You can continue to seek out events to convince yourself that AGW is not an issue, but doing so is just reinforcing your denial.

    "Historical data calls into question AGW climate change"

    No it doesn't.
  • Hockey stick is broken

    Albatross at 13:57 PM on 17 May, 2011


    Bud seems to be cherry-picking papers from the NIPCC's "Prudent Path" misinformation document. If so, he can keep at this for some time....

    Also, in the face of evidence to the contrary of his beliefs the "skeptics" just keeps forging ahead, mostly ignoring the inconvenient evidence. At this point one has to wonder whether the person is a "skeptics" or someone in denial about AGW.

    There are more Hockey Sticks out there than can be used by a NHL team, some generated using independent data not used in the original HS graph.

    e @85, good catch!
  • More Carbon Dioxide is not necessarily good for plants.

    Marcus at 09:20 AM on 19 April, 2011

    Back to the issue at hand-in spite of all the hand-waving & obfuscation being done by John D, BP & Luke, the fact remains that attempts to claim that enriched CO2 will be beneficial for agriculture are overly simplistic-as they ignore all the other negative impacts that might well result from either enriched CO2 directly, or from changes in hydrology & temperature that will result. These facts are backed up even by the results of the FACE trials in which they place so much faith-even though said trials do little to simulate expected changes in temperature & hydrology. Drops in nutrition, resistance to insect pests & increased soil-borne pathogens have all been shown to occur under eCO2 *alone*-which will almost certainly have a negative impact on crop yields & increase the cost of cropping for farmers. Certainly, just the known dangers to agriculture posed by increasing CO2 emissions should be sufficient to make us want to pursue a more prudent approach to the burning of fossil fuels. In Denial World, however, the risks are entirely worth it if it means a continued reliance on fossil fuels.
  • More Carbon Dioxide is not necessarily good for plants.

    Albatross at 04:15 AM on 19 April, 2011

    JohnD @128,

    Yes, BP did grab those section titles from the paper-- but he did not provide full context and did not draw people's attention to the other key (negative) findings made by the authors. It is unfortunate that that BP and now you intent on not being true to the primary conclusions of the paper. They are optimistic only if they can figure out why the plants are not responding favourably to elevated CO2 levels-- maybe b/c they have not had time to adapt to those levels to take advantage...who knows...they don't seem to know.

    I could be wrong, but I think that you would be hard pressed o find a lead author on the paper who thinks that continuing wit BAU is acceptable in view of the evidence.

    Again, not all the lessons point to a negative outcome (that is also stated in the IPCC), at least when viewed individually, but this paragraph from the paper under discussion should be cause for concern for those who are prudent and risk averse:

    "More broadly, the stimulation of seed yield in response to growth in elevated [CO2] is ∼50% lower in FACE experiments than in enclosure studies for the world's four most important crops (Long et al., 2006; Ainsworth, 2008; Ainsworth et al., 2008a)."

    Now let us look at some of Dr. Leakey's earlier work:

    SP Long, EA Ainsworth, ADB Leakey, J Nosberger & DR Ort (2006) Food for thought: Lower than expected crop yield stimulation with rising carbon dioxide concentrations. Science 312:1918-1921

    ADB Leakey, M Uribelarrea, EA Ainsworth, SL Naidu, A Rogers, DR Ort & SP Long (2006) Photosynthesis, productivity and yield of Zea mays are not affected by open-air elevation of CO2 concentration in the absence of drought. Plant Physiology 140:779-790

    Again, the prudent path here is to prepare for the worst rathe than wishful thinking that we can overcome the problems identified in the FACE experiments. And that means reducing GHG emissions.

    Sorry, but BP has scored quite the own goal, and your post is not helping him.

    It is not clear to me that the FACE experiments considered heat stress. I found no specific reference to the impact of heat stress in the body text.
  • It warmed just as fast in 1860-1880 and 1910-1940

    Albatross at 06:42 AM on 14 April, 2011


    Citing the much discredited Soon (that is but one of many examples) is not helping your case-- also, correlation is not causation. It seems that you have been gleaning papers from the "Prudent path" document which support your beliefs without being skeptical of their validity or credibility.

    As KE has noted,

    "Recent warming could not have happened without AGW; other forcings don't add up. "

    And you continue to misrepresent Dr. Box.

    I'm sorry, but several people now have very patiently explained the errs of your ways to you, yet you are not listening. You may not realize it, but by choosing to go down this road, you are essentially trolling, and not convincing anyone who has an understanding of these matters.
  • Arctic Ice March 2011

    Gilles at 15:04 PM on 7 April, 2011

    another related question : do you have a physical explanation of why the arctic sea ice extent doesn't show any significative variation in the 1900-1940 period, when the average global temperature shows a variation similar , although slightly smaller, to the current one ? and when, noticeably , proxies data show the maximal variation ? are boreal trees much more sensitive to some kind of temperatures that sea ice doesn't feel, and reciprocally?

    on other word, could you explain the big difference in the post-1900 behavior of these two curves ?

    and this one

  • 10 key climate indicators all point to the same finding: global warming is unmistakable

    JMurphy at 06:35 AM on 6 April, 2011

    With regard to the hope from RickyPockett that the trees will save us, a recent paper suggests things are not quite as simple as some would like to believe :

    Tree Growth and Fecundity Affected More by Climate Change Than Previously Thought

    The above link leads on to this one :

    Northern Forests Do Not Benefit from Lengthening Growing Season, Study Finds

    And there are plenty more from that link to suggest that perhaps we might be better to include tree-planting as part of an overall carbon-mitigation policy that has other plans which will be quicker and more reliable - such as shown in A Plan for 100% Renewable Energy by 2050, or Climate Emergency: Time to Slam on the Brakes, or A Real-World Example of Carbon Pricing Benefits Outweighing Costs, or The Prudent Path, or Carbon Pricing Costs vs. Benefits.
  • Hockey Stick Own Goal

    angusmac at 07:21 AM on 4 March, 2011

    Dana in your post, "Contrary to the Idsos' claims in the Prudent Path document, Ljungqvist says the following when combining his proxy reconstruction with recent instrumental temperature data:

    Since AD 1990, though, average temperatures in the extra-tropical Northern Hemisphere exceed those of any other warm decades the last two millennia, even the peak of the Medieval Warm Period."

    However, the actual statement by Ljungqvist (2010) (my emphasis added) appears to contradict your contention:

    "Substantial parts of the Roman Warm Period, from the first to the third centuries, and the Medieval Warm Period, from the ninth to the thirteenth centuries, seem to have equalled or exceeded the AD 1961-1990 mean temperature level in the extra-tropical Northern Hemisphere. Since AD 1990, though, average temperatures in the extra-tropical Northern Hemisphere exceed those of any other warm decades [of] the last two millennia, even the peak of the Medieval Warm Period, if we look at the instrumental temperature data spliced to the proxy reconstruction. However, this sharp rise in temperature compared to the magnitude of warmth in previous warm periods should be cautiously interpreted since it is not visible in the proxy reconstruction itself."

    The crux of Ljungqvist's statement which you have minimised, is that the, "instrumental data spliced to the proxy reconstruction" should be cautiously interpreted because the recent proxy data does not emulate the recent instrumental data. In a nutshell this is the "divergence problem."

    Re your comment that, "Indeed by plotting data along with Moberg et al. (2005), Mann et al. (2008), and the surface temperature record, we can confirm that the three reconstructions are very similar, and all show the peak of the MWP approximately 0.5°C cooler than today's temperatures (Figure 1)."

    Your statement that the MWP is 0.5 °C cooler than today is incorrect because you are comparing today's instrumental measurements with yesterday's proxies. To compare instrumental temperatures with proxy temperatures is physically and statistically wrong. The correct methodology is to compare today's proxies with previous proxies.

    I enclose Ljungqvist's original reconstruction in Figure A and I have removed the instrumental calibration data in Figure B for clarity.

    Figure A: Ljungqvist's Reconstruction with Instrumental Data that was used for Calibration

    Figure B: Ljungqvist's Reconstruction with Instrumental Data Deleted

    It is evident from Figures A and B that the MWP was at least as warm as the current warming period. Moberg (2005) and Mann (2008) show similar results when proxies are compared with proxies. Therefore, a correct interpretation is that all three reconstructions show that recent temperatures are similar to the MWP.

    From the foregoing, it would appear that the Prudent Path does support its claim that, if you compare proxies with proxies in your three reconstructions, the MWP was as hot as today.
  • Prudent Risk

    funglestrumpet at 07:28 AM on 26 February, 2011

    We cannot keep letting the ‘skeptics’ get away scot-free with such tactics. I suggest that we, too, should write to the US Congress, drawing their attention to the flaws in the arguments advanced by the ‘Prudent Path’ group by giving them a copy of this post.

    If the covering letter were to be signed by as many heavy-weight scientists as we can muster, it would obviously raise its profile. I think that we could get more out of this exercise if we offered the opportunity for them to raise any queries they have regarding the science contained in the post. If we explained that because there could be other members of Congress that might have similar points of concern, all queries will be in open forum, i.e. open to view by all, at .... (‘Congress Queries’? – only posts by members of Congress with replies by selected scientists.)

    These people are politicians, so they will be acutely aware that the media may well quote from this page in order to demonstrate an individual’s level of concern on the subject of Climate Change, a subject that will obviously be somewhere near the top of the agenda in the next round of elections to Congress. They would be foolish to appear uninterested, so will probably want to raise a question or two, if only for appearances. However, in raising any questions, they will have to make sure they understand them in case they get called to explain their concerns. Who knows, they might even come to see that ‘business as usual’ is not a realistic option! If we could raise enough interest now, it might even be a good media story before we get any replies. That would make the public turn to the ‘Skeptical Science’ website in order to check up on their member of Congress.

    Pity this ‘Prudent Path’ group didn’t write to all senior politicians everywhere – we could really spread the word then!
  • Hockey Stick Own Goal

    RobertS at 17:44 PM on 24 February, 2011

    "The NIPCC report is claiming that the IPCC sensitivity range is too high by a factor of 10, but the Idso Prudent Path document, by claiming that the MWP was as hot or hotter than today, is arguing that the IPCC sensitivity range is too low. "

    I don't quite understand this argument; I haven't seen any comprehensive reconstruction of net forcing over the past millennia, so it would seem to be a non-sequitur to state that the Idso's are necessarily arguing for a high climate sensitivity in arguing for a warm MWP.

    A MWP comparable in temperature to today is virtually impossible given the slew of millennial temperature reconstructions showing otherwise, and there is little indication of any dramatic changes in TSI or volcanic activity that could lead to such a warm MWP, but I'm not sure the latter proposition contradicts Idso's concurrent argument that CS is low.
  • Prudent Path Week

    RickG at 08:02 AM on 24 February, 2011

    Over the past several days I have participated in discussions over several threads as many of us have. I have seen many very well thought out and well presented arguments with the best intentions of helping all to understand the many aspects of climate science.

    Conversely, I have observed many posts that seem to ignore the most basic principles of physics as well as the many requests to look at data and citations presented to them.

    Many contrarian arguments have been thoroughly debunked by addressing specific questions and providing scientifically supporting evidence only to have the originator of the argument to return and say their question was not addressed.

    I know many posters here as well as I have become somewhat frustrated with the experience. For the past 24 hours I have only observed posts from the "Recent Comments" page and begin to look at this from a whole new prospective. No doubt it was difficult for me not to respond to some of the posts, but I begin to realize something very important.

    Anyone coming to this site seeking information and understanding with an open mind can easily see what is happening in the climate debate. One side presents only science with supporting evidence and references from the scientific community. The other side continously ignores the information being presented and even refuses to read any of the many articles presented on this site already addressing their questions. Any open minded person visiting this site whether they post or not can easily see this and separate the wheat from the chaff. In my opinion, I think the contrarians are their own worst enemy, if by nothing else, the tone presented in their own posts. As someone said in the "Meet The Denominator" thread, "you are the gift that keeps on giving".

    Understand my above comments apply only to those posters who have no intention of engaging in meaningful debate and not the true skeptics who wish to discuss and exchange ideas.

    Thank you John, Moderators and everyone connected with SkS for following the "proper path", rather than the "prudent path", with such a high quality site for us all to learn and enjoy.
  • Hockey Stick Own Goal

    Albatross at 06:36 AM on 24 February, 2011


    The fact remains that this comment made in the "Prudent path" misinformation document is not supported by the data and is demonstrably false:

    "it was just as warm as, or even warmer than, it has been recently during both the Roman and Medieval Warm Periods"

    That statement of course does not suggest anything about how much more warming we will very likely experience in the coming decades-- it is thus also a red herring.

    Also, the fact remains that the overwhelming evidence points to a climate sensitivity near +3 K for doubling CO2 and taking into account feedbacks.
  • Hockey Stick Own Goal

    MichaelM at 09:20 AM on 23 February, 2011

    "In their Prudent Path document, Craig and Sherwood Idso argue ..."
  • Hockey Stick Own Goal

    Albatross at 04:14 AM on 23 February, 2011

    Dana, good work. I was dumbfounded when I looked at page 10 of the Prudent path document-- they did not include the temperature data from the observational record-- that is totally misleading, because the end date for the Ljungqvist reconstruction was around 1990. Is that end date correct?
  • Prudent Path Week

    Bern at 14:42 PM on 21 February, 2011

    Chemist1 @ 16: I haven't read through that paper yet (and I suspect the statistical discussions are beyond my skills in that area), but the site selection immediately leaps out at me as being very, well, odd for Australia. For comparison of precipitation, for example, 3 out of 4 sites in Australia are in the "red centre" - very sparsely populated areas which get very irregular rainfall. It seems very odd, considering the high density of good weather records in the rest of the country...

    @mod response at 15: thanks, but I was mostly commenting on the fact that there doesn't appear to be a handy link to those graphics anywhere on the standard page layout - I've previously found it by searching for the blog posts that mention it.

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