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Comments 22701 to 22750:

  1. New study undercuts favorite climate myth ‘more CO2 is good for plants’

    martin @6, @11, and @24:

    1)  Song, Wang and Tang (2016), to which you linked @6 above states:

    "The rate at which the global average surface air temperature (Ts) increases has slowed down during the past few decades1. This so-called hiatus, pause, or slowdown of global warming has inspired investigations into its potential causes worldwide1,2. Although some researchers doubted the existence of a global warming hiatus because of coverage bias3,4, artificial inconsistency5, and a change point analysis of instrumental Ts records6, it is now accepted that a recent warming deceleration can be clearly observed1. There are two primary hypotheses to explain the recent slowdown of the upward trend in Ts7. Both hypotheses attempt to explain the contradiction between the trendless Ts variation and the intensifying anthropogenic greenhouse effect resulting from the steadily increasing emission of greenhouse gases (GHGs)."

    a) Taking an analogy from formula 1 racing, if a driver finds themself in the unfortunate position of needing to conserve fuel, commentators will be universal in saying that they have slowed down.  They will not say that the driver has "paused", or "taken a hiatus".  This universality of expression will be because they are competent speakers of the English language, in which a "pause" or "hiatus" requires "a short period in which something such as a sound or an activity is stopped before starting again".  As the period 1998-2013 has not been a period with a stop in the increase in GMST, the terms "pause" and "hiatus" are false descriptors of the phenomenon.  They have come into usage because of deliberate attempts of climate change deniers to deceive, and intruded into the scientific literature as the result of climate scientists not being careful with their language.

    b)  Whether or not there is a reduction in the Global Mean Surface Temperature (GMST) trend from 1998-2013 relative to the trend from 1975-1998 depends on what you count as noise.  The trend estimate is, of course, the best estimate of the linear trajectory of the data on the assumption of no noise.  It is because of the no noise assumption that it makes sense to tell people to pay attention to the trend rather than the variation in projecting future states.  That being the case, whether or not there has been a "slowdown" depends in part on what is counted as noise.  If you are interested in likely change in the mean climatological state, noise includes volcanoes, short term oceanic fluctuations such as ENSO, etc.  If we are only interested in the specific trajectory of GMST, then noise includes measurement error, including error due to incomplete and/or uneven distribution of meteorological stations.  Whether or not you consider there to have been a slowdown may depend crucially on which you are interested in, and that has varied between different studies of the issue.  In general, while there was reason to think there was a reduction in the trend in GMST (considered as such) from 1998 to 2013, there has been no substantive evidence of a reduction in the rate of change of the mean climatological state with regard to GMST over the same period.  In fact, as several studies have shown, quite the contrary.

    c)  Song et al cite Fyfe et al (2016) as proof that there has in fact been a "hiatus" (strictly, slow down) in GMST, and as establishing a consensus on that point.  However, only one author of Fyfe et al (ie, Ed Hawkins) was also an author of one of the papers Song et al cite as being shown to be obsolete by Fyfe et al.  Clearly the authors of those papers may still disagree on that point; and equally clearly Song et al's claim that Fyfe et al's conclusions are now "accepted" is not evidenced merely by citing Fyfe et al.

    d)  Finally, on this point, Song et al's claim that the period between 1998 and 2013 (ie, the period discusses in Trenberth (2015), which they cite) is "trendless" is clearly misleading.  Specifically the NOAA trend from 1975-1998 was 0.160 +/- 0.084 C per decade.  That from 1998-2013 was 0.086 +/- 0.148 C per decade.  While the 1998-2013 trend was clearly within error of a zero trend, it was in fact closer to, and within error of the 1975-1998 trend.  Therefore it is less accurate to call the trend "trendless" than it is to say that it was the same as that in the prior period.  In fact, neither claim should be made from that data if we are considering the trend in GMST alone (ie, considering measurement and coverage errors alone).  In contrast, if we are considering change in mean climatological state, we should note that the period 1975-1998 goes from the strongest La Nina event in the late twentieth century, to possibly the strongest El Nino event on record; and that 1998-2013 goes from that same El Nino to a La Nina (2011/12) that was as strong as that of 1974/75.  Both, therefore are perturbed from the trend in mean climatalogical state with regard to temperature, and in opposite directions.  The clear conclusion is that the trend in mean climatalogical state is unlikely to have been perturbed over that period, and if so - by very little.

    To keep this in convenient post sizes, I will discuss the other, more interesting aspects of Song et al in another comment. 

  2. How climate science deniers can accept so many 'impossible things' all at once

    Red Baron @2

    I think the article is basically right. Small government free market ideologists are often climate change sceptics in my experience. Conservatives and Republicans do tend to be small government and against regulation. Remember Ronald Reagon?

    Of course they can also be hypocrites, and happy to subsidise things or support certain types of regulations when it suits. Your post has only really proven they are hypocrites.

    However I agree about oil subsidies. This is totally unjustified policy, as the oil industry does not need subsidies! And both Democrats and Republicans appear guilty of supporting these. As you say it’s too do with campaign financing and repaying favours and this is all most unfortunate.

  3. How climate science deniers can accept so many 'impossible things' all at once

    Because cutting GHG emissions requires interventions – such as regulation or increased taxation – that interfere with laissez-faire free-market economics, people whose identity and worldview centres around free markets are particularly challenged by the findings from climate science.

    Oh really? Fossil-fuel consumption subsidies worldwide amounted to $493 billion in 2014, with subsidies to oil products representing over half of the total. Those subsidies were over four-times the value of subsidies to renewable energy. That proves 2 things. 1 is that the whole "free market" thing is already a complete myth. 2 There is not necessarily any need for increased taxation. Just take the EXACT same subsidies already being spent and put them on renewables instead. Theorectically if you were a die hard "free market" guy you could even just lower taxation by eliminating Fossil-fuel consumption subsidies. Lower taxes to promote renewable energy seems quite an easy sell to Conservatives IMHO. It's way better than subsidizing fossil fuels, so should go over pretty well with Liberals too.

    The mistake of course being the premise is wrong. It's got nothing to do with conservative or liberal. It only happens because corrupt politicians need to repay the campaign contributions they received. quid pro quo.

    It is true that conservatives SELL  this as their attempts to keep taxes and regulations down. The liberals SELL this as a needed increase in taxation and regulation. The truth is it is EXACTLY the opposite. The ONLY  difference is which side of the aisle the spin doctors who write this kind of propaganda are working with. Liberals like to hear liberal slanted spins, and conservatives like to hear conservative slanted spins. Nothing more than confirmation bias from both sides.

  4. How climate science deniers can accept so many 'impossible things' all at once

    Good points. I have seen climate change sceptics make these contradictory arguments in books and articles, and they are dumbfounding.They either dont have the wit to see they are being contradictory, or they just don’t care. It’s war by throwing as much mud as possible hoping enough will stick.

    The basic climate scepticism may have various origins. As the article says, some people promote small government and are anti government regulation almost by instinct, and this possibly colours their views against emissions taxes etc, and so they try to discredit the science. I think their unconscious world view is colouring their immediate reactions to the science.

    However anti government regulation agendas have a political, business and ideological basis only. Economists mostly accept markets dont adequately self regulate, to protect the environment and that laws are needed. Even Nixon sensibly introduced environmental laws.

  5. Climate inertia

    Climate Noob @9, @5 above I discuss the differences between the Transient Climate Response (TCR), Equilibrium Climate Sensitivity (ECS), and Earth System Response (ESS).  I also have a detailed discussion of the likelihood estimates of the values of the ECS in the IPCC AR5.  Looking at it in detail is very interesting, for it shows that according to the IPCC the most likely result is an ECS below 3 C, and indeed that the most likely single value (mode) may be below 2 C.  That is important if you are prone to give in to councils of despair given the plethora of bad climate news around.

    Importantly, however, the mean values of the ECS estimate are almost certainly just above 3 C.  In cost benefit analysis, it is typically the mean value that is the best indicator of the likely cost of the scenario.  If costs increase more than linearly with increasing temperature, the best indicator in a cost benefit analysis woud be from values above the mean.  It is somewhat like Russian Roulette.  The most likely value from a single round of Russian Roulette is no bullet in the head, but that one in six chance of blowing your brains out pretty much always makes Russian Roulette a round of Russian Roulette a stupid play.  Likewise with global warming, the most likely result has a moderate ECS and a reasonable probability of moderate harm; but the significant (if small) probability of truly catastrophic harms means if we are smart, we don't play the game, ie, we cease GHG emissions as quickly as is technically and economically feasible.

    What distinguishs the ECS estimates of the more reasonable climate skeptics is that they have a PDF which cuts of near 1 C as sharply as does the estimated IPCC PDFs, but also cuts of almost as sharply at or near 3 C.  That it, what distinguishes these skeptics is that they are far more certain of their result than are the IPCC.  That extra certainty is obtained by excluding a large number of emperical methods of determining the ECS, including all comparisons with past times, all assessments of modern temperatures except those by energy balance models; and of course, by excluding the non-emperical estimates based on the climate models.  In addition, they seem to use a number of controversial assumptions, all of which reduce the estimated ECS.  In short, what distinguishes them is a biased dogmatism most noteworthy for the quantity of information excluded from their estimates.   

  6. Climate change doubled the chances of Louisiana heavy rains, scientists warn

    BilB is right that moist air is lighter less dense than dry air (because water vapor is less dense than air). The chain of processes (see alanbetts.com) goes like this: Warmer ocean, a lot more evaporation. Moister air goes up into clouds and more condensation releases more heat which intensifies storms and sucks in more moist air; and gives more rainfall. The other important part is that water vapor is a powerful greenhouse gas (because there is so much of it) and the longwave radiative effect of more water vapor roughly triples the effect of increasing CO2.

  7. New study undercuts favorite climate myth ‘more CO2 is good for plants’

    Sorry, my links got lost. I have added them here. Please delete my post #24.

    @Moderator My references were all to the same single non-paywalled paper. I have added further links to papers below.

    @RedBaron #12 Your quite right, my quote from the paper’s introduction does indeed refer to a slowdown of global warming.

    It also contradicts researchers like Cowtan & Way and Lewandowsksy who doubted the existence of a hiatus due to coverage bias, or Karl due to an artificial bias, or Cahill & Rahmsdorf using change point analysis.

    My first post stating that CO2 has had only an imperceptible effect on temperature was incorrect.
    As I wrote in my second post, the paper shows, in figure 2, the two parameters Gaa (atmospheric greenhouse effect anomaly) and Gsa (surface greenhouse effect anomaly) have remained essentially flat since 1992. And yes, the authors do explain this by asserting that the heat has been transferred to the oceans.

    My main point is supported by the paper’s introduction. There is disagreement among scientists about whether there has been a hiatus/ slowdown or not.

  8. 375 top scientists warn of 'real, serious, immediate' climate threat

    @nigelj,

     Yeah, I must agree. Not every part of the Crunchy Con Manifesto is compelling to me either. I just threw that out there to show there is some opposition to the current crop of corrupt politicians leading the conservative side of the aisle.

    In my opinion those politicians are primarily engaged in molding their constituents views on AGW  and important environmental issues with propaganda, rather than actually representing their constituents views. And BTW, I don't think this phenomenon of attempting to influence rather than reflect is limited to the conservative side either.

  9. 375 top scientists warn of 'real, serious, immediate' climate threat

    Red Baron @2

    Your conservative agenda is a big step forwards but still not totally compelling to me. (Disclosure of bias, - I lean liberal). For example "6 Small, Local, Old, and Particular are almost always better than Big, Global, New, and Abstract." It's hard to see on what logical basis anyone can really argue this.

    On what basis is old mostly better than new? Are smartphones a bad thing? It would also suggest opposition to free trade agreements, or other global alliances, and I wasn’t aware conservatives opposed those.

    How about small and local and traditional is sometimes good, and big and global is sometimes good, and let logic and evidence determine which should prevail in specific circumstances. I would also say if we structure policies in a way that is generally as fair as possible to everyone, humanity will go a long way.

  10. 375 top scientists warn of 'real, serious, immediate' climate threat

    I admire the strong and courageous stand this group of scientists have taken in speaking out. Generally scientists should of course be restrained, but there are cases where it would be absurd to stay silent.

    Every value system has exceptional circumstances. I think its a kind of a whistle blowing issue. Trump is so out of line something had to be said for the sake of humanity as a whole.

  11. New study undercuts favorite climate myth ‘more CO2 is good for plants’

    Moderator,

     Yes that's it. Thanks.

  12. 375 top scientists warn of 'real, serious, immediate' climate threat

    John, Why didn't you sign this? If they didn't ask for your signature, why not? Same question for all the many other climatologists out there (?). There is a lot of power-of-voice to having a large group of scientists speak out in a strongly worded letter like this. Routine letters like this (once every 6-12 months) with as many signatures as possible would be a good thing to continue.

  13. New study undercuts favorite climate myth ‘more CO2 is good for plants’

    @21 John Hartz,

     I am hitting a paywall to the actual Science study. So once again difficult to really address it properly. But going by the description in the Washington Post it appears as if they have found a flaw in the Roth C mathematical model that most climate scientists are using to measure and predict soil carbon. I am basing that opinion on this from the Washing Post:

    This is important, because carbon sequestration — basically, the uptake of carbon by the soil — doesn’t just happen instantaneously. First, carbon dioxide is taken up by trees and other vegetation, who need it to survive. When they die, they eventually break down and the carbon they contain goes into the soil. Older carbon in the soil implies that this process takes a longer time.

    It is no surprise to me that the Roth C model is even more flawed than previously thought. See that description found in the Washing Post is not how soils primarily absorb and lock carbon. Yes soils do form that way but extremely slowly. That's why forest soils in general are so shallow, low in carbon, and poor in nutrients compared to grassland/savanna soils.

    I posted about this a couple weeks ago on another SkepticalScience thread with good references. So rather than keep repeating myself, I'll just say that it has nothing to do with the estimates I am using regarding regenerative ag. And it actually is well known that once sequestered, soil carbon does last in the range of thousands of years rather than hundreds of years. (unless disturbed of course) Another case of Science playing catch up; at least 10 years behind what's already well known by many farmers in the field. Regenerative Ag primarily sequesters carbon and restores soil health by "The liquid carbon biochemical pathway", not inputs of labile carbon on the surface and O-horizons.

    Again though, without actually accessing the paper, hard to be sure exactly.

    Moderator Response:

    [PS] Would I be right in guessing that the comment you are referring to with the science links is this one? There is a unique link to a comment via the date on top right of a comment.

    Interesting discussion by way. Makes a change from rebutting would-be Galileos.

  14. New study undercuts favorite climate myth ‘more CO2 is good for plants’

    RedBaron: Thanks for the clarification.

    Here's another recent article about new research results that you may want to peruse: 

    The Earth is soaking up less carbon than we thought — which could make it warm up even faster by Chelsea Harvey, Energy & Environment, Washington Post, Sep 22, 2016

  15. New study undercuts favorite climate myth ‘more CO2 is good for plants’

    @19 John Hartz,

     Absolutely we need technological fixes in the energy sector. That's the emissions side. Regenerative agriculture actually reduces the emissions side too. But holding atmospheric CO2 to ~400 ppm +/- is not enough. To solve AGW I believe the evidence is pretty clear we actually need to rapidly drawdown atmospheric CO2. I have seen estimates around 300 ppm. Maybe more maybe less, but certainly less than 400 ppm.

    So yes. It would be a fools errand to be throwing gasoline on the fire at the same time you are trying to hose it down with water.  Goes to the ancient wisdom that a house divided against itself can not stand.

    We need to actually be cooperating in this effort, changing both the energy sectors and the agricultural sectors, since either change alone without the help of the other is very likely to fail.

  16. New study undercuts favorite climate myth ‘more CO2 is good for plants’

    Red Baron: You state,

    The good news being the whole problem goes away when we restructure production models and use regenerative agriculture to produce our food instead. Not only the vulnerability, but AGW itself.

    Are you putting all of your eggs into the basket of "regenerative agriculture"?  What about reducing the amount of fossil fuels being consumed to produce energy and to provide transportation?

  17. New study undercuts favorite climate myth ‘more CO2 is good for plants’

    @17 John Hartz,

     Thanks for that. The press release is almost useless, but I feel a lot better about the paper now that I had a chance to read it. Although the conclusions they make should frighten everyone on the planet. They really are showing with a decent model what many have most feared, the doomsday scenario collapse of worldwide agriculture, but potentially accelorated as a result of climate change. They don't outright say it because they masked much of what is going on in our agricultural soils. But they did get correct the limitations of currently used technologies and production models to meet future demand and conclude correctly that in the future to offset this we will need to open up even more new areas. (The doomsday scenario)

    Our results not only improve confidence in the projections of vulnerability of the yields of cereal crops to climate change, but also point towards needs for knowledge on new technologies, and changes in management and genotypes.

    That is probably the highlight of the study. The only flaw there being the solution already exists. ie Stop overproducing grain in the first place and completely restucture the production models to regenerative systems. But yes, if we don't use that solution and keep to the course we are currently, there is a huge vulnerability.

    The good news being the whole problem goes away when we restructure production models and use regenerative agriculture to produce our food instead. Not only the vulnerability, but AGW itself.

  18. New study undercuts favorite climate myth ‘more CO2 is good for plants’

    RedBaron:

    My bad - I had inserted the wrong url into my post #15. The correct url has now been inserted in that post.

    The U of Birmingham article is a news release with the following appended to it:

    About the study:

    • Pugh et al. ‘Climate analogues suggest limited potential for intensification of production on current croplands under climate change’ Nature Communications (2016). DOI:10.1038/ncomms12608
    • Previous assessments of future food production under climate change have been based on process-based and empirical models, leading to a wide variation in both the magnitude and direction of effects. This research uses a data-driven approach instead, based on current estimates of maximum-attainable yields with existing technology, and climate analogues.
    • Between 1960 and 2000, global cereal production doubled, primarily through intensification of agriculture on current croplands and by the breeding of more productive crop varieties. It is projected that global food production needs to increase by another 60-110% by 2050; to keep up with anticipated increases in human population and changes in diet.
    • Current expectations are that changes in climate over the next century will tend to decrease yields at lower latitudes and increase yields at northern latitudes.
  19. Climate Bet for Charity, 2016 Update

    I see that Kiwithinker has adopted "the line indicating benchmark" in his latest posting, as per Tom Curtis @6.

    His latest posting is perhaps less optimistic than his June posting when he said "I’m guessing the green line will cross back under the red in five or six months as El Nino fades out and La Nina arrives." Including August's data, the 2010s are now further ahead than the 2000s have ever been since the start of the bet. And all indicators are suggesting that lead will increase in the short term. Indeed, to manage a 'crossing' by the end of the year to put the 2000s back in the front would now require 4 months averaging a negative anomaly. That's actually a pretty rare event these days. It has happened this century only in 2011 and 2008.

  20. 375 top scientists warn of 'real, serious, immediate' climate threat

    Unfortunately the solution isn't to attack the Republican party, but rather for the constituents of the Republican party to say enough is enough.

    There are rumblings. But so far no leader to rally behind. When your choices are bad, worse, terrible, or insanely ridiculous, you are forced to simply vote according to other aspects of a platform.

    A Crunchy Con Manifesto
    By Rod Dreher

    1 We are conservatives who stand outside the conservative mainstream; therefore, we can see things that matter more clearly.
    2 Modern conservatism has become too focused on money, power, and the accumulation of stuff, and insufficiently concerned with the content of our individual and social character.
    3 Big business deserves as much skepticism as big government.
    4 Culture is more important than politics and economics.
    5 A conservatism that does not practice restraint, humility, and good stewardship—especially of the natural world—is not fundamentally conservative.
    6 Small, Local, Old, and Particular are almost always better than Big, Global, New, and Abstract.
    7 Beauty is more important than efficiency.
    8 The relentlessness of media-driven pop culture deadens our senses to authentic truth, beauty, and wisdom.
    9 We share Russell Kirk’s conviction that “the institution most essential to conserve is the family.
    10 Politics and economics won’t save us; if our culture is to be saved at all, it will be by faithfully living by the Permanent Things, conserving these ancient moral truths in the choices we make in our everyday lives.

    Now if there actually was a crunchy conservative in the presidential race, he would likely win the election hands down. Personally I don't even think it would be close. Might even surpass Reagan's landslide. But a candidate that would give up the huge campaign money they would surely lose out on? Not going to happen. It would take someone as rich as Trump but about 100 IQ points smarter and actually sane.

  21. 375 top scientists warn of 'real, serious, immediate' climate threat

    It's simply impossible for us scientists to stay politically neutral (as James Hansen always wanted to stay) in such a farcical evironment as GOP & their 2016 presidential candidate have created.

  22. New study undercuts favorite climate myth ‘more CO2 is good for plants’

    @15 John,

     I wish I could find the link to the actual study and/or hypothesis and/or model they used. I have a whole lot of issues with statement like what that team of researchers made, but without actually seeing the assumptions that they made first, difficult to really comment. About 1/2 of what they base their conclusion on I agree with. About 1/2 is complete bollocks. For example: 

    Efforts to increase food production usually focus on closing the yield gap, i.e. minimising the difference between what could potentially be grown on a given area of land and what is actually harvested. Highly-developed countries already have a very small yield gap, so the negative effects of climate change on potential yield are likely to be felt more acutely in these areas.

    Read more at: http://phys.org/news/2016-09-climate-global-food-demand.html#jCp

     

    This is completely wrong. Industrialized countries have a huge yield gap of at least 50% or more simply due to the way we raise commodity grains to feed animals. It is a highly inefficient use of land. A forage/integrated system far outproduces the monocrop/CAFO model of production. It's not even close really. What often happens is conversion rates are used, and commodity grains do produce a high feed conversion rate. However the amount yields is a tiny % of total biomass produced, and that monocrop total biomass produced is a tiny % compared to perennial biomass production when comparing same to same. It is maybe 500 to 1000% difference or more. It's not even close. Since about 1/2 the cropland in highly developed countries is devoted to this very inefficient production model, and the rest of the land is not much better, the claim is completely false. So any conclusions drawn from that false premise also have no basis.

    Now some of their claims are spot on to be sure.  However, that's a big enough flaw to ruin the whole thing. 

    There is another flaw too.

    Food production takes up almost half of the planet's land surface and threatens to consume the fertile land that still remains, scientists warn. The global impact of farming on the environment is revealed in new maps, which show that 40 percent of the Earth's land is now given over to agriculture.

    By the time you subtract out mountains, swamps, rainforests and deserts etc. That doesn't leave much at all. Are we going to clear and plant the last few wilderness areas and national parks we have left? Will we subject them to mass "cides" like we already have on almost 1/2 the planets land surface too? That's a huge huge disaster in the making. You think it's bad now. That really could literally collapse the entire biosphere irreversably.

    That definately needs to be the road not  taken.

  23. Climate inertia

    Climate Noob:

    In the middle of the menu bar, just below the Skeptical Science masthead, is a link to "Comments". That will load a page that has all new comments on all threads/topics. Easy to see what people have been saying regardless of where it is. The number of new comments here each day is fairly small, so you should find what you want on the first page (or two, at most).

  24. Climate inertia

    Thanks TD, I'll take a look at those sources and see how his claims hold up.

     A question about posts:  Is there a web location to go to so I can keep track of comments I post in comment sections?  It took me a while to find this page again.  I've bookmarked it now, but is there something that directs me to my comments which have received replies?  I'm new to the site and I just don't know.

    Thanks again.

  25. The Climate Change Authority report: a dissenting view

    Mal Adapted - this discussion arose around the question of whether a carbon tax would encourage drilling. Tom's use of "wholesale" is really short hand for "1st point on the chain" which in your terminology is "producer". The point here is that producer gets no more income than before, so has no incentive to drill.

  26. New study undercuts favorite climate myth ‘more CO2 is good for plants’

    Recommended supplemental reading: 

    A team of researchers led by the University of Birmingham warns that without significant improvements in technology, global crop yields are likely to fall in the areas currently used for production of the world’s three major cereal crops, forcing production to move to new areas.

    Climate change means land use will need to change to keep up with global food demand, say scientists, University of Birmingham News, Sep 20, 2016

  27. The Climate Change Authority report: a dissenting view

    Tom Curtis #11, yes, there is more to say about appropriate design of a carbon tax.  I was narrowly addressing Michael Sweet's claim "The point of a carbon tax is to raise retail prices while wholesale prices remain the same." A carbon tax on fossil fuel producers at the source is intended to raise wholesale prices, which would raise retail prices as well.

  28. New study undercuts favorite climate myth ‘more CO2 is good for plants’

    Martin, the Song paper suggests the recent  "slowdown" is due to lots of la nina events since about 1998, and this has led to less cloud cover and thus a reduced greenhouse effect. This will swing to the opposite phase and may have already done this given the big el nino last year. Its a natural cycle influencing the underlying trend from CO2.

  29. New study undercuts favorite climate myth ‘more CO2 is good for plants’

    RedBaron@12.  One might expect that if an atmospheric heating deceleration since 1992 was caused by an ocean heating acceleration, we might see such a thing occurring in a graph of ocean heating: ocean heat content since 1950 

    I don't know if this is conclusive but it supports the argument.

  30. New study undercuts favorite climate myth ‘more CO2 is good for plants’

    Martin,

     You really have to read your own quotes a little better. Your own quote says quite clearly the rate of increase has slowed. It does not say "the trend is flat". It does not say "CO2 has had only an imperceptible effect". It also says surface temps and the whole paper discusses why the surface temp rate of increase has slowed, ie in this case they conclude it has warmed the ocean. Warming the ocean is not an imperceptable effect. I hate to put this to you bluntly. But the ocean is part of the globe. Thus while the rate of warming surface temps has not increased as much as the previous trends, global  warming  has continued to accelorate as expected.

  31. New study undercuts favorite climate myth ‘more CO2 is good for plants’

    In response to the moderator's questions, I would like to add a quote and also somewhat modify one of my statements.

    Regarding the term Hiatus

    “Introduction

    The rate at which the global average surface air temperature (Ts) increases has slowed down during the past few decades. This so-called hiatus, pause, or slowdown of global warming has inspired investigations into its potential causes worldwide. Although some researches doubted the existence of a global warming hiatus because of coverage bias, artificial inconsistency, and a change point analysis of instrumental Ts records, it is now accepted that a recent warming deceleration can be clearly observed.”

    Regarding "CO2 has had only an imperceptible effect on global warming"

    I would like to modify my statement to "has hardly influenced the greenhouse effect - as described in this paper - since 1992"

    The paper describes two greenhouse effect parameters Ga (atmosphere) and Gs (surface). Figure 2 shows the atmospheric greenhouse effect anomaly Gaa and the surface greenhouse effect anomaly Gsa. The trend is flat since 1992, although CO2 has increased since then.

    Moderator Response:

    [JH] Please clarify which paper(s) you are quoting from. If it is not the paper cited in the OP, please provide links to the paper(s) you are referencing. 

  32. New study undercuts favorite climate myth ‘more CO2 is good for plants’

    @9 Christian

    Correct, the CO2 fertilization effect is a valid observable empirically confirmed phenomenum. It is in fact what we term a stabilizing feedback in the labile (short) carbon cycle. The problem of course is that this stabilizing feedback is not large enough to offset emissions. Every climate model I have seen includes this feedback already. Climate deniers like to misuse this sort of data by cherry picking only feedbacks that appear to stabilize and ignore reinforcing feedbacks. Climate alarmists often do the opposite to claim we are all doomed.

    Reality is there are many reinforcing feedbacks and stabilizing feedbacks all interconnected in highly nuanced complex ways. But the NET result is increased atmospheric CO2 and manmade global warming.

    I have a problem with the study only because they failed to outright awknowledge that this particular grassland is already showing severe signs of degradation that have nothing to do with AGW. As it turns out this extremely degraded grassland is stressed even worse by AGW than a healthy grassland would. You have a dieing patient that shows signs of dieing faster when subjected to further stress. Is this news? Is this science? Do we learn anything new from it? Does it inform us in any way as to how a healthy grassland will respond?

    And BTW no, it does not have increased drought resistance. Quite the contrary. Those native perennial C4 grasses that were extirpated all have extremely deep and large root systems combined with heavy mycorrhizal symbiosis compared to the relatively shallow rooted invasive annual C3 grasses that are filling the niche. All these are far more important to drought resistance than any CO2 fert effect. That grassland undoubtably will have very poor drought resistance unlike a healthy grassland which is quite drought resistant. I personally think they used a very poor example to try and counter Rupert Murdock's ridiculous cherry picking. 

  33. Coordinator of UK Ocean Acidification Research Attacks The Spectator for 'Willfully Misleading' James Delingpole Column

    PS. The purpose of the Delingpole quote was to show his mentality. I didn't think it needed an explanation. I still don't think it does, actually.

    Moderator Response:

    [GT]

    Dennis. Accepted that was the intention of your comment, but I failed reading-tea-leaves 101. So adding some context to show whether you were supportive of Delingpole's position or not would have been helpful in understanding where you were coming from :-)

  34. New study undercuts favorite climate myth ‘more CO2 is good for plants’

    In defense of CO2, the paper does say that plants at Jasper Ridge appear less sensitive to CO2 than reported for other grasslands. So this study by itself reaffirms that CO2 doesn't always benefit grasslands growth, but leaves open the possibility that it mostly does so. Elevated CO2 also lowers the precipitation requirement for maximum NPP at Jasper Ridge, which should contribute to drought resilience.

    On a different note, isn't "CO2 is animal poop" about as biologically accurate as "CO2 is plant food"? :-)

  35. Coordinator of UK Ocean Acidification Research Attacks The Spectator for 'Willfully Misleading' James Delingpole Column

    http://www.breitbart.com/london/2016/09/14/massive-cover-exposed-lying-alarmists-rebranded-70s-global-cooling-scare-myth/

    JAMES DELINGPOLE14 Sep 2016

    "Scientization is, of course, what climate alarmists do all the time in order to support their bankrupt (but highly lucrative) thesis. Such is their brazen shamelessness, indeed, that you can’t help wondering whether – along with a worthless degree in something like environmental sciences from somewhere like the University of East Anglia – the main requirement for thriving in the world of climate science is the personality of a psychopath."

    Moderator Response:

    [PS] Thank you for taking the time to share with us.  Skeptical Science is a user forum wherein the science of climate change can be discussed from the standpoint of the science itself.  Ideology and politics get checked at the keyboard.

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

    With respect to your comment, a quote from a far-right media source citing complete baloney is simply sloganeering. Try a little skepticism about the article. It is also completely off-topic. Use the Search button on top left to find suitable articles. Review "They predicted an ice age in the 70s".  What your source fails to do is look at what science said in 70s versus the media.

    [GT]
    Comment reinstated. Poster clarified their intent (which would have been preferable from the start)

  36. Climate inertia

    Hi friends, I'm a noob when it comes to climate science, but I know enough to challenge "deniers" 99% of the time.  Recently I was talking with someone and they mentioned ECS, which I never heard of until now.  This is the only page I can find with ECS.  Based on talks with them, the overall argument is that "there are credible scientists who debate the ECS values.  The IPCC best guess is around 3.2, but 'Deniers' see the ECS as being significantly lower than 3.2. Likely 2.0 or under."

    It seems this person is claiming that whether AGW is dangerous or not, depends on this value, and this value is what credible skeptics are debating against.  I received this message from him and I cannot seem to find info to verify/reject what it asserts:
    (begin message)
    ECS science from what I know comes from 3 sources. Paleoclimatology, Modelling and observations. Observations seems to provide the lower end results, the others higher.

    ECS is basic physics of 1.1 and feedbacks which are estimated to be 0.4 to 3.4. The most important feedback is water vapor.

    This basic information has been the same for 60 years. So a low ECS has been around from the start and still persists.

    One link about low ECS is Link they provided to Judith Curry

    Your point about time is correct. Projections are based on 2 inputs. ECS and RCPs (CO2 estimations) Much of the new articles assume high for RCP (8.5), but that is extremely improbable.

    Correct about IPCC's estimation and the rationale for supporting it. However, observations are significantly lower than model means. It is hard to justify this after so long, and the divergence is getting worse not better (depending on data sets). This, plus failed basic tests of the hypothesis are the evidence deniers have. This evidence suggests that nature is playing a bigger role than most people think.

    Failed tests
    - lack of tropical hotspot, expected from warming
    - no warming in the antarctic (both poles should warm a lot more than other places)
    (You can find all sorts of rebuttal material, but the facts are pretty basic, these are traits that will happen is a warming world..... unless nature can overcome it).
    (end message)
    Any help on analyzing this, or sources to help a noob like me understand what it's all about and how to verify its claimes is much appreciated.
    During our discussions, I couldn't shake the feeling that there was something deceptive about this, so I want to learn more to make sure I'm not being taken for a ride.

    Moderator Response:

    [TD] Regarding the "tropic hotspot," see "There's no tropospheric hotspot." After reading the Intermediate tabbed pane, you might want to read the Advanced one.

    Regarding Antarctic warming, see "Natural forces overpowering Antarctic Peninsula warming."

    There is a lot on SkS about ECS, but here is a recent one: "Climate sensitivity is unlikely to be less than 2C, say scientists."

    [PS] You might also like to consider that to prove science wrong, you have to show observations contradict a projection that the science actually made. You might think Antarctica is "basic" but science doesnt. Please cite published predictions of equal warming. Ditto for your expectations of surface warming. Dont trust what deniers tell you about what science predicts - check it yourself.

  37. New study undercuts favorite climate myth ‘more CO2 is good for plants’

    martin@6: from your paper: "Our planet has become increasingly warm since the Industrial Revolution because of the increased GHG emissions... [but this]... rate... has slowed... in recent years... this hiatus is very likely a result of the occurrence of more La Niña events after 1992."  La Nina just means Earth is being more effective in pumping excess heat into her oceans.  Unfortunately, that doesn't make the excess heat 'go away' (1st law of thermo).   This graph shows that the IPCC climate models do, in some sense, expect this since 1992 (obviously with a little help from Pinatubo).  Again, the heat doesn't disappear: it may reappear Not as 'warming' but as 'melting' (of polar ice sheets).  If it does, I hardly think you will welcome the distinction.

  38. New study undercuts favorite climate myth ‘more CO2 is good for plants’

    martin @6 quick reply: the journal is "Scientific Reports", not "Nature". Your #1 and #2 statements do not appear to be supported by the paper.

  39. New study undercuts favorite climate myth ‘more CO2 is good for plants’

    Only slightly off-topic: A new paper published in Nature by Song, Wang and Tang shows that

    1. There has been a warming hiatus since 1992
    2. CO2 has had only an imperceptible effect on global warming

    Perhaps some comments from the experts?

    Moderator Response:

    [PS] Have you actually read the paper? I cant see anything in the conclusions that challenge the consensus opinion - rather it reinforces it. Perhaps you could quote the sections that you think constitutes an issue.

  40. New study undercuts favorite climate myth ‘more CO2 is good for plants’

    CO2 may or may not be "plant food" depending on the circumstances, but it it certainly is a "people poison". More and more evidence is gathering that indicates that CO2 has meaningful negative physiological effects at real-world levels. I am not sure why the climate hawk crowd is not making more hay out of studies like this.

    http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3548274/

    While more work and analysis needs to be done, my gut feeling is that these effects are on a similar order of magnitude in terms of cost to society as climate change and ocean acidification. We are effectly slowly smothering ourselves in "stuffy" air, and feeling like crap because of it. However, we don't notice the change because it is so gradual and we may just be assigning it to getting old.

  41. New study undercuts favorite climate myth ‘more CO2 is good for plants’

    Most importantly from the study, "Of 54 annual plant
    taxa in the JRGCE, 81% are nonnative to California, including
    all of the annual grasses; of 20 perennial taxa, 55% are native,
    including all perennial grass species except one. All of the plant
    species have the C3 photosynthesis pathway"

    You might miss this if you didn't know that as a rule perennial C4 grasses are your warm season grasses and perennial C3 grasses are your cool season grasses. No C4 species means of course warmer temps will have a more negative effect. That mix of non native C3 annuals filling the niche where C4 perennials should be present is a symptom of a very unhealthy grassland that will continue to degrade even worse under AGW.

    Seems the study came to the right conclusion that "it's more complicated that that" but for the wrong reasons because they really haven't understood very basic things about a grassland's complexity!

    All in all when science reaches a good conclusion but for the wrong reasons, it is junk science. This because it really doesn't inform us, add to our knowledge, or effectively predict anything.

  42. New study undercuts favorite climate myth ‘more CO2 is good for plants’

    At first, the 'carbon dioxide is plant food' argument seemed nonsensical to me.  I first ran across it with the infamous 'Oregon Petition'.  That's the one where 30,000 'scientists' claim CC is not a big deal because 'carbon dioxide is plant food'.  It seemed to me that something is a big deal if it buries Florida, so why the unusual comfort at the greening of an already green planet?  I finally realized what was going on: deniers think that those of us worried about CC are 'greenies', that is, tree-huggers.  They think we live in a Tee-Pee, commune with nature, and make beaded ornaments to sell at Farmers Markets where we buy our non-GMO, organic food.  Seen this way, its actually kind of cute: they are trying to 'meet us halfway' at where their propaganda insists we live: barefoot in a jungle or forest smoking pipe-weed with Gandalf.

  43. New study undercuts favorite climate myth ‘more CO2 is good for plants’

    Um, if you look at the Stanford paper, it seems to me that they did extend the growing season (look at the winter temps) and still got lower yields. This is 17 years worth of data covering the entire year.

    The above study is only for California grasslands but in terms of yield per acre, warmer winters are only going to be relevant to crops with multiple yields per season. Personally (ie I dont have a paper to back my uninformed opinion), I suspect impacts from hydrological cycle changes will dwarf effects of temperature and CO2 for many areas of the world.

  44. New study undercuts favorite climate myth ‘more CO2 is good for plants’

    I seem to recall that 25-28C is the optimum range for photosynthesis, so it makes sense that yeilds decrease at higher temperatrures above 30C.  

    Obviously, sunlight is essential for photosynthesis but I wonder to what extent the warmer winters will offset lower yeilds - by extending the growing season. This is something that isn't apparently adressed in the study.

  45. The Climate Change Authority report: a dissenting view

    Michael Sweet @18, yes people in America seem very anti tax, although the congress seem more opposed to tax than the population at large. There seems this strange divergence of views betweeen the population and republican congress in particular.

    I have never had this visceral dislike of taxation, although obviously I don't want astronomical taxes either. I come from a small country and it's hard to provide  sufficient services without taxation, because the private sector is just small.

    It's amazing the euphemisms people ahve to use to describe a tax. I partly agree with your dumping fee  analogy and its quite a good way to promote a carbon tax, however strictly speaking the idea is to stop the dumping completely rather than charge for it, and use the dividend for good works, presumably climate related.

    My ideal preference is that we should require companies to leave fossil fuels in the ground or firmly regulate these companies and other emitters. Of course this is probably  not politically sellable, so it leaves carbon taxes or an ets.

    A carbon tax just seems the most practical option.

    Another thing about emissions trading schemes. In theory these market driven schemes should encourage innovative solutions, but markets are notoriously slow to respond to price signals and change behaviour. I'm not sure we have the luxury of a slow system like this given the current global warming situation. A carbon tax combined with some selective regulation may provide faster results.

  46. The Climate Change Authority report: a dissenting view

    Nigelj,

    Sometimes people use the term "fee and dividend" instead of "tax" because so many people in the USA oppose any tax.  These two terms are equivalent (as long as the tax is accompanied by a dividend).  There is a fee at the dump to leave your trash, why shouldn't there be a fee to dump your trash in the atmosphere?

  47. Humidity is falling

    Specific humidity is increasing, relative humidity is expected to be approximately constant. The processes are somewhat complex however and are discussed in considerable detail with measurements in sections 2.5.4 and 2.5.5 of the AR5 WG1.

  48. The Climate Change Authority report: a dissenting view

    Tom Curtis @16,

    I agree public perceptions are important. The public may see a carbon tax as easy enough to understand, and reasonably transparent and upfront. They may see an ETS as complicated and involving some sort of rort by the corporate sector. 

    It’s interesting as my initial reaction was that a carbon tax might be unpopular as people are wary of new taxes, and that an ETS may be more publicly acceptable as its a market mechanism. Things often don’t turn out as expected.

    However I still see other more practical problems with an ETS. An ETS relies on trust, that companies have reduced emissions, met obligations, and forests are in fact planted. All this requires complex monitoring by government. A carbon tax is right upfront. Use of fossil fuels either decreases or it doesn’t. It all just seems easier to verify, or at least in a way that is easy for the public to comprehend.

    Of course an ETS could in theory lead to carbon sequestration rather than reducing fossil fuels. The scheme is kind of market driven and we cannot fully predict the ultimate solution or direction, only guess it. However I ‘m a born sceptic of market mechanisms ( I declare a bias there) and it just seems to me the obvious goal has to be to reduce fossil fuel use as directly as possible.

    However I’m not opposed to either scheme in principle, and the devil is in the detail of either approach.

  49. Researching climate change communication at George Mason University

    Congratulations, John.  Seems to me you are stepping into the lion's den.  I can't think of anyone better to help tame the deniers.

    Best Wishes and have Great Success.

    Marty Weirick

  50. 2016 SkS Weekly News Roundup #38

    The front page headline (on-line, I do not receive a hard copy) in the Los Angeles Times (one of the biggest newspapers in the USA) today was Trump's climate science denial clashes with reality of rising seas in Florida.  (link to article )  On-line it was accompanied by a large picture of a street in Florida submerged by high tide.  The article said that the biggest tides of the year are always in the fall.  Perhaps Trump will be required to explain the flooding.

    Headlines like this can only mean time for the deniers is running out.  We must hope that Trump does not get elected to continue the farce for four more years.

    Moderator Response:

    [JH] Thnk you for highlighting the LA Times article. I will post a link to it on the SkS Facebook page today.

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