Climate change is real – get used to it!


If you were getting poorer and poorer, but last year you got poorer a bit more slowly than in previous years – would you be happy?

The climate is warming – the 2000s were warmer than the 1990s (but not as much warmer as the 1990s were than the 1980s).

This is the link to today’s joint publication by the Royal Society and the National Academy of Sciences.  Do read it.  Have a look at Figure 1.

See coverage in Independent and Guardian (the Indie is better IMHO thanks to their excellent science editor Steve Connor).  The Daily Telegraph doesn’t appear to cover this global news, and the Daily Mail

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17 Replies to “Climate change is real – get used to it!”

  1. Steve, if you read Lovelock, it is already too late to do anything although I am not totally convinced by this.

    One thing I would suggest though is that we either start using the terms Climate Change/Shift or Atmospheric Warming rather than Global Warming. The climate sceptics are starting to pick holes in the smaller arguments (as I found out by talking about the subject away from this blog) by pointing out that northern Europe could become colder, for example and you know how the news media likes to distort these things. Having said that, I think we face an even bigger problem in that people argue corners even within Climate Change circles, which may be wholly human nature at work but is massively unhelpful.

  2. For heaven's sake Mike, of course climate change is real, climate has always been changing. The question is, what is the cause of climate change? There is no evidence that supports a human cause versus a plethora of natural causes. And please don't cite models as evidence; and appeals to authority, no matter who they are, cut no ice with me. I believe I am a rational thinking person, and much of what you write shows that you are too, so I am baffled by the stance you take. I remain unconvinced that humans have a significant effect on the global climate, but you seem totally convinced. For me to change my mind, I would want to see real measurements matching the models - which might take rather a long time, several decades at least. What would it take for you to change your mind?
    In the meantime, world governments are spending of the order of a billion dollars a day on an unproven issue. They are driving up the cost of energy, which prolongs the time that the poorest people on earth remain poor, 2 billion of them - thereby driving up their rate of procreation - one of the real problems that the planet faces.
    Wasting political and financial capital on climate change, other than on adaptation, just distracts us from the real issues facing the planet: poverty, corruption, population growth, habitat loss, over exploitation of the ocean, seabird by-catch, ocean pollution etc. etc..
    I could go on - but I will stop here.
    Cambridge, UK

    1. >For heaven's sake Mike, of course climate change is real, climate has always been changing.

      I hope you realise how illogical this is as an argument against the theory of anthropogenic climate change. Just because something has changed in the past doesn't mean humans are unable to influence it or that future change will be good or manageable for humans (or other species). Significant climate change in the past has also been accompanied by mass extinction events. Clearly life is not immune to climatic changes.

      > There is no evidence that supports a human cause versus a plethora of natural causes. And please don't cite models as evidence;

      If you think our understanding of the climate is based on models then you aren't very familiar with the science. Models are just tools to try and help understand the climate system and the speed and spatial distribution of the shorter term (centuries) changes. The evidence for the 'greenhouse effect' and anthropogenic climate change has nothing to do with models.

      The knowledge that human activity is driving climate changed is based on several things. Firstly physics and atmospheric chemistry which tell us that CO2 (and other greenhouse gases) in the atmosphere mean the surface is warmer than it would be if they were not present. Testing this effect with gases in a laboratory is trivial and well known and understood science for over a hundred years. Explaining how that plays out in the atmosphere is not so trivial but still not at all controversial. We would expect that adding CO2 will lower the temperature at which the earth radiates heat back out to space, creating an energy imbalance. This means we have an excellent physical basis to theorise that adding more CO2 will mean more energy accumulating in the climate system.

      We can confirm that this effect exists because we have been monitoring the earths climate for decades to centuries (depending which part of the system you are talking about) and we can see that temperatures have been rising at times when the other known external drivers of climate (changes in solar irradiance, volcanic activity, aerosols etc) can't have driven that change. The effects have persisted for long enough that they can't be explained by any known internal variability in the system (especially since pretty much all parts of the system that we can measure are warming: surface temperature, troposphere, surface oceans, deep oceans, the tropics, the poles - for it to be internal variability that energy would have to have come from somewhere). The only explanation we have that matches observations is that there is an accumulation of energy due to increased levels of greenhouse gasses.

      Knowing that this effect exists doesn't tell you how large the effect will be (climate sensitivity). We have records of historic (millions of years timescales) climate constructed from various proxy records which show us how the real earth has responded to changes to CO2 in the past and these confirm the idea that greenhouse gases can drive climate change and form a good basis for estimating climate sensitivity, without needing any models.

      > For me to change my mind, I would want to see real measurements matching the models - which might take rather a long time, several decades at least.

      You have to define what you mean by 'matching' here. I hope you will agree that it's unreasonable to expect climate models to closely match the weather day to day or year to year. When you see projections from models those are usually based on the averages of many runs, and the individual runs will often differ quite a lot from each other at a given point in time. One of the biggest reason for this is that the models don't attempt to predict short term internal variability like el nino (ENSO), partly because we don't know how to forecast ENSO more than about a year into the future with any level of accuracy. The models are run with random ENSO conditions, with the expectation that this will balance out and come to resemble reality over longer periods of time and over many runs (because we believe ENSO to be an internal fluctuation that balances itself out over significantly long timescales). This is also why climate models are not useful for making short term projections: the forcings that we know have the largest impact over short terms aren't something the models make any attempt to predict. A single model run of the last 10 years will probably not match the recorded temperatures because for example it might have run with several really strong el nino years, when in reality we have not had any really strong el nino seasons in that time. Of course there will be some models that got it right, by chance, and those runs can be fairly close to the observed climate.

      The early models have done surprisingly well really, considering how many aspects of the system they ignored. You can read about the evaluation of an older model here if you are sufficiently interested:

      >What would it take for you to change your mind?

      You final question is vague - somebody could change their mind about only part of the issue. For example, my position on equilibrium climate sensitivity (ECS) is pretty easy to change because the various lines of evidence we have (either from the paleo records or 20th century temperature records or climate models) all lead to ECS values with pretty big amount of uncertainty. At the moment I think sensitivity is very likely higher than 1.5 degrees per doubling of CO2, but it wouldn't be too hard to change my mind on that if there was significant new data. What would it take to change my mind about the idea that greenhouse gases lead to higher surface temperatures than an atmosphere without them? That would require an entirely new theory of how the climate and atmosphere works that somehow negates the basic physical processes of gases absorbing and emitting electromagnetic radiation and is also able to explain recent warming trends and is consistent with the paleo record (as well as surface temperatures that we can observe on other planets) and can be used to create models with decent predictive ability over multi-decade timescales. That is a pretty tough ask and nobody has come up with such an alternative theory that also fits the real world data and agrees with fundamental physics.

  3. "- get used to it!"

    Or what?

    The Green Party recently demanded a totalitarian purge of climate change sceptics from ministerial and advisory positions in government. A Labour Party Spokeswonk has confirmed that Thick Ed backs a similar ban. Can we expect dissenters to have their windows broken, to wear armbands, to have their arms tattoed?

    This quote is apt: "It has been the immediate aim of every fascist regime in history, to close down and stifle all dissenting opinions. The question of what, if anything, is to be done, who should do it, who should pay for it and when, if at all, it needs to be done are all legitimate questions. Science is never settled - if it is ever claimed to be, then it is not science."

    1. "Can we expect dissenters to have their windows broken, to wear armbands, to have their arms tattoed?"

      Mr Newell rejects arguments based on the "appeal to authority" - fair enough. I don't think the appeal to victim-hood is any more convincing. You are expressing your views quite freely here, Filbert. There seems to be no shortage of people prominently expressing 'climate sceptic' views on the BBC and elsewhere so it is somewhat histrionic to start talking about tatoos and armbands (and possibly a little offensive to people who really underwent such oppression).

      1. "… somewhat histrionic"
        You might use "histrionic" – I might use "rhetorical". When NYT has cartoons showing icicles being used as "self-destruct sabers for despatching climate-change deniers" – see that d-word connection in use again? – and Prof Naomi Oreskes suggests Racketeer Influenced Criminal Organisation prosecution for climate sceptics, I think it is legitimate to draw attention to this and I hope people who really underwent such oppression would be first in line to counter such an offensive trend.

  4. I am not sure I should reply to someone who replies anonymously with the name "J". I tried to keep my original comment brief, so may have been open to over simplification. If you actually read the second section of the Royal Society statement,"How do scientists know that recent climate change is largely caused by human activities?" then it is pretty limp, patronising, appeals to authority and doesn't come close to changing the mind of someone who is sceptical. Pretty disappointing stuff really. I am prepared to be convinced that CO2 causes dangerous warming if I hear a reasoned explanation. To be brief, sure, CO2 causes warming, but there is no mention of the uncertainty of cloud feedback - do clouds have a positive or negative feedback - no one knows.
    In the meantime, I am 100% certain that policies invoked to try to stop global warming are extremely dangerous both for the environment and for humans, especially the poor - these policies will kill far more people than the Nazi's ever killed, so please don't call me a denier.

  5. "The evidence for the 'greenhouse effect' and anthropogenic climate change has nothing to do with models."

    The models have been used to project future global temperature and its implications, and policy has been driven by them. The models did not predict the current plateau in temperature that started nearly two decades ago – if the models are wrong, then so are the policies they are driving. And it is not unreasonable to expect climate models to predict the global temperature year to year – given the cost to taxpayers. I want better value for my money (a theme familiar to this blog) – or I want it back.

    There has been no corresponding plateau in atmospheric CO2 – and until recently Climastrologists refused to acknowledge the divergence. Now there is an unseemly scramble to publish excuses for the divergence which formerly did not exist. The RS/NAS offering – self-published, but subject to Pal Review – has been described as a sedative for those agitated sheep nervously eyeing the exit gate. It is interesting that J mentions ECS. The RS/NAS report doesn't – which is odd, given the prominence of constant reference to it by parrots. But to say of the current trend of climate change "we can't explain it any other way" looks pretty much like use of the principle of exclusion, a hole which Darwin fell into. Fortunately there are many researchers worldwide who are still working on climate drivers other than CO2 and guess what? – the more they look, the more they find. Let's hope their funding doesn't get withdrawn for discovering inconvenient truths.

    As Dick Newell notes, world governments are spending of the order of a billion dollars a day – possibly even squillions but who knows? Suffice it to say that this political response guarantees a deficit of funding for adaptation measures that are known to work – you can't spend the same money twice, once it's gone on "a corrupt scramble for climate pork" (think carbon trading, wind energy subsidies, biofuels). It's about time some climate realism took hold – the futility of attempts to reduce UK GHG emissions while India and China (and Germany) et al press on with their expansion of coal- or lignite-fired energy generation must be obvious even to Thick Ed and Dopey Davey. Or maybe …?

    So adaptation should be the way ahead. The effects of climate change, whatever its causes, are going to be the same old same old – land use changes, floods, disease, poverty, coastal erosion, disease, no trains to Torquay. These are effects we can deal with. Dick Newell is right – wasted effort on emissions reduction just weakens our economy, leaving us less able to adapt to the real issues.

    Yours pseudonymously, etc

  6. Mr Newell
    re your concerns over clouds and feedback. Well, this is becoming the last refuge of those who still don't accept the blindingly obvious.

    It hinges on the fact that there is still some uncertainty in the climate models to how clouds behave in a warming climate and that the variation in climate sensitivity is mostly down to differences in cloud feedbacks, in particular low-level clouds.

    The argument is that low-level cloud cover will increase on a warming planet, so causing increases in the albedo of the Earth. The idea is that this "off-sets" a greater greenhouse effect and keeps warming to lower, safer levels

    There is - not surprisingly - a lot of research going on in this area and results are increasingly showing that the evidence is increasing all the time against clouds having a strongly negative feedback and for a significantly positive effect. The sensitivity of climate is also being shown not to be low either and the very latest research (from 2014 ) has found that low climate sensitivity models have been inconsistent with the observations. Simply, they presumed water vapor is drawn up to higher levels of the atmosphere to form clouds but warming of the lower atmosphere does the opposite and draws water away from higher up and the amount of cloud formation there gets smaller. This reduction in cloud leads therefore to greater warming - a positive feedback.

    To go into further detail is beyond the scope of a blogpost but there's a wealth of information out there, especially from the scientists who write the papers.

    The final comment of Mr Newell's isn't deserving of a reply and shows his mindset as much as anything else.

    As an aside, I'd be interested to know if cloud feedbacks were Mr Newell's main argument against anthropogenic climate change 5 years ago.

  7. Mr Cobb

    You also seem to have a very poor grasp of climate science and don't question enough of what you are told.

    I have absolutely no idea what evidence you have that climate models are not reliable? Maybe you will link to some peer-reviewed work that explain why they are not fit-for-purpose?

    Long-term climate models have been proved to make accurate predictions. It is well-known that models successfully predicted the climatic response after Mt Pinatubo erupted. They have also predicted other effects - also confirmed by observation - such as increased warming in the Arctic and over land, greater warming at night and cooling in the stratosphere

    In actual fact the models are starting to appear to be conservative in their predictions.

    Notably in terms of sea-level rise, the models are actually understating the problem and observations arenow at the upper range of projections and threre are other examples of the models being too too conservative

    And remember that the models are getting better and better all the time as they are refined and fine-tuned. It is unlikely that real world observations will be throwing us any curve balls in the future

    Our models have predicted a lot what we are now seeing and have empirical evidence for.

    I would also be interested to know if Mr Cobb was as accepting a few years ago of the climate changes that were predicted by climatologists, as he seems to be now. He just thinks it's natural, is all.

    1. My grasp of climate science is perfectly adequate for my needs, thanks.

      I am frequently told that I question far too much. In part this was inculcated while an undergraduate. “Is zis true?” was the basis for learning by analysis of research so questioning whatever I am told is something I have almost no control over. The other part is concerned with duck recognition. I am not an expert on ducks – I am happy to leave that to others. Nevertheless I am confident that if on examination a bird looks, sounds and walks like a duck- then it is a duck of some persuasion. This approach also works with lemons.

      With regard to the tone of patronizing superiority in your posts to both myself and Dick Newell, I won’t be spending time answering your partial copy and paste jobs from Skeptical Science. Plagiarism is lazy – write your own stuff, or put it in quotes.

      1. Mr Cobb

        Skeptical Science presents things in ways that are suitable for this type of discussion. There is little point in me engaging on a more scientific level as discussions quickly become tiresome and sidetracked. Best to stick to the basics and the underlying physics and chemistry. I have actually simplified the stuff a great deal anyway. It is always best to use what climatologists are saying rather than cobble together your own "theories", as people who work on climate change at an advanced level every day of their lives are actually worth listening too.

        If you have any issues with points of substance or you see anything that you think is not factually correct, then please reply and I will be happy to discuss things further.

        In terms of the current pause in warming that you mention, it should be remembered that the past decade was warmer than the previous decade which in turn was warmer than the decade preceeding that. And that 30-year-period is something like the warmest 30-year-period for 1400 years. The current decade is looking like it be even warmer than the last.

  8. I am not going to contribute more to this, I would just like to thank those who responded both negatively and positively. It is rare to see a blog with both sides of the argument presented.
    I would just like to apologise to Mark for addressing him as 'Mike' in my first post


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