Perils and Pitfalls of Event Attribution

By: Dr. Ricky Rood , 6:37 PM GMT on March 11, 2011

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Perils and Pitfalls of Event Attribution

Some of you may have noticed a story that originated in the Green Blog by John Rudolf on the New York Times website (March 9, 2011) about the Russian heat wave in the summer of 2010. The news story reports on a paper to appear in Geophysical Research Letters by Randy Dole and co-authors who conclude that in the historical record there is evidence of similar events of comparable intensity. It follows, they argue, that the Russian heat wave cannot be attributed to climate change – rather it is a very rare event. (Paper at GRL website, NOAA Description of Dole et al. article, Jeff Masters blog and analysis) For a variety of reasons I followed how this story propagated around the blogs and news services for the next 24 hours. It was picked up by many sites including, quickly, by the (according to comment writers on this blog) mysterious Steven Goddard (any more on that story?).

As it happens, I am writing an article for Earthzine with Christine Shearer on how scientists and the media engage each other about extreme events (Shearer blog on WU). When it is ready, I will proudly announce it and provide a link. That article will focus on a sociological analysis of extreme weather and the media. This blog will touch on a couple of the issues we raise in that article, but mostly it will be a scientist's point of view on the discussion of the value of pursuing the attribution of single events to climate change in a context largely described by public discourse.

Event Attribution: A public question that arises after every new extreme event is: can this event be attributed to climate change? At this point in time, I cannot imagine the answer to that question ever being, convincingly, yes. Scientists often rely on the statement: no single event can be attributed to climate change, but this event is not inconsistent with climate change. I have used that answer; perhaps, I repeat the mantra (Pakistan: A Climate Disaster Case Study). On thinking about that answer, it is more than useless. But then thinking about the question, it is, depending on your point of view: a natural question, a naïve question, an ill-posed question, or a leading question.

Why do I say that I cannot imagine the answer to such an event attribution question being convincingly yes?

Dole et al. study attribution, and they do it magnificently. Their strategy is to do a physical, statistical, and process analysis of historical information. If they find like events in the historical data, then that makes it impossible to attribute the event, wholly and solely, to climate change. This implies an odd metric: an event that is “caused” by climate change must be different than any event that has been previously measured. Do we have to have some Day After Tomorrow event where physical principles are suspended and the world moves to a whole new set of behavior?

The probability that looking through all of the observations, all of the history, that you are going to find a “like event” is high. I say “like event,” because there will be some differences no matter what. Of course, it has been hot in Moscow before, so there is some atmospheric pattern that yields “hot in Moscow.” We find like events and then, maybe, the current event is 10 degrees hotter and two weeks longer; it’s a obvious record. But is it climate change?

More likely than a obvious record, there will be another event that is similar, about the same, but not quite. Then it becomes the same question as, was Henry Aaron better than Babe Ruth? Aaron hit more home runs, but there are lots of other differences that experts point to and argue about: length of season, quality of pitching, … . Throw in Barry Bonds and Mark MacGwire; they hit a lot of home runs. Well maybe the physics (or physiology) of Bonds and MacGwire are different? Is climate change weather on steroids?

Suppose you look through the record and find that the current event is 10 degrees warmer and 2 weeks longer. Is it climate change? Do you know whether or not that if you had just one more year of observations, that you would not find out that that next year had a similar hot period. What about similar events in the medieval warm period? The data system was relatively sparse 100 years ago; maybe we just missed the event. So even if we find an event that is more intense, more persistent, then we have the problem - have we really observed the historical extremes? Have we observed all natural variability? This will always challenge the public and political discourse on event attribution - always.

More likely than finding an event that is extraordinarily different, we find an event that’s about the same length of time, but one degree warmer. Is the thermometer good enough? Are the instrument sites good - have they changed? What about the urban heat island? What about regional water management projects? Good scientific investigation and analysis can account for these issues, but in any event they are sources of differences, which as in the Aaron versus Ruth argument, are irreducible. Perhaps an extreme record can be established, but then, would that be climate change?

It is hard to see how playing the game of defining extreme events and then attributing that event to “climate change” can ever be won. It is often possible to isolate with statistical certainty descriptions that the emissions of greenhouse gases have influenced an event, but that represents one of those paths of nuanced explanation. Such nuanced explanation, again, assures there is not a definitive "yes" in the public and political discourse. In fact, it seems like it is a game that necessarily leads to controversy, and controversy is the fuel of talk radio, blogs propagating around the world, and the maintenance of doubt.

But what about that question of attribution? Let’s say you find an event that is rare, that is extreme, but not a new record - does that really say that the event today, right now, is not climate change?

In a very basic, old fashioned way, weather and climate are different descriptions of the same thing. They depend on how we, somewhat arbitrarily, define how we want to organize the observations. Crudely, we average weather to make climate. Since we work from the premise that climate change will be slow, for the most part the same type of weather events will make up the old (natural) climate and the new (changed) climate. Over time, the frequency of events will change, what were rare events in the old climate, might just be less rare events in the new climate. I pose, however, that even in a world that is on average four degrees warmer than today, there will be a seventy two degree, sunny day in the spring in Washington D.C. Do we then march through the days 50 years from now and say, “old climate,” “new climate?” The idea of isolating a single event on a single day or a persistent event and asking if it is caused by climate change – does that make sense? Is it even meaningful given the definition of climate? How did we arrive at the question of climate change being a causative of a weather event?

I want to restate the previous paragraph in a different way. Let’s assume that climate is averaged weather. Then climate is defined by a mean, a standard deviation, and a set of more sophisticated parameters that describe statistical distributions. What we have come to call the natural climate is defined by certain values of the mean and measures of deviations from the mean. The future, changed, warmer climate will have different values of the mean and the measures of deviations. With the presumption that the warming of the climate is incremental, then the majority of the events in the warmer climate will be like the events in the “natural” climate. Therefore, just because a like event existed in the "natural" climate does not mean that the current event is not part of the "changed" climate. There are NOT two climates - a natural one and a changed one - with our job being to determine if we have flipped from one to another. When we say that there will be more extreme events in the changed climate, it does not necessarily mean there will be a relentless unwavering string of records. There will, perhaps, be more events that have been previously rare. But, it is not climate change causing weather events.

As you study climate change, it becomes clear that talking about independent isolated events is not especially productive when trying to address attribution questions. Climate is an average, or perhaps better, an accumulation of weather events. As such it is important to consider how a large number of events act in concert, in correlation, in cohesion.

One other point that I want to make: The practice of isolating a single event and attributing that event to climate change, is one of the most effective ways of opening up scientific investigation to effective scientific criticism. (see Pielke, Sr. et al. 2007) A single-event attribution claim is an open and appropriate invitation to those with knowledge of or interest in local information to investigate the attribution claim. Almost inevitably this leads to identification of more sources of uncertainty, which like the Aaron versus Ruth argument, are irreducible. This necessarily contributes to controversy, and controversy is the fuel of talk radio, blogs propagating around the world, and the maintenance of doubt.

This entire process of event attribution is one place where scientific investigation of the climate interfaces with the media. Therefore, it is also a place where, by definition, scientific investigation interfaces with the political argument. My analysis above suggests that, as framed by the public discourse, the pursuit of the path of event attribution and the explicit or implicit linkage of that attribution to climate change is scientifically questionable. This stands in contrast to the scientific pursuit of extreme events in historical context and the evaluation of whether their frequency of occurrence is changing. Politically or in terms of informing the public, the primary product of the pursuit of event attribution is to build and maintain doubt. The exception to doubt maintenance would be if a definitive, metaphorical smoking gun was discovered. But what is the probability of such a smoking gun being discovered in this process? A different perspective is needed on the role of extreme events in climate and the attribution of such events to global warming. As climate scientists, we have to think about what these studies mean to the body of our field’s communication of climate change.

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Just take my word for it. Haven't you read my well-reasoned and supported theses?


Maybe try googling "thesis" and the spelling of it.

LOL

"Steve-o"



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What method of power generation have any of you here on this blog thought of to replace those nukes? How are you going to make our climate change work for us instead of against us?
Member Since: January 2, 2006 Posts: 127 Comments: 20219
Quoting cyclonebuster:
I hope you can see how safe nuclear power really is now? The whole island of Japan 127 million people may have to evacuate and the USA may have to accept for the first time nuclear refugees. Are we a compasionate nation with the people here willing to accept these people? How long will this condition last? What are the consequences if they return to an island that is contaminated? What cancers will they get? We have to ask ourselves what method of power can we use to substitute for nuclear power?


Seriously...under no circumstances will the entire island of Japan be evacuated.
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I don't want one atom of that contamination in my lungs? How about you?
Member Since: January 2, 2006 Posts: 127 Comments: 20219
How long will it take for the nuclear cloud of death to reach us from Japan? What weather patterns will bring it to us?
Member Since: January 2, 2006 Posts: 127 Comments: 20219
I hope you can see how safe nuclear power really is now? The whole island of Japan 127 million people may have to evacuate and the USA may have to accept for the first time nuclear refugees. Are we a compasionate nation with the people here willing to accept these people? How long will this condition last? What are the consequences if they return to an island that is contaminated? What cancers will they get? We have to ask ourselves what method of power can we use to substitute for nuclear power?
Member Since: January 2, 2006 Posts: 127 Comments: 20219
*sigh*
And the middle school behavior continues...
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Quoting SteveGoddard1:
I do exist, but I live in an undisclosed location due to threats from bloggers of WU.


LOL! It was only a matter of time, I guess...

Although, why SteveGoddard1? Was SteveGoddard taken already?
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Quoting McBill:


Strange that you say it "matters very little to me," yet expend so much effort trying to distance yourself from WUTF. Who knows, maybe the fact that just about everything you post here that is related to climate science can also be found at WUWT is just sheer coincidence. Maybe you and Tony Watts are twins separated at birth. Or maybe you're just another run-of-the-mill denialisto too lazy to think for himself. Actually, no thought is really necessary when your mind is already made up. Aren't I right?

I am wondering, where were those comments with substance to which you refer? The most profound revelation that I've ever read from you is, "We know Nothing! Nothing!'

Must have been a real challenging 4 years for you majoring in Nothing.

Umm, whatever. You can look back years. Or not.
WUWT? I don't visit there so much, but you think I do. WUtever. Again.

Your opinion of myself also matters very little. Think what you want.

And, no, I'll not descend to petty name calling. Not threatened enough, I suppose. But I will ask what the esteemed McBill's contribution ever is, except for the above. *crickets*
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Quoting weatherboy1992:
Still waiting for atmoaggie to give evidence that 'Steven Goddard' exists. That is one of the topics Dr. Rood asked about.

We all know 'Steven Goddard' is a phony, a fake online persona. Only the stupid and gullible believe he is real.
? I don't think I've ever referenced anything from that person.

But, how would you know that he isn't the Mark Twain of climatology? Maybe a professional that wants to post by pseudonym to avoid backlash? Just sayin'. Or he is a sanitation engineer, policeman or artist and has no background in climatology and is quite the phony, indeed. *shrug*

Have any evidence either way?

I dunno what to believe about him. Have read very little of what he posts.
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Quoting JFLORIDA:
They will have no answer weatherboy1992, if its not personal attacks or weird judgmental accusations its nothing. I talk to the person you are accused of being and there is really nothing I can do that will help that. He was a lot better poster than all of them.

They are inept at valid argument and scientific reference. Some just pop in here to harass people then leave.

Atmo used to be a big WUWT / Anthony Watts weather presenter fan but we cured him of that. So he just pops in to offer hip shot morality consulting on a regular basis now. It would be interesting to see his take on something climate or weather related.

I wouldn't let it bother me. Just ignore them.

I am composing a answer to the blog I will post tonight and hopefully Dr Rood will be able to see it. I have been thinking about this a bit and am thankful someone is at least discussing these trends in attribution.
It is true that I used to comment, with substance, more. But found that it was a waste of time. The comprehension was severely lacking almost always. Or, whatever I posted was wrong because I posted it. Only to have JF post about the same thing the next day. Why bother.

But I've never spent much time at WUWT. A couple of you all seem to think that I do, or that if I'm associated with it, I'm less threatening, or something. but think what you will, matters very little to me.

Funny, though, that JF opens with "if its not personal attacks or weird judgmental accusations" and dishes out the same in the very same comment. (Well not funny, but sad. See previous posts.)
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Oh and to say you aren't SSI.

When SSI came on this blog all the time talked about the EXACT same talking points you talk about

AND

Your "new" name was created 4 days after your lovestormsatnight name was banned is all so hilarious.

You just don't feel good unless you are on this site trolling people.

I think it is time for you to move on.
Member Since: September 15, 2010 Posts: 1 Comments: 563
Quoting weatherboy1992:
For HaloReachFan, it seems 'SSI' was gone before HaloReachFan's handle was created. So how does he know about SSI? Why don't you ask how many handles he's had, what his handle was when "SSI" was around, and how many handles he has now.

I see the thug tactics in here and they are disturbing.



No I have had this name since September.

SSI was attacking me personally since this handle was created.

Mike you are trying to play the innocent one when we all know what you have done on this website.

It disgusts me.

You have shown no proof of global warming being man made.

And for that you get this.

NO PROOF
Member Since: September 15, 2010 Posts: 1 Comments: 563
Quoting weatherboy1992:
We have a good example of thuggish denier tactics her on this blog.

A bunch of denier thugs have attacked me, accusing me of being another blogger. That is false.

And it shows how thuggish the deniers are and how weak their case is. Not one denier has given any evidence or made any arguement that "Steven Goddard" is real. They just attack me, because they have no other tactic. The deniers know that "Steven Goddard" isn't real and that he lies. The deniers simply don't care.

I see the tactic here. Anytime anyone asks deniers a hard questions just say "That's something SSI, or Simon, or whatever used to say!" And refuse to answer it, just accuse and make character assassinations.

I am sure the deniers have a lenghthy list of topics and questions they refuse (or are afraid) to discuss. Everytime someone brings up a difficult topic for them, the deniers shriek "It's SSI!" "It's Simon!" and refuse to answer. Thuggish and cowardly.

And all deniers here participated in that. It shows they are of weak character and have no real arguements to make.

For HaloReachFan, it seems 'SSI' was gone before HaloReachFan's handle was created. So how does he know about SSI? Why don't you ask how many handles he's had, what his handle was when "SSI" was around, and how many handles he has now.

I see the thug tactics in here and they are disturbing.



I believe you left your medication on the kitchen table this morning.
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Im going with Sen. Inhofe as he is the "Big" nut in the Squirrel cage
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Quoting RickyRood:
Not that I want to interfere too much, but I am going to advocate a moderation of the buster tunnels, because I don't want tunnels to completely dominate the blog.

I am curious about the Steven Goddard discussion.

Would be interested in Japanese nuclear power versus Gulf covered with oil problem.





The half life of plutonium 239 is about 24,000 years. That's about 24,000 years longer than the half life of petroleum. It's sort of like comparing plane accidents to car accidents, isn't it? Plane accidents are extremely rare, but rarely survivable. Car accidents all too common, but survivable usually.
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Here is a scenario to ponder?? What if that fuel oil were to foul steam turbine condenser tubing and open cooling water heat exchanger tubing at a nuclear power plant?
Member Since: January 2, 2006 Posts: 127 Comments: 20219
Quoting RickyRood:
Not that I want to interfere too much, but I am going to advocate a moderation of the buster tunnels, because I don't want tunnels to completely dominate the blog.

I am curious about the Steven Goddard discussion.

Would be interested in Japanese nuclear power versus Gulf covered with oil problem.





Like are they equally as bad or is one worse than the other?
Member Since: January 2, 2006 Posts: 127 Comments: 20219
GULFSTREAM KINETIC ENERGY PREVENTS THIS MADNESS!

Fire flares up as Japan nuclear plant spews radioactivity

TOKYO %u2014 A fire broke out anew at an earthquake-damaged nuclear reactor Wednesday, a day after the power plant emitted a burst of radiation that panicked an already edgy Japan.

1.
Japan earthquake
1. Updated 19 minutes ago 3/16/2011 1:39:14 AM 00:00 Fire flares up as nuke plant spews radioactivity
2. Millions in Japan struggle without electricity, heat
3. Panic grips Tokyo as radiation levels rise
4. Japan radioactivity could enter food chain
5. Woman, 70, found alive 4 days after tsunami
6.
Updated 44 minutes ago 3/16/2011 1:14:20 AM 00:00 Japan scrambles to prevent nuclear crisis
7.
Time-lapse of aftershocks
8.
Image:
Images of chaos, destruction

Nuclear power plant operator Tokyo Electric Power, or TEPCO, said it is considering dispersing boric acid, a fire retardant, from a helicopter over the Fukushima Dai-ichi plant's No. 4 reactor.

About three hours after the blaze erupted Wednesday, Japan's nuclear safety agency said flames could no longer be seen at No. 4. But it was unable to confirm that the blaze had been put out, and clouds of white smoke were billowing from the reactor, according to live video footage of the plant.

The newly troubled reactor left the Japanese government struggling to contain a spiraling crisis caused by last week's 9.0-magnitude earthquake and tsunami, which are estimated to have killed more than 10,000 people.

Damage to multiple reactors at the Dai-ichi plant sent low levels of radiation wafting into Tokyo, prompting some people to flee the capital and triggering growing international alarm. The reactor on fire was one of four in serious trouble at the facility, home to six reactors. It was idle when the earthquake struck on Friday, but it had a fuel storage tank on top of the building %u2014 an area where spent nuclear fuel is kept cool.

Link
Member Since: January 2, 2006 Posts: 127 Comments: 20219
GULFSTREAM KINETIC ENERGY OR OIL SPILLS?
Member Since: January 2, 2006 Posts: 127 Comments: 20219
Universe Ceiling Cat checks in on the debate's

Meow,,


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GULFSTREAM KINETIC ENERGY OR NUKES?
Member Since: January 2, 2006 Posts: 127 Comments: 20219
Not that I want to interfere too much, but I am going to advocate a moderation of the buster tunnels, because I don't want tunnels to completely dominate the blog.

I am curious about the Steven Goddard discussion.

Would be interested in Japanese nuclear power versus Gulf covered with oil problem.



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Sad News
Every time you bought acid back in the 60s, they'd always tell you it was Owsley.
I never knew that was his first name. I always thought it was Ozley, like Oz.There were all kinds of crazy stories about him. They claim he broke into Dupont and stole chemical formulas for something called STP, which was a chemicall that that gave you a 72 hour trip that Dupont developed for the military.. Probably just an urban legend. Funny that a guy like that would be a skeptic.
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Quoting sirmaelstrom:


Now that you mention it, the Steven Goddard comments do seem awfully familiar...LOL. But I wasn't just referring to him--a lot of other posters sound familiar too.

Whatever...it doesn't matter to me. I never really had any problem with SSI, or anybody else here really. I try to be respectful of everyone here whether we agree or disagree and for the most part everyone is respectful of me as well. Anyone that isn't I simply flag and ignore. I've mostly managed to avoid the personal stuff.

For which you are to be commended.
We need a bunch more of that around here.
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Quoting HaloReachFan:


Like does he really think we don't know it's him.

The whole :) thing gives it away clearly.

And talking about how Stephen Goddard isn't real.

SSI ALWAYS said that.

Nobody else really does.


Now that you mention it, the Steven Goddard comments do seem awfully familiar...LOL. But I wasn't just referring to him--a lot of other posters sound familiar too.

Whatever...it doesn't matter to me. I never really had any problem with SSI, or anybody else here really. I try to be respectful of everyone here whether we agree or disagree and for the most part everyone is respectful of me as well. Anyone that isn't I simply flag and ignore. I've mostly managed to avoid the personal stuff.

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Quoting sirmaelstrom:
№ 59


It is kind of funny how the names seem to come and go but the posts always seem oddly familiar.


Like does he really think we don't know it's him.

The whole :) thing gives it away clearly.

And talking about how Stephen Goddard isn't real.

SSI ALWAYS said that.

Nobody else really does.
Member Since: September 15, 2010 Posts: 1 Comments: 563
№ 59
Quoting atmoaggie:
Funny that only a certain subset comments on it, though that same subset is no less guilty than any other.

(Okay, not really funny, but, umm, typical for that group...but they seem to be blind to hypocrisy.)


It is kind of funny how the names seem to come and go but the posts always seem oddly familiar.

№ 60
Quoting Cochise000:


Now I understand. Thanks for taking the time to post an explanation.


You're welcome.
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Quoting sirmaelstrom:
As atmoaggie said, if he is posting under a new handle he certainly isn't the first and won't be the last.
Funny that only a certain subset comments on it, though that same subset is no less guilty than any other.

(Okay, not really funny, but, umm, typical for that group...but they seem to be blind to hypocrisy.)
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Quoting Cochise000:


Pardon my ignorance, but what is "SSI"? Thanks.


SSI is short for someone who used to post here under the name StSimonsIslandGuy. Apparently he was banned and allegedly posts here under a new handle. I think there's a good chance that's true, since I seem to recall he had been posting here for several years. I have no idea if weatherboy1992 is the same person though; I've seen at least three other handles attributed to him as well so who knows? I just assume every handle is someone different unless otherwise stated. I'd never be able to remember everyone's aliases anyway.

As atmoaggie said, if he is posting under a new handle he certainly isn't the first and won't be the last.
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About RickyRood

I'm a professor at U Michigan and lead a course on climate change problem solving. These articles often come from and contribute to the course.