Emma Thompson

Emma Thompson’s interview on newsnight has caused a bit of a Twitter storm because she got some things wrong. For example she said

if they take out of the earth all the oil they want to take out, you look at the science – our temperature will rise 4 degrees Celsius by 2030, and that’s not sustainable.

Well, this is clearly wrong. Our temperatures will almost certainly not rise by 4 degrees Celsius by 2030, but she did at least get right that how much we burn will determine how much we warm.

She also made strong claims about refugee crisis

Our refugee crisis – which, let me tell you, if we allow climate change to go on as it’s going, the refugee crisis we have at the moment will look like a tea party, compared to what’s going to happen in a few years’ time. Because if we allow climate change to continue, there are going to be entire swathes of the Earth that will become uninhabitable, and where are those people going to go? Where do we think they’re going to go? We’re looking at a humanitarian disaster of proportions we simply can’t imagine.

To make parts of the world uninhabitable would probably require wet bulbs temperature rising by about 4oC, which would imply a rise in global average surface temperature of around 7oC. This is possible if we continue along a high emission pathway, but I would hope that we won’t actually do so, and such temperature changes would likely be beyond 2100 if we did. Implying that this could happen in a a few years time is a huge exaggeration.

However, climate change does present risks, could lead to changes that will make some regions less able to support their populations than they are today, and could result in the movement of a large number of people. Even though climate change may have played an insignificant role in the current crisis (and it may well have played some kind of role), doesn’t mean that we shouldn’t be considering how we might deal with such a situation in the future, if climate change does force large numbers of people to relocate.

Okay, so Emma Thompson said some things that were completely wrong, and others that were exaggerating what we actually expect. Would be much better if she was more informed and more careful in what she said. There is no need to exaggerate. It’s serious enough without having to do so. It’s indeed not great that Emma Thompson gets a platform and gets things wrong. All the usual suspects are, of course, crowing about this and pointing out all the people who’ve said she was wrong. Fine, she was indeed wrong in a number of places.

However, here’s the big difference between Emma Thompson getting something wrong, and say – for example – Christopher Booker or Matt Ridley getting something wrong. When someone like Emma Thompson gets something wrong, you won’t easily find people promoting it. Typically – as has happened here – people point out the errors and accept that those who speak publicly about this should make sure that they’re sufficiently informed. When someone like Booker, or Ridley, gets something wrong, it gets promoted on various denialist blogs as highlighting problems with climate science.

The only positive from this is that it’s quite likely that – despite her errors – Emma Thompson will be remembered as someone who tried to highlight an important issue that we’re not taking sufficiently seriously, while Andrew Montford will remembered as someone who spread misinformation and doubt. Additionally, I would expect Emma Thompson to correct these errors in future, while Andrew Montford will continue to repeat his, over and over again.

Posted in Climate change, Gavin Schmidt, Global warming, Science | Tagged , , , , | 11 Comments

You can’t negotiate with Physics

In the comments on my previous post Rachel mentioned a recent article by Bill McKibben called we can’t negotiate over the physics of climate change. Given that he makes an argument that’s similar to what I’ve said myself, I should probably like it. However, I think he kind of fluffs it a bit.

When discussing drilling in the Arctic McKibben says

They think the relevant negotiation is between the people who want to drill and the people who don’t. But actually, this negotiation is between people and physics. And therefore it’s not really a negotiation.

Because physics doesn’t negotiate. Physics just does.

In a sense he right. How a system (our climate) responds to changes (increasing anthropogenic greenhouse gases in the atmosphere) is set by basic physics, and no amount of wishful thinking will change that. However, this is essentially always true. That something will happen doesn’t immediately tells us what we should do. That our climate’s response to anthropogenic influences is set by physics doesn’t immediately mean that we should, or should not, do something specific. In my opinion, we should be using physics to make an argument for why we should – or should not – do something, not simply say “physics says we mustn’t do this”.

To be clear, Bill McKibben’s underlying argument is reasonable; that responding to climate change may be inconvenient does not influence what will happen. Neither do our values or what is politically feasible. We can’t negotiate with physics; we simply need to decide how best to proceed, given our understanding of how the physical system will respond. My main issue with much of this debate is those who either suggest that it won’t respond how we think it will, or who select a possible – but unlikely – outcome to justify their preferred policy.

In my opinion, we really should be accepting our best scientific understanding when trying to motivate a particular policy option. Although I suspect that Bill McKibben does accept this, I think it’s a pity that he didn’t use this to motivate his argument, rather than simply essentially claiming that not being able to negotiate with Physics makes the option obvious. It might be to him, but maybe not to all.

Of course, I realise that I’m looking at this from the perspective of a scientist who would like people to at least gain some understanding of the physical system, and then use that understanding to inform their decision making. It’s quite possible that this is naive and unrealistic. Maybe – as a campaigner – Bill McKibben’s goal is simply to get a message out, and to try to make a strong and convincing argument. In fact, one reason I thought I’d post this is to get some views from others as to what we should expect from campaigners, compared to what we might expect from professional scientists. I don’t think we can hold them to the same standards. There’s a difference between using the scientific evidence to support a preferred policy option, and explaining our best scientific understanding.

Given that this post is about how Physics should motivate our policy decisions, maybe I’ll express mine. I think our basic understanding of physical climatology tells us that we should reduce emissions as fast as possible. Okay? But what do I mean by “as fast as possible” and and how do we actually do so? As I think I may have said before, this – in my opinion – is the most difficult aspect of this whole topic, and I don’t know the answers to either of those questions (well, apart from the fairly obvious step of introducing a carbon tax). Also, since I’m having a brief discussion with Richard Betts about this type of thing on Twitter, I’ll also make clear that this isn’t an argument about “mitigation” over “adaption”. Some level of adaptation is unavoidable and clearly our understanding of the physical system will inform both what mitigation strategies we should be pursuing, and what type of adaptation we should be adopting.

Posted in Climate change, ClimateBall, Science | Tagged , , , , , | 73 Comments

A powerful speech

Climate Crocks has already covered this, but I’ve been busy (lazy?) and so thought I would post this too. It’s a speech by US President, Barack Obama, in Alaska, at a meeting about Global Leadership in the Arctic. It’s a remarkably powerful speech and he seemed incredibly well informed. The first half is particularly good, and I could not find something that the usual suspects could justifiably criticise. To be clear, that’s not me suggesting that they won’t find something to criticise (because ignorant pedants always do), just that he seemed to say things carefully and was clearly well advised.

I’ll let you make up your own minds about the significance of this speech, but I certainly couldn’t imagine any other world leader today making a speech of this calibre. In fact, I didn’t even expect to hear the President of the USA doing so. In my opinion, it’s a welcome change.

Posted in Climate change, Global warming, Science | Tagged , , , , , , , | 105 Comments

Spreading misinformation, intentional or not

Rick Santorum appeared on Bill Maher and, when asked about climate change, claimed that there was a recent survey showing that 57% of scientists don’t agree that CO2 is the main control knob for our climate. The survey that he is referring to appears to be the one by Verheggen et al. (2014), which you can read about here. It should be patently obvious that their conclusion is not that a majority of scientists disagree that CO2 is the main climate control know. If anything, it’s the opposite of that; a majority of scientists agree that the dominant cause of our recent warming is anthropogenic.

Bill Maher responded to Rick Santorum with I don’t know what ass you’re pulling that out of. Unless I’m mistaken, I think this claim originates from Fabius Maximus who re-analysed Verheggen et als. survey to claim that only 43% of scientists agree that we are 95% sure that man-made CO2 is the dominant driver of climate change.

Well, I’ve discussed this before and you can read Bart Verheggen’s explanation for why this is wrong here. Essentially, Fabius is arguing that only 43% of those in the survey agreed that more than 50% of the warming is anthropogenic AND that this was extremely likely (> 95%). One problem is that the question that his claim was based on had a very high fraction of respondents (22%) who didn’t actually respond with what they thought the human GHG contribution was. Verheggen et al discuss this at length in their paper, and in the blogpost, and conclude that including them skews the result to – probably – a lower value than is reasonable. This conclusion is based on what respondents mentioned themselves, and on comparing results to another survey question about the causes of global warming. This is in addition to Verheggen et al. going out of their way to include contrarians, which also probably produces a slight under-estimate of the actual level of consensus.

More fundamentally, though, Fabius’ analysis illustrates a lack of understanding of attribution studies. An attribution study is really a null hypothesis test. In this case, the null hypothesis is that more than 50% of the warming could be non-anthropogenic. This is rejected at the 95% confidence level, resulting in the conclusion that it is extremely likely that more than 50% of the warming is anthropogenic. Asking individual scientists what confidence they have is not the same as a formal attribution study. Also, the consensus is simply that more than 50% of the warming is anthropogenic. The extremely likely is the confidence we have in this consensus position. What’s relevant is the level of agreement with this consensus position, not how confident individual scientists are in this position. Or, more correctly, arguing that only 43% of scientists personally think that it is extremely likely that more than 50% of the warming is anthropogenic, is not the same as only 43% agreeing with the consensus that more than 50% of the warming is anthropogenic. It is clear from the Verheggen et al. study that a large majority of those surveyed agree that more than 50% of the warming is anthropogenic.

If you’ve read much of Fabius’s blog, you might notice that he spends a reasonable amount of time commenting on how the public debate about climate science is broken. Well, yes, this may well be true. However, a good deal of this can be attributed to the mis-information being spread by those who would rather we didn’t take this issue seriously. That his re-analysis of Verheggen et als. study seems to have contributed to this seems remarkably ironic. This may not have been his intent, but that he has done so seems clear; well, unless Rick Santorum is referring to some other analysis that also produced a value of 43%. If so, I haven’t come across it.

Posted in Climate change, Climate sensitivity, ClimateBall, Global warming, IPCC, Science | Tagged , , , , , , , | 108 Comments

Calling out alarmism

It was quite interesting to observe some of the defenses of yesterday’s Sun article by a wannabee journalist. One was that it somehow compensated for alarmism in the media. Well, that you think someone else’s article is wrong, doesn’t make this one less wrong. Another was criticising climate scientists for attacking this article, but not calling out alarmism in other articles. This is a fairly typical argument; climate scientists can’t be trusted because they don’t call out alarmism, or they’re not being consistent because they criticise one “side”, but not the other.

Such claims are, firstly, not really true, but there is also something that people who make such claims should think about a little (assuming they’re interested in actually giving this any thought at all, that is). Whether we should be alarmed, or not, about the consequences of climate change is a judgement. It’s a complicated situation and there are many valid ways in which to consider this. As a scientist, my interest is in what evidence people present in support of their position, not in what judgement they’ve chosen to make given that evidence. Scientists may disagree with the judgement someone has made, but scientists don’t have some kind of right to only allow people to use the evidence to make judgements with which they’d agree. The important thing scientifically, in my view, is whether or not they’ve presented a reasonable representation of the available scientific evidence, not what judgement they’ve drawn, given that scientific evidence.

For example, consider an article that has a rather alarmist tone and that suggests that we could see substantial sea level rise in the next century, a substantial increase in global surface temperature, increases in the frequency and intensity of some extreme weather events, changes to the hydrological cycle, a significant increase in ocean acidification. I – and other scientists – may disagree with the tone of the article, but if the article has presented a reasonable representation of what is possible (with suitable caveats), what is there – scientifically – to criticise? Scientists aren’t here to tone troll the media. In some sense, they’re not even here to correct the media, but if they are to do so, their expertise might suggest that they should be critising the interpretation of the scientific evidence, not the judgement that the author has chosen to make, given that evidence.

So, maybe the reason climate scientists appear to criticise one “side” more than the other, is that one “side” (as illustrated by yesterday’s Sun article) typically publishes articles that are full of scientific errors, and the other does not. There might be some articles that are alarmist and scientifically wrong, and others that show little concern and represent a reasonable interpretation of the evidence, but I’d be surprised if you could find many examples of such articles. Of course, feel free to prove me wrong through the comments.

On that note, I thought I might advertise Doug McNeall’s second installment of his series on how to win at Twitter (which I suspect was partly motivated by yesterday’s Twitter storm over the rather silly Sun article).

Posted in Climate change, ClimateBall, Satire, Science | Tagged , , , , , , | 110 Comments

At least do a little bit of background research!

The Sun appears to have some kind of competition called The Great British Sound Off which aims to find a great Sun columnist. One of the finalists is a 19 year old called George Harrison who’s piece is called give climate hotheads the (ice) cold shoulder which seems to indicate that what the Sun is looking for is someone with the strength of their convictions, but little else. You’d like to think that the authors of such pieces would at least do a little bit of background research. It wouldn’t even take very long, which I will illustrate by writing this post in a matter of minutes.

George’s article kicks off with the witty (not really) comment

THE US climate change fanatic Al Bore once famously predicted sea ice would be all but gone by now.

A very quick google search would reveal that what Al Gore actually said was

One study estimated that it could be completely gone during summer in less than 22 years. Another new study, to be presented by U.S. Navy researchers later this week, warns it could happen in as little as 7 years.

Thats not a prediction that it would be all gone by now. It’s pointing out that some researchers have warned that summer Arctic sea ice could be gone by now, but not a prediction that it actually would be.

Next we have

But news just received from the European Space Agency has revealed an inconvenient truth for the climate alarmists.

The volume of polar sea ice actually increased by a third in 2013.

This is actually only about Arctic sea ice, and is from this paper, the abstract of which actually says

Despite a well-documented decline in summer Arctic sea ice extent by about 40% since the late 1970s….

Between autumn 2010 and 2012, there was a 14% reduction in Arctic sea ice volume, in keeping with the long-term decline in extent. However, we observe 33% and 25% more ice in autumn 2013 and 2014, respectively, relative to the 2010–2012 seasonal mean, which offset earlier losses.

The figure on the right should also put it into context. The sea ice volumes in September 2010, 2011, and 2012 were particularly low; well below the long-term trend. The increases in 2013 and 2014 might seem substantial relative to these low values, but the values are still within one standard deviation of the long-term trend. This is not indicative of some kind of recovery and is not some kind of inconvenent truth. Such variability is to be expected.

We then get

And now the scientific community is bickering while our supposedly endangered planet is still doing just fine — surprise, surprise.

Hmmm, the scientific community isn’t really bickering and what’s being suggested is that continuing to increase our emissions may lead to some very severe consequences in the future.

Followed by

Why do we place so much trust in the climate scientists and their Doomsday predictions? TV’s Mythbusters would do a better job of getting the global warming facts straight.

Maybe George should avoid getting his information from climate denial sites, and should realise that Mythbusters is a TV show.

Anyway, that’s been about 15 minutes and is pretty much all I can be bothered doing. It wasn’t hard, but maybe simply making stuff up is easier than actually doing some background research or talking to people. I’d recommend the latter if George is interested in presenting a reasonable representation of our actual scientific position. On the other hand, if he’s only interested in writing for the Sun, maybe he can simply carry on as he is.

Posted in Climate change, ClimateBall, Satire, Science | Tagged , , , , , | 57 Comments

BBC and the Met Office

It’s very disappointing that the Met Office has lost the contract to provide weather reporting for the BBC. It’s a world-class organisation and it’s hard to see another providing the same level of service. Maybe cheaper, but better seems unlikely.

This, however, gives me an opportunity to mention two thoughts (which you can take with as big, or as small, a pinch of salt as you’d like) about the Met Office. The Met Office is not only publicly funded, but is also formally part of the Public Sector. I can see two basic arguments for why it might be better if it were to be private, even if it were still essentially publicly funded.

One is that being part of the public sector means that Met Office staff have to be careful about expressing views with regards to policy. My understanding of this rule is that it is based on the idea that public sector workers are required to implement whatever policy the government of the day would like implemented, and should do so without prejudice. Seems perfectly reasonable to me. Scientists, however, are not implementing policy, but are – at best – informing policy. Ideally scientists should also have academic freedom. Restricting those who happen to be public sector workers seems to undermine this fundamental part of the scientific process.

Furthermore, I sometimes get the impression that this restriction filters out into the broader scientific community in the UK. This could be because many have an association with the Met Office, but sometimes appears related to the whole science/advocacy issue when – as far as I’m aware – it’s simply intended as a mechanism for maintaining public sector objectivity. It’s not that I think scientists should be advocating, but I do think scientists should be free to express whatever views they would like.

The other advantage I can see with the Met Office being outside of the public sector is that they might feel less obliged to pander to the likes of Keenan, Montford and their ilk; those with a ratio of confidence to actual competence that’s approaching infinity. Being more able to say “sorry, you’re talking bollocks and spreading mis-information” would be doing the public a great service. Of course, I’m not suggesting that they use those words exactly, but being able to be more direct would – in my opinion – be quite valuable.

To be clear, I’m not arguing that it would be good if the Met Office were privatised; simply expressing some views as to possible disadvantages of being in the public sector. There are many other reasons why it may well be much better to stay as it is. It’s clearly a very important organisation that provides a crucial public service, with a wide range of different roles. Maintaining this level of service is very important and risking it would – in my view – be a huge mistake. That’s why it’s hard to see the logic behind the BBC changing its weather reporting provider. The Met Office is not only a national service, but it appears to be one of the best in the world. Apart from saving some money, what advantage can there be to changing to a provider that neither has the Met Office’s history, nor it’s expertise? Seems rather short-sighted to me.

Posted in Climate change, ClimateBall, Science | Tagged , , , , , | 73 Comments