Saturday, July 18, 2015

GISTEMP only 0.04°C Behind Models

With GISTEMP's new datasets, I thought I'd update (from here) its comparison with CMIP5 models. (Again, GISS's updates are explained here.)

I'm comparing the total warming for each dataset, calculated as linear_slope*time_interval, as time goes by:


I choose the scenario RCP8.5 for comparison, but it doesn't matter much as all the RCPs use the same historical data up to 2005 and get essentially the same results 'til now. (They aren't exactly the same, I guess because the models are spun up to slightly different equilibrium states before beginning their calculation in 1880).

The model is 0.04°C (5%) ahead of observations.

A Current Comparison of Models and Observations

As you probably heard by now, GISTEMP measured June as the warmest June on record. Also, they have updated their methodology -- you can read more here. Basically, they updated their land and sea surface numbers to the new versions put out by NOAA in the recent Karl et al paper in Science. (Reminder to people who don't like new data -- the Karl et al changes are smaller than the recent UAH changes to their lower troposphere numbers.)

With that, here's the model-observation comparison Gavin Schmitt of NASA GISS tweeted the other day (though I'm not sure why he wouldn't use CMIP5):

Which comes with the usual caveat:

Thursday, July 16, 2015

“The smallest feline is a masterpiece.” - Leonardo da Vinci


Interesting Graphs from NOAA's Press Conference

A few graphs I found interesting from today's press briefing by NOAA on the State of the Climate 2014 -- because you can never have too many summary graphs that extend over several decades.

Reanalysis shows more warming in the lower troposphere in the last 15-20 years than does UAH or RSS (this graph is from UAH's v5.6 dataset, not the latest v6.0beta2, perhaps because the latter hasn't been published yet (as far as I know):


Changes in extreme days:


Rise in global mean sea level, with contributions from the increase in ocean mass (mostly from land-based glaciers melting) and from "steric" changes due to the thermal expansion of ocean water. It's about 2-1 for the mass increase, and their sum is the total change in sea level:



Changes in North Amerian snow cover:


Temperature changes at depth (60 feet) for several permafrost sites in Alaska:


NOAA's prognosis for coming years was (of course): more of the same.

Wednesday, July 08, 2015

Fwd: Breaking News: South Carolina House Backs Removal of Confederate Flag

Yippee. Shame it took a mass murder to accomplish this, but it seems people do still have hearts beating under their shirts & blouses.

That's what passes for hope these days.

-------- Forwarded Message --------
Subject: Breaking News: South Carolina House Backs Removal of Confederate Flag
Date: Thu, 09 Jul 2015 01:12:13 -0400
From: NYTimes.com News Alert <nytdirect@nytimes.com>
To: david.appell@gmail.com


Breaking News Alert - The New York Times

Add nytdirect@nytimes.com to your address book.
BREAKING NEWS
South Carolina House Backs Removal of Confederate Flag

Thursday, July 9, 2015 1:09 AM EDT


Voting to jettison a divisive symbol that has evoked slavery and segregation for some and history and Southern pride for others, the South Carolina House of Representatives early Thursday backed a proposal to remove the Confederate battle flag from the State House grounds. It was an action that would have been politically inconceivable just three weeks ago.
The bill still faces a final test in the 124-member chamber. But the 93-to-27 vote, more than the two-thirds needed for final passage, raised hopes among the proposal's supporters that the flag would be lowered by the weekend.
The State Senate approved the measure this week.
Before the vote, legislators spent much of Wednesday locked in an emotional debate about the proposal. Supporters of removing the flag fended off amendments that could have jeopardized the bill's prospects of final passage.
Read more »



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The Progression of the Western Drought

From the Pacific Northwest Climate Impacts Research Consortium (CIRC) newsletter:

The Internet: "A Sinkhole for the Gullible"

I thought this was especially tenchant, from Frank Bruni's recent column on anti-vaxxers, but pertaining to other debates too:


Sunday, July 05, 2015

And the Rest of You Are On Your Own

Friday, July 03, 2015

Why Very Warm Events are Exponentially More Probable in a Warmer World

As you've heard, it's been extremely hot in the US Northwest -- it's 98°F as I start writing this at 6 pm -- and very unpleasant. It feels like Arizona -- walking outside is like walking into a furnace. (Our normal high for the day is 79°F.) I never run my air conditioner until it's time to go to bed, so the cats can go in and out of the back door as they want, but today at 4 pm I just couldn't stand it anymore and turned it on.

In June, there was only one day here in Salem that was below normal -- June 1st, at -0.5°F below average. For the month we were 7.5°F above average, with only 0.67 inches of rain, just 45% of average. Ugly.

Is this high, prolonged heat wave due to manmade global warming? Would this heat wave have happened in a world without AGW? I don't know. Cliff Mass says it's just natural variability, but others have disagreed with him in the past.

But here's something: a warmer world increases the chances of extreme temperatures exponentially.

Here's what I mean, with some gory details, but not too bad. And I get to practice my LaTeX, which I wrote my thesis in but haven't used since.

Suppose the background temperature of the world is T1, and we want to calculate the probability of an event with temperature T -- that is, the change of occurence of temperature T.

A few years ago Tamino calculated the probability spread using data for the continental US (USA48), and got the figure to the right. It's very close to a normal (Gaussian) distribution, and that's what I'll assume for the spread of probabilities. We're calculating the vertical distance between the blue and red curves, for any value of temperature along the x-axis.

As Wikipedia says,


So, if the background temperature is T1, the probability of the occurrence of a temperature T is


Now suppose the world gets warmer, and the background temperature changes from T1 to T2, both less than T. Let ΔT = T2 - T1 be the amount of warming.

There is a similar equation to the above for p(T,T2), the probability of an event with temperature T in the warmer world T2, just by replacing T1 above with T2. I'll assume the spread of the distributions, σ, is the same in both worlds. 

We want to calculate the change in the probability, Δp, of the event with temperature T:


as a function of ΔT.

After some algebra, we find


where it's understood, just to make things look simplier, T, T1 and T2 are all divided by σ√2.

We can gnaw on this further to get


where I've used the fact that 


(except maybe on Venus!). All the crap on the left-hand side is junk, not dependent on ΔT. So we get


where f is some function we don't really care about here.  

So -- for a temperature change ΔT, the probability of the occurrence of temperature T goes up exponentially. 

This, it seems to me, is proof of why extreme temperatures get much more likely in a warming world, faster than the linear amount by which the world warms. 

Tuesday, June 30, 2015

GISTEMP Estimate for June: A Record High

My estimate for June's GISTEMP, using the daily University of Maine Climate Reanalyzer data, is 0.83°C. 

That would be a record for the month, above June 1998's 0.75°C. The 1998 El Nino isn't looking so remarkable anymore.

This estimate, if accurate, would also be the 6th-warmest of any month in GISS's records, which start in 1880.

We'll see. I wasn't very close last month -- too high by 0.12°C. Here's my record so far; my overall average is very close, but for individual months not as much:



Monday, June 29, 2015

EconTalk Podcast has Matt Ridley This Week


EconTalk

EconTalk



Posted: 29 Jun 2015 04:30 AM PDT
Science writer and author Matt Ridley discusses climate change with EconTalk host Russ Roberts. Based on his reading of the scientific evidence, Ridley describes himself as a "lukewarmer." While Ridley agrees that humans have made the climate warmer, he argues that the impact is small or positive over some temperature ranges and regions. He rejects the catastrophic scenarios that some say are sufficiently likely to justify dramatic policy responses, and he reflects on the challenges of staking out an unpopular position on a contentious policy issue.
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0:33 Intro. [Recording date: June 18, 2015.] Russ: We are going to talk about climate change, your view of the state of our scientific knowledge and some controversies you've been in. How has your thinking on this evolved over time? Give us some background. Guest: Well, I've covered climate change as a journalist for more than 25 years. I first wrote about it in the late 1980s, for The Economist. At the time I took everything that alarmed scientists were saying at face value. I gradually became more skeptical, in the 1990s. I then returned to alarmism, for a while, because of seeing the hockey-stick graph, which seemed to me to demonstrate unambiguously that what was happening today was much more drastic, was unprecedented and much more drastic, than what we'd seen. So, when I discovered that that graph was actually very misleading, once you understood the statistics behind it, I began to look at all the rest of the evidence. And the more I looked, the more skeptical I got. Not about the idea that climate change is--not about the idea that mankind can influence the climate. Not about the idea that carbon dioxide, greenhouse gas, but about the idea that we are totally likely to see dangerous climate change within the next hundred years or so. Russ: So, we are going to come back maybe and talk about the hockey stick. But one issue that hangs over this conversation and that hangs over our conversations here at EconTalk on economics many times is this issue of 'the facts.' And I find it remarkable, the deeper you dig into something, the more often you realize that the facts are a little bit ambiguous. Uncertain. They are created. They are not just coming down from Sinai. And when people tell me, 'Well, the facts speak for themselves,' I always get suspicious. Because they never do. They have to be prepared and measured and packaged, and that often makes a difference. Now, as you said, you are not skeptical about a lot of things; in fact you describe yourself as--and I love this phrase--a 'lukewarmer.' That's one word. That's not a name. That's not Luke Spacewarmer--although that would be an interesting character, I think, if we had a graphic novel about a project. But, what do you mean by a 'lukewarmer'? Guest: What I mean by a lukewarmer is somebody who is not challenging the idea that carbon dioxide levels are increasing or that carbon dioxide is a greenhouse gas or that we have seen warming in recent years or are likely to see warming to continue. But is challenging the idea that there is a strong likelihood that this will turn dangerous at some point in the future. In fact, I would often go further and say, actually, there's pretty good evidence that the carbon dioxide emissions we are putting into the atmosphere as fossil fuels are in many ways improving the environment. By that I mean we've seen a 14% increase in the amount of green vegetation in the planet in the last 30 years. Almost certainly largely because of the extra CO2, which is enabling plants in all ecosystems to grow more vigorously. And that has slightly improved the greenery of the planet, particularly in arid areas like the Sahel and Western Australia. So there are really quite--and I haven't even begun to mention the effect of slightly more rainfall on crops, and so on. Drought on the whole has been decreasing over the last 30 years. So, there are all sorts of reasons for thinking that for the planet as well as for mankind, carbon dioxide emissions are a good thing. A far bigger example of course is that if we burn coal oil and gas, we don't burn wood. And so we don't chop down forests. There is no doubt that switching to fossil fuels enabled us to stop destroying forests on a massive scale. Particularly in the Western World, where forests are recovering a lot of land very rapidly. So, I think the conversation about climate change is often terribly one-sided: Talks only about the damaging impacts and never about the positive impacts of fossil fuels and their emissions. And a 'lukewarmer,' like me, is someone who thinks that we are unlikely to see dangerous climate change; we are quite likely to see benefits. Meanwhile, this doesn't make me someone who is not concerned about the environment. I think there are some very serious environment challenges. Top on my list is invasive species, which are helping to decimate native species on particular islands all over the world, still. This has been a big problem for hundreds of years; it's getting worse at the moment. And I think those issues have been neglected. Because we are spending all our time talking about climate change.
5:25 Russ: So, when you suggest that it might actually be good for humanity or the world to have more CO2, that must drive some people very crazy. And we will talk about the kind of reactions you've been getting over the last few years to your writing and positions. But, why do you think--to focus on the key part, I think of the lukewarming, the lukewarmer position--that there's little or no risk of dangerous climate change? So there might be--we've had, I think 8/10ths of a degree Centigrade of warming over the last, I forget, how long. The worry is we might go to 4. Or 6. Why aren't you worried about that? True, it might be, the dose makes the poison. Maybe a little bit more CO2 is better for the environment--for human life and the planet. But we get into the range of the higher increases that some people are worried about, those would seem to be pretty dangerous. Guest: Yes. Well, two reasons. One is because the rate of warming has been much slower than predicted. So, if you go back and look at what the IPCC's (Intergovernmental Panel on Climate Change) climate models have predicted, we have seen much less warming over the last 20 years, 30 years, 40 years, 50 years, than those models have predicted. We've seen a little more than 0.1 degree per decade. The IPCC, remember in 2013, came out and said that it is very confident that more than half of the warming since 1950 is man-made. Now, we've have 0.8 of a degree since 1880. About 0.5 of a degree since 1950. More than half of that is 0.25 of a degree. So they are saying that something like a third of a degree of warming is man-made over 50 years. Now that's extremely hard to measure. And we've got no really good evidence that we are measuring it accurately. In fact, the surface temperatures tend to find a slightly faster rate than the satellites. Which implies that we are contaminating the record with urban heat island effects and things like that. Local warming, in other words, not global warming. So that's the first reason--is that we've got nothing in the data that we've seen so far to suggest that increasing carbon dioxide from 0.03 to 0.04%, which is what we've done, has produced anything like the speed of warming that we would expect if the models were right. The second reason is that the models are assuming something which we now know pretty well not to be true. And that is that the carbon dioxide warming will be hugely amplified by a water vapor warming. It's a very little-known fact, which is often kind of kept of the conversation, to my frustration, that it's widely agreed by the IPCC and everybody else, that if you double carbon dioxide, you only get 1 degree of warming: 1.2, 1.1, that sort of zone of warming. Russ: If you double the stock-- Guest: If you double the levels of carbon dioxide in the atmosphere. Don't double emissions, but double the level in the atmosphere. From 300 parts per million to 600 parts per million, or 400 to 800. It doesn't matter where you double from because the graph is curved. You double from 800 to 1600, you still expect to get 1 degree of warming. That's the way the arithmetic works. So, why do they say that their estimate of climate sensitivity, which is the amount of warming from a doubling, is 3 degrees? Not 1 degree? And the answer is because the models have an amplifying factor in there. They are saying that that small amount of warming will trigger a further warming, through the effect mainly of water vapor and clouds. In other words, if you warm up the earth by 1 degree, you will get more water vapor in the atmosphere, and that water vapor is itself a greenhouse gas and will cause you to treble the amount of warming you are getting. Now, that's the bit that lukewarmers like me challenge. Because we say, 'Look, the evidence would not seem the same, the increases in water vapor in the right parts of the atmosphere--you have to know which parts of the atmosphere you are looking at--to justify that. And nor are you seeing the changes in cloud cover that justify these positive-feedback assumptions. Some clouds amplify warming; some clouds do the opposite--they would actually dampen warming. And most of the evidence would seem to suggest, to date, that clouds are actually having a dampening effect on warming. So, you know, we are getting a little bit of warming as a result of carbon dioxide. The clouds are making sure that warming isn't very fast. And they're certainly not exaggerating or amplifying it. So there's very, very weak science to support that assumption of a trebling. Now the really interesting thing is that when the Intergovernmental Panel on Climate Change came out with this latest report on this--the main report was in 2013, the follow-up report was last year in 2014--they had before them 14 different peer-reviewed papers of this climate sensitivity issue, all of which pointed to a much lower climate sensitivity than they had been assuming in the past. And these are the ones based on observational data. And rather than adjust their--so, what they did, they adjusted the range of climate sensitivity they think is likely, downwards slightly, from the previous year, from the previous report in 2007. But they did not give a best estimate of climate sensitivity, which had been 3 degrees in 2007. They simply didn't give one. They simply said, 'We don't know what the best estimate is.' Now, that's been completely ignored in all the impact models that countries are using around the world to estimate how much warming they are going to get and what the effect will be on people's livelihoods and sea level and so on. They've gone on assuming that the best estimate is 3 degrees. Whereas, pretty well every scientist who is working on this is now accepting that climate sensitivity is in the 1-2 degree range. So--and that, by the way, explains, in an instant, the rate of warming we've had over the last 50 years. If it's only in the 1-2 degree range, climate sensitivity, then that would explain why we've only had a third to a half degree of warming in 50 years, when we should have had much more than that. So, if you see what I mean, both the theory and the data support lukewarming and not alarming warming. Why is everyone going on about the future being alarming? Because there's a huge vested interest in that now.
12:45 Russ: So, we had Martin Weitzman on recently, who, with Gernot Wagner is the author of Climate Shock. And he takes--Weitzman takes what he calls a precautionary approach, a fat-tailed approach. He says, 'True, it's not so likely that we are going to have catastrophic warming, but since there is a chance, a prudent approach is to take precautions and to reduce the possibility of that catastrophic outcome.' In fact, his--the level that he's worried about is the 700 parts per million--I think we're around 400 right now? Do I have that right? Guest: Yes. Russ: High 300? Guest: Yes. 0.04% or 0.07% is I think a more accurate way of describing it, but it doesn't sound so big. So they [?]. Russ: Right. So, it's parts per million. So, it's a small number. But that's life. So, his worry is that in the next hundred years, which is a long time but it's a short time when lifespans are expanding and we have direct worries about our children and grandchildren--over the next hundred years we could hit 700. Seven hundred could--I think he suggests there's a 10% chance that could lead to 6 degrees of warming. You are suggesting that's just not possible, given the relationship between carbon dioxide concentration and temperatures that we've observed in the past. Now, the question would be--so, one, I want you to verify that they've got that right. And then, two, the question would be: It is possible that there are other things going on; that the reason we've only seen this small of warming we've had so far is because of sun spot activity, volcanic activity, ocean changes--who knows? What do we know about any of that? Guest: Yeah. Well, you are quite right. There are huge uncertainties. We don't know about all of that. And one of the frustrations has been these recent papers saying things like 'All the warming has gone into the ocean,' and then instead of that being a guess, hypothesis, a preliminary discovery, it becomes, 'Oh, they've solved the problem.' And therefore, you know, etc. Premature consensus, premature certainty being declared the whole time in this debate. Which is very dangerous. But back to the main point about Martin Weitzman's fat tails: You describe his point very accurately. And it is a well-known argument that a small possibility of a very large disaster needs to be taken seriously. It's in a sense the same idea of the Black Swan argument, that Nassim Taleb puts forth-- Russ: And he says the same-- Guest: and I would argue that it actually--sorry. Russ: Taleb has made the same point about climate change. Guest: He has indeed. Russ: He's in the same camp. Guest: And I would argue that it's a new version of Pascal's Wager--if you remember, Blaise Pascal said, 'I don't think God exists, but if he does, I'm in much deeper trouble for not believing in him. Whereas if he doesn't it doesn't matter. Therefore, it pays to believe in him--[?]' Russ: Rather than take a chance. Guest: [?] Rather than take a chance. Russ: Eternal damnation is a big negative, so a few years of religious observance is a good investment. That's the argument. Guest: Correct. Exactly. And I think that's a slightly closer analogy than other people would think. In other words, I think there's an element of sort of religiousness in all of this. But, why do I think that Weitzman's approach in that respect is not the right way to think about it? Two reasons. One is empirical: that actually the fat tail on the distribution, the relatively significant even if small possibility of a really big warming has got a heck of a lot thinner in recent years. This is partly because there was a howling mistake in the 2007 IPCC Report, the AR4 Report (Fourth Assessment Report: Climate Change, 2007), where a graph was actually distorted. And a brilliant scientist named Nick Lewis pointed this out later. It's one of the great, shocking scandals of this, that a graph--and I'm literally talking about the shape of the tail of the graph--was distorted to make a fatter tail than is necessary. When you correct that, the number gets smaller. When you feed in all these 14 papers that I've been talking about, all the latest observational data, 42 scientists involved in publishing this stuff, most of the mainstream scientists--I'm not talking about skeptics here--when you feed all that in and you get the average probability density functions for climate sensitivity, they turn out to have much thinner tails than was portrayed in the 2007. And that Martin Weitzman is basing his argument on. So the 10% chance of 6 degrees of warming in 100 years becomes much less than 1% if you look at these charts now. So, we've got to update our knowledge based on our latest information. And after all, we've got 5 more years of data, and 5 more years of relatively slow warming, and 5 more years of knowledge about watching the past. And by the way, one of the excuses for lack of warming for the last 50 years has since been exploded. And that is the aerosol one. It used to be thought that we were dampening warming by putting so much sulfate into the air through the burning of coal. There is an effect there; but it turns out that now we know more about it, that effect is smaller than we thought. So, for all these reasons, the tail is very thin. The probability of really dramatic warming is extremely small indeed, now. It's been narrowed down. And that is acknowledged in the last IPCC report--not explicitly enough for my liking, but it is there. And it's got to the point where it's so thin that, in my view, it deserves no more attention than the small possibility that we will be hit by an asteroid. The small possibility there will be a catastrophic volcanic explosion. The small possibility that the measures we're taking against climate change, including renewable energy and preventing people getting hold of fossil fuels and things like that, will itself be very dangerous. All these things could be dangerous. I mean, aliens could arrive, even take over the planet. Should we spend a lot of money now to try and prevent that possibility? You have to, at some point, take a reasonable view that certain possibilities are too small to spend a fortune on. Russ: Well, some would argue that if aliens attack the planet, it would stimulate the economy as we prepare for it. But I will leave that to another episode.
19:38 Russ: I want to mention two more factual issues, and then I want to turn to the social issue of how the climate science issue is getting discussed and the polarization of it, being written about recently. The first factual issue I want to mention is, when I sometimes suggest that I'm somewhat skeptical of our understanding of the relationship between human activity and the climate, I often am greeted with the clever response: 'Well, 97% of scientists disagree with you. And you are only an economist. So how can you hold that view given that there's this massive consensus that 97% of scientists are convinced?' What's your reaction to that? Guest: Well, I'm in the 97%. That is to say if it's true that 97% of scientists are all of a particular view about climate, then let's go and ask what that view is. And if you go and look at the origin of that figure, it was that a certain poll--of 79 scientists, by the way, an extraordinarily small sample--said that, 97% of them agreed that human beings had influenced climate and that carbon dioxide was greenhouse gas. Well, I'm in that group. Pretty well every skeptic I know is in that group. I'm amazed they found 3% that disagree with that. If you see what I mean. So, actually, whenever you hear that 97% number, it's not referring to a consensus about dangerous climate change. It's referring to a consensus about humans' ability to affect the climate. And that covers everything, from a tiny effect to a big effect. In other words, a subsequent paper which claimed that 97% of papers published in this area supported climate change--but again, it was just about supporting man-made climate change. It wasn't about supporting dangerous climate change. So when President Obama tweeted that 97% of climate scientists agree with climate change is man-made and dangerous, the first word was right; the second word was wrong. It's just not true. And I'm afraid he was just telling a lie or misinformed about that. There has never been any study which has shown that 97% of scientists think man-made climate change is dangerous. By the way--there was a much bigger survey of members of the American Meteorological Association, most of whom are scientists and all of whom are climatologists in some sense; and that--the figure there, when asked about 'How many of you think that climate change is likely to be dangerous?' the figure there was 52%. That was a huge difference-- Russ: Well, they still win. I'm joking. I'm laughing. Because I really resent--and this happens in economics as well, I really resent the implication that science is a majority rule process. It's vulgar. Guest: Yeah. And of course, you know, the whole point of science is that, as Richard Feynman famously said, 'Science is in the business of proving that experts are wrong.' And you know, until very recently, 97% of medics agreed that cholesterol was the cause of heart disease. Now, that's gone. That theory is wrong. Pretty well everybody--well, not pretty well everybody, but gradually, most people are realizing that that just ain't true. Dietary cholesterol, I should say. Cholesterol is involved in heart disease. But it's not because you are eating it in your diet. And that was based on very dodgy science in the 1950s. Which was enforced by a pretty ruthless consensus-building exercise that was pretty brutal to people who disagreed with it. And we see this again and again in science.
24:08 Russ: Yeah. It's in economics, as I said, as well. I find it very frustrating. It's obviously the case that at any point in time there can be disagreement about, say, cholesterol, about the causes of ulcers. It takes a while. It's not like everybody immediately sees the data and it immediately changes there mind. But eventually controversial theories get either accepted or rejected. And new things come along to change that. In economics--and I'm afraid in climate change, what they have in common is that they are multi-causal, complex phenomena using time series data frequently. It's very hard to measure these things with precision. And the other thing that I think I want to emphasize here, and I want to turn to, is this question of where the data come from. Talk about the hockey stick, the reaction to the hockey stick and the reaction to the reaction and what its impact on you was. Guest: Yes. The hockey stick is a chart of temperatures over basically the last thousand years. Produced in the late 1990s and based on so-called proxies. Now that means--you obviously can't go back and measure the temperature in, you know, Arizona or in 1420 because no one was walking around with a thermometer there. But what you can do is look at the width of tree rings. And if you make the assumption that trees are growing faster in warmer temperatures, then you can say it was warmer then or it was colder then, and you can produce a chart. And if you combine lots of these proxies, you come up with a rough estimate of temperature over the last 1000 years. And what it appeared to show was a sort of gentle cooling for most of that time, followed by a very rapid warming in the last 50 or 100 years. Russ: Corresponding to the onset of modernity, modern economic growth and human activity. Guest: Exactly. Exactly. Now it turned out that there were two things badly wrong with it. One was that many of the data sets, the most dominant data set of all, was from bristlecone pine trees in the American West, which had been explicitly gathered by scientists who knew they were measuring a different phenomenon, namely the fact that overgrazing in that area had caused tree bark wounds, which resulted in rather rapid growth as the tree tried to cover up the wounds if you like--of course stripped bark. But any way, the point was nobody who was actually measuring the tree rings of bristlecone pine trees thought that bristlecone pine tree ring width reflected temperature. So that data shouldn't have been used. And I'm simplifying a bit here--there's a lot of other details and a lot of other data to discuss. But the second problem, if you like, was that the statistical filter through which the data was passed, called short-centering, resulted in any data series which showed a 20th century optic being vastly exaggerated. Being able to influence the final outcome more than a hundred times. In other words, the statistical method was--and this was beautifully demonstrated by Ross McKitrick and Steve Macintyre, Canadian economist and mathematician, basically, who were incredibly diligent in tracking this down. And they showed that actually this method was fishing out any data with a hockey stick shape and giving it undue emphasis. So, what happens if you leave the bristlecone pines out, and one other paper from the Gaspé Peninsula in Canada? And the answer is if you do that the hockey stick disappears altogether. Now, this was known to the scientists doing the work, because they'd actually done that; and they accidentally revealed this when they sent a data file called 'Censored' into the public domain, which showed that they had discovered that without those two data sets they couldn't get a hockey stick. Now, you don't have to get lost in the details of this or start accusing people of malfeasance, which I'm not doing here. I'm just saying that this one incredibly influential graph--and it was influential, not only on me but on the world: it was used 6 times in the Second Assessment Report of the IPCC; it was displayed at the Press Conference when the Report was announced. It was a fantastically important chart. This chart was based on data which--you only had to take one data set out and the chart changes completely. Now, for me, that's a real alarm bell. That tells you that--you are potentially contaminating your conclusions with very, very suspect data. There were further attempts to sort of rescue the hockey stick which involved large trees from Siberia. And again, when you drilled down, it turned out that there was one incredibly influential larch tree in the sample. One tree. Russ: A single tree. Well, it could be very informative. But of course it could be that distinctive things happened in that neighborhood that had nothing to do with the world as a whole. That's the problem. Guest: Exactly. If you've got a larch tree growing in the shade and all the other larch trees fall down because of a storm and it's left alone in the sun, it will suddenly grow faster. That might have been what happened in the 20th century to that particular larch tree.
29:49 Russ: So this comes back to a point that Ed Leamer makes in his theme of taking the 'con' out of econometrics: which is, sensitivity analysis. That, when you present something, although it's more dramatic, can get you more attention when you just present one end of it, it's a good idea to describe how sensitive your results are to assumptions you make, to other variables, what their size might be, etc. But what I found interesting about--and I don't know anything about the larch trees of Siberia so I can't comment other than to agree that one tree seems unreliable--what we might call a thin reed to lean on--is the reaction when that was pointed out. And I think this whole--I would call it the sociology of science, the way this conversation moves forward is what's so depressing to me. And I think obviously to you, as you've written about it. And I want to turn to that. So, talk about how people reacted to that discovery and some of the other reactions that you've received when you've come out and suggested that maybe it's not as bad as it seems. Guest: Yes. Well, the person who has probably written most eloquently about this is Professor Judith Curry, who is a proper climate scientist unlike me. Russ: Previous EconTalk guest. Guest: Right, okay, yes. And she talks about--she's fascinating about the reaction of our colleagues, when she started having doubts about some of the--having been herself signed up to the mainstream view of this. And she started having doubts and challenging it and doing what she thought a scientist should do. And what we were all trained--those of us who did Ph.Ds. in science--I was in zoology; but you got gold stars in the class by saying during the seminar to the distinguished professor who was presenting his research in front of you, 'But have you thought about testing it this way?' 'Are you sure that this fact isn't caused by something else?' 'Maybe you are muddling cause and effect here.' Things like that. Etc., etc. You know, you were actually supposed to challenge. When she started doing that, and other people started doing that, instead of being allowed to have a conversation, it became, 'You've joined the dark side; you're a heretic; you're funded by fossil fuels. You're a denier'--which is an extraordinary phrase that began to be used for anybody who didn't sign up to alarmism and was deliberately intended to echo the Holocaust denial nonsense. And so, it became very much the psychology of taboo, in a phrase that's got often used. That it was taboo to question this. That if you thought that the hockey stick wasn't a reliable piece of data, then you were somehow sinning against the orthodoxy. And you were being unhelpful, because the world needed urgent action on climate change. And this continues to become more and more powerful of me[?]. And what you find now, for example in my profession, in journalism, very few people now ask the sort of question, the sort of skeptical questions about climate science that they do about economic policy, political policy, foreign policy, etc. They don't subject it to the same sort of scrutiny. Because they've been kind of frightened off by this, 'how dare you not join in this bandwagon.' Russ: It's a fascinating thing. Because--and it goes against the culture of the profession, as you point out. And yet in this corner I think it has an effect. Guest: Well, I've actually changed my mind a little on this. I used to think this was an exception, that science is actually, you know, the whole point of science is challenge, and so on; and I can see why in climate science this has happened. And that's because the IPCC process has kind of made a single church out of it, whereas science is often a very geographically enterprise with people in different universities all over the country and all over the world challenging each other. Which is actually quite helpful. The fact that there are rival groups prepared to say Professor Jones has got this wrong is what has kept science honest all these years. But actually if you look back at other episodes in science, there is a surprisingly strong tendency for this to happen. I refer again to cholesterol; I refer to Lysenko-ism--well, that was in a totalitarian regime where one biologist, Trofim Lysenko, was able to insist on his version of genetics and even got some of his opponents imprisoned. But you know, even things like continental drift and the age of the earth--it's often been very hard. Or you mentioned stomach ulcers. The two Australians who, 20 years ago, said 'I don't think stomach ulcers are caused by what we think they are. We think they are caused by a bacterium which is easily cured by antibiotics'--they were hounded and ridiculed and vilified for this absurd heresy, until they--well, they ended up with a Nobel Prize and we now realize that they were 100% right and the others were wrong. But it's not at all unusual for science to do this, to start championing one cause and making one church out of things. And by the way--there's an element of confirmation bias, and confirmation bias is an important aspect of what happens. In other words, if I champion, if I come up with a theory, then I'm not going to go out and look for ways in which this theory is wrong. I'm going to go out and look for ways in which this theory is right. Russ: Yeah, it's huge. Guest: And we all act like the prosecuting attorney who is trying to prove his case, rather than being--and sometimes will often claim we're the only person that challenges our own ideas. It's not really true, actually. Most of them actually look for confirmatory evidence. And by the way: I don't think we should stop them. I don't think it's possible to expect, you know, Professor Jones at such-and-such university has come up with a new idea to suddenly be his own worst enemy. It's just unrealistic, that. But what I do think we should expect is that Professor Smith should be Professor Jones's worst enemy. That's what's kept science honest over the years. Russ: That's right. And I've been writing recently about how hard it is for economists to change each others' minds with data; and that suggests that maybe economics is not so scientific. But the fact is, is that-- Guest: No, I think it's a very similar situation. I think you are absolutely right. Russ: Well, I'm thinking about Semmelweis and puerperal fever, when women were dying in childbirth. Guest: Absolutely. Russ: Semmelweis went out and he did a number of quick small experiments that confirmed his theory, which was people needed to wash their hands when they left the morgue when they left to deliver children, babies, in the maternity ward. And he was laughed at. And it wasn't open and shut, to the other people; in fact what was the opposite--his theories were obviously cranky[?] and crazy. Guest: Worse than laughed at. He was driven out. Russ: Correct. Guest: He went mad in the end, and all that.
37:47 Russ: So, speaking of going mad: You've been harassed quite a bit lately on a personal--by the way, the other part about this that's frustrating is you don't expect academics and scientists or social scientists in the case of economics to be name-callers. And I don't know whether this is an--accepting[?excepting?] to say this is a modern phenomenon. I suspect it's not. I have a feeling that scientists in the 18th century and 19th century were probably--had ad hominem attacks on their opponents as well. Guest: Yes, I think that's true, actually. Russ: It's a strange thing, though, that when you put an idea forward that you are called a bad name rather than having a patient explanation of why you are wrong. My view is that the angrier and ruder my opponents get, that suggests that I'm doing okay. Because if it weren't getting under their skin, that you'd just say, that's wrong and here's why, and it would be black and white, open and shut. And it's not. And that's part of the problem. But you've been under some attacks lately. So, what has happened, and what's that been like? Guest: Uh, yes. Well, just to illustrate your point, there's an old saying that when you are taking flak, you know you are over the target zone. Russ: There you go. Guest: But, I took a lot of personal attacks. People attacked my motives. And it's true that I have got personal investments in coal mining near my home; in fact, my family has been in it one way or another for a couple of hundred years. So, maybe I have a vested interest in carbon dioxide emissions. But I've always declared that; I've always made that very explicit. Russ: You owned that coal when you were worried about global warming. Guest: Well, exactly. That's right. Russ: Kind of gives you a [?]. Guest: [?] It's held me back. I've thought--I better not, I must be being influenced by my own vested interests here, so I'd better be careful. So, for a long time I hesitated before expressing my skepticism, for that reason. But, anyway: I was attacked for that. But extraordinary attacks. I mean, really bizarre attacks would come at me. Very personal, very rude. Often of the nature of this strange sort of fact-checking which doesn't check facts. Which says, 'His article is full of errors' and then doesn't actually give any example of anything that's an error. They might say, 'He said x but he didn't say y.' Well, that's not an error. It's an omission, but it's not an error. Or something like that. So, often--it got nastier and nastier. The more I put my head over the parapet of this. And eventually I wrote an article for the Times in London saying, 'Why is it? My views on this are pretty mild, actually. I'm a lukewarmer. I'm not a skeptic. Why are the attacks so nasty? Why do some of my colleagues in the House of Lords resort to impugning the quality of my Ph.D. thesis, which was on the behavior of birds 35 years ago.' Russ: I found that very entertaining. You wrote about that; I followed up and looked into it. It's amazing. Guest: But having--by the way, I'm sure the were mistakes in my thesis. But the very man who impugned me had been my thesis examiner and said it's a very good thesis. Russ: Yeah; that's awkward. It's very awkward. Guest: Anyway, I really wrote this up as a sort of entertaining story: This is what happens if you step into this arena. You get a lot of mud thrown at you. And I was really trying to be quite light-hearted and say this happens and it's where the world is. I wasn't trying to play the victim card or anything like that. Anyway, the reaction to this article was another of these pieces, in The Guardian dissecting [?] what an evil person I was to have written even this article. And the illustration at the head of this article was the severed head of a zombie. And the implication was that I was a sort of zombie person, whose views were so old-fashioned and so dead that they needed to be cut out. And the article virtually said as much. And then below the article somebody wrote a comment saying 'Shouldn't that be Matt Ridley's head in the picture?' And somebody else said, 'Isn't that going a bit far?' And he said, 'No, I think we should do this kind of thing.' This was the day that the Japanese hostage was beheaded in Syria. And then somebody else put a comment saying, 'The man who just made these two comments about Matt Ridley being beheaded is actually, although he is using a pseudonym, Jack Golgariev[?], and so occasionally he writes for The Guardian. He shouldn't be doing this. He's not just an ordinary Internet troll. That comment, was then removed by the editors. But not the comments recommending that I be beheaded. At which point, someone drew this to my attention, and I wrote a letter to the Editor of The Guardian saying that: 'Excuse me, this is technically hate speech and death threats, and I'm not going to give it to the police but I really do think you ought to do something about that.' And at that point they did intervene and remove these threats. But it took me three weeks to apologize for this. Now, I'm not, again, I'm not claiming that my safety was genuinely threatened here. But I am claiming that that goes too far. That, like, come on. All I'm saying is we think we may be spending too much money enriching wind farm tycoons and too little money reducing poverty with fossil fuels at the moment, because I don't think climate change is going to be as dangerous in 100 years' time as you think. I might be wrong in that. I might feel guilty in having that view in 50 years' time, as the weather heats up rapidly. But I don't think it's illegitimate for me to make that argument. And I certainly don't think it requires threats to cut my head off.
45:33 Russ: I'm on the same page there. I want to say, though--I want to digress here for a moment, and I want to mention that I get suggestions from time to time to have on this program people running for President, or current politicians. And I--I always respond by saying I don't believe in having politicians on EconTalk. Because they are not truth seekers. They are generally not educators. They are not interested in finding the truth. They have a message to deliver. And that's what they do. And nothing wrong with that. But that's not what we do here. So I do want to--I should say, Matt, that you are an exception to this policy. In some dimension you are an office holder. You are not an American, a member of the American political system. But you are in the House of Lords. And I have to also add that the dialog that you link to in a recent article, and we'll put a link up to it as well, where you are arguing with some fellow Members of Parliament, is just unbelievable. First of all, the quality is very high. Which is a tribute to the British educational system, where the British people--I don't know what it is--the idea that American members of Congress could argue with such eloquence on either side would be absurd. But you are a politician, in some dimension. So I just want to get that--we have to be honest about that. Guest: Yeah, indeed. Let me just pick you up on one word there: 'office holder' is wrong. I'm a back bench Conservative Member of the House of Lords. Which means I'm one of 800 people who are in a position where they can take part in debates and vote on legislation in the Upper House of Parliament. Which is, by the way, the far less powerful house--the house that always gives way on legislation. It's not as powerful as Senators or the House of Representatives in our system. So, in that sense, I am a very, very low form of life politically. But you are absolutely right: You know, I am a politician in that sense. But I am not a politician in the sense of being on message or representing a view of the government. In fact, judging by the exchange I had yesterday with a government Minister in the House of Lords, I am probably not the flavor of month with my own government at the moment. But that's another matter. And so, yes, you are right. I've found myself with this opportunity to express my views both in the political arena and through my journalism. But, debates in the House of Lords are often just about expressing views rather than insisting on policies, if you see what I mean. Not trying to influence policy-- Russ: But the other thing I want to clarify: Your position in the House of Lords. Are you up for election, in any time soon? Guest: Yes, well that's a very good point. I'm not running for re-election, ever again, because in theory I'm appointed for life now. Russ: How does that work? Guest: Well, everybody in the House of Lords is elected for life. They literally can stay there till they fall apart. People increasingly retire rather than fall apart. But there we go. I'm not--at most, nearly all of the House of Lords are appointed by either the governing party or by a different mechanism. I'm actually in an unusual group of people who hold hereditary titles like the ones that the barons of Magna Carta had. And a small percentage of whom are still allowed to sit in House of Lords, and they select among themselves who that group is. So, if you like, there's an Electoral College of hereditary peers who elect a small number to be in the House of Lords. I'm one of those. And the reasons I'm a hereditary peer is because three and a half generations, four generations ago, one of my ancestors was a senior Member of Parliament, an elected Member of Parliament, and was given a peerage by Queen Victoria in 1900. So I'm nothing like an ancient baron from Magna Carta time, but I have got one of these titles which enables me to stand for a sort of election, but a very small election, to the House of Lords. I'm sorry about that digression into--bizarre Constitution. Russ: Given that we recently--well, go ahead. Guest: My position may not last. I'm a group that is often thought to be an anomaly in the current Constitution. Russ: Kind of a dinosaur, right? Kind of perfect for our climate. For a lukewarmer. I think you are really holding an appropriate position in the government. We recently had an episode on the Magna Carta, here at EconTalk. And I want to say there is no limit to what you can learn by listening to this program. And that we've just had another example of that. For those of you who weren't quite clear on the House of Lords, we have I hope, made you wiser. So, that's good. Guest: I've only scratched the surface of the complications. Russ: Oh, I know. Guest: The way to think of the House of Lords is a gigantic think tank where we talk about things. I think. Russ: Well, as I said, the quality is very high.
49:14 Russ: Now, I'm going to put you in an uncomfortable position. You resent--as do I--when your opponents presume that you are not a nice person, that you must be the pawn of special interests. And yet, we also should judge our intellectual opponents the way we'd like to be judged. So, given how you are in a minority viewpoint, can you give us an interpretation of the people on the other side that is more charitable? You've suggested they are at the trough; they are making a lot of money off of this through research grants and government spending. Surely some of them are well-intentioned people genuinely worried about the state of the world. Can you give them their due? And what would they say--what would some of those folks say listening to your lack of concern? Guest: Well, you are absolutely right. And it's a vital corrective. And I always try to do what you say and not make ad hominem arguments or question people's motives. I don't always succeed, I must admit. But I like to think I'm not always, generally responding rather than initiating these sort of exchanges. Yes. I think there are a lot of people who have--there are some people who know perfectly well that I'm right and are nonetheless determined because they are on the bandwagon and keep going on. Of course there are going to be some like that. But I think the vast majority of people have not read deeply into climate science. And I've read quite deeply, but I won't claim that I've read deeply enough, or as much as other people. But the vast majority of people who have a strong view on this, whether it's an environment organization, in politics, or in journalist, or even in everyday life, have only scratched the surface. And have somehow equated, in their minds, the fact that climate has changed with a threat. With the fact that it's dangerous. And it's that illusion--that illusion between, when somebody says--so people will often say to me, 'Oh, come on, you've got to admit the birds have arrived earlier this spring.' Therefore we face dangerous future. Russ: 'The icebergs are melting.' Guest: Now, 'therefore' is a gigantic leap. So, I don't think that those kind of people are being intellectually dishonest at all. I just think they've failed to appreciate that there's a difference between climate changing and climate changing dangerously. And, I therefore feel that there's a chance to have a reasonable conversation with such people. Now, of course there are others, who know even more than me and who still remain alarmed. And that's not necessarily because they are corrupt in some way. It's because we all look at the evidence and see what we want to see, to some extent. And no doubt I'm doing the same. When I see a piece of evidence saying 'We reckon now that the was no pause in global warming over the last 15-18 years because if you look at the way sea surface[?] temperatures were measured, once they started using intakes of water into ships rather than buckets thrown over the sides of the ships, they introduced a distortion that appeared to lead to a cooling of the temperatures when in fact it didn't--I look at that and think, 'Oh, come on, you are trying really hard to find an excuse.' Whereas they look at that and think, '[?] See! You guys were wrong.' Now, take another piece of data and I might take their view and they might take our view. So, we are back to confirmation bias. [more to come, 53:23]
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