Overplaying the link between climate and weather

[Sunny and Warm]

Al Gore is doing a disservice to science by overplaying the link between climate change and weather

To claim that we are causing meteorological events that would not have occurred without human influence is just plain wrong

• • 

A couple wades through the flooded town centre of Uckfield in East Sussex, October 2000. Photograph: Tim Ockenden/PAWhen Al Gore said last week that scientists now have "clear proof that climate change is directly responsible for the extreme and devastating floods, storms and droughts that displaced millions of people this year," my heart sank. Having suggested the idea of "event attribution" back in 2003, and co-authored a study published earlier this year on the origins of the UK floods in autumn 2000, I suspect I may be one of the scientists being talked about.

Gore is right that it is possible, in principle, to quantify the role of human influence on climate in specific weather events, and that this has to involve probability: how much has human influence "loaded the weather dice" to make a particular event more likely? Such questions can be answered, and because the impacts of climate change are overwhelmingly felt through changing risks of extreme weather, the answers matter. People deserve to know how much climate change is affecting them, and not be fobbed off with banalities like: "this is the kind of event that we might expect to become more frequent."

But the fact that a method exists for establishing whether or not a statement is true does not mean that it is true, still less that anyone has done the study to find out. To my knowledge, formal probabilistic attribution analyses have only been published on two specific events: the 2003 European heatwave and the autumn 2000 UK floods. Both studies found human influence on climate had most likely increased the risk of the event in question, but in the case of the autumn 2000 floods we found a one in 10 chance that the increase was a modest 20% or less. And a follow-up study, just published in the Journal of Hydrology by Alison Kay and co-authors, used the same data to look at factors affecting the risk of a hypothetical flood in spring 2001. They found that greenhouse gas emissions had actually reduced the risk of such a flood: understandably, since springtime floods in the UK tend to result from melting snow, and thanks to greenhouse warming there is now less snow around.

This illustrates an important point: human influence on climate is making some events more likely, and some less likely, and it is a challenging scientific question to work out which are which. Randy Dole and co-workers found no evidence for human influence increasing the risk of the 2010 Russian heatwave, the jury is still out on the Pakistani floods, and has broken up in disarray over hurricane Katrina. So when Gore says: "the environment in which all storms are formed has changed," he isn't actually lying, but he is begging to be misunderstood.

The claim that we are "painting more dots on the dice", causing weather events that simply could not have occurred in the absence of human influence on climate, is just plain wrong. Given the paucity of reliable records and bias in climate models, it is quite impossible to say whether an observed event could have happened in a hypothetical pristine climate. Our research focuses on quantifying how risks have changed, which is a much easier proposition, although addressing all the uncertainties still makes working out these "relative risks" a painstaking affair.

Enthusiasm for doing anything about climate change seems to have given way to resignation that we will simply have to adapt. For the foreseeable future, this overwhelmingly means dealing with harmful weather events that have been made more likely by human influence on climate. What we can't say right now is which these events are, and therefore who is being harmed and how much.

But this question can be answered: in principle, using exactly the same models that are used for weather forecasting, not the much-derided low-resolution variants that are used to predict the climate of 2200. And it deserves to be answered properly: the autumn 2000 flood study took us five years and tens of thousands of detailed simulations, all performed using computing capacity kindly donated by the public. We're hoping to get a bit quicker off the mark in future, but it is frustrating when Gore claims to know the answer before we have even asked the question.

Myles Allen of the Guardian

http://www.guardian.co.uk/environment/2011/oct/07/al-gore-science-climate-weather?CMP=twt_gu

[LithiaWx]

So where do you stop? Was the April 27th outbreak caused by global warming? How about the Joplin, MO tornado? What about the epic cold and heat the past two summers and winters over the southern states? It is way to hard to draw a line between what would have happened anyway and what is happening only because of our influence on the climate. To immediately attribute weather disasters to climate change is jumping the shark. Weather patterns are more likely to be the root of these weather phenomena, if we can draw a direct link between Global warming and these weather patterns then I could start to buy into this theory.

[Sunny and Warm]

So where do you stop? Was the April 27th outbreak caused by global warming? How about the Joplin, MO tornado? What about the epic cold and heat the past two summers and winters over the southern states? It is way to hard to draw a line between what would have happened anyway and what is happening only because of our influence on the climate. To immediately attribute weather disasters to climate change is jumping the shark. Weather patterns are more likely to be the root of these weather phenomena, if we can draw a direct link between Global warming and these weather patterns then I could start to buy into this theory.

These are the damning two paragraphs that directly contradict Rusty, who had a "wow, just wow" snarky moment last night when I dared suggest that weather is weather.

"But the fact that a method exists for establishing whether or not a statement is true does not mean that it is true, still less that anyone has done the study to find out. To my knowledge, formal probabilistic attribution analyses have only been published on two specific events: the 2003 European heatwave and the autumn 2000 UK floods. Both studies found human influence on climate had most likely increased the risk of the event in question, but in the case of the autumn 2000 floods we found a one in 10 chance that the increase was a modest 20% or less. And a follow-up study, just published in the Journal of Hydrology by Alison Kay and co-authors, used the same data to look at factors affecting the risk of a hypothetical flood in spring 2001. They found that greenhouse gas emissions had actually reduced the risk of such a flood: understandably, since springtime floods in the UK tend to result from melting snow, and thanks to greenhouse warming there is now less snow around.

This illustrates an important point: human influence on climate is making some events more likely, and some less likely, and it is a challenging scientific question to work out which are which. Randy Dole and co-workers found no evidence for human influence increasing the risk of the 2010 Russian heatwave, the jury is still out on the Pakistani floods, and has broken up in disarray over hurricane Katrina. So when Gore says: "the environment in which all storms are formed has changed," he isn't actually lying, but he is begging to be misunderstood."

So, what that all says is that scientists have yet to link ANY weather event to AGW or even to plain ordinary climate change. Hopefully, Rusty, Friv, and Skier can figure out that a 10% chance that a modest 20% or less risk exists that AGW caused that flood is extremely low without us having to lead them. It would be nice for a change if the "gang" could just simply acknowledge that freak weather events are likely NOT caused by AGW, but by Mother Nature.

[Sunny and Warm]

So where do you stop? Was the April 27th outbreak caused by global warming? How about the Joplin, MO tornado? What about the epic cold and heat the past two summers and winters over the southern states? It is way to hard to draw a line between what would have happened anyway and what is happening only because of our influence on the climate. To immediately attribute weather disasters to climate change is jumping the shark. Weather patterns are more likely to be the root of these weather phenomena, if we can draw a direct link between Global warming and these weather patterns then I could start to buy into this theory.

I would also say in response to the sentence I bolded of yours is that the continuous jumping of the shark by AGW proponents has definitely eroded public confidence in climate scientists, even though the scientists may not be doing the shark jumping themselves. The average person intuitively knows when something doesn't sound or feel right. I'm not even sure they can fix it at this point, because I mostly hear ridicule of the whole AGW mantra in social situations, usually starting with, "I shoveled 12" of global warming last night", or a rolleyes version of, "AGW causes both warm and cold, as well as wet and dry".

[WeatherRusty]

So where do you stop? Was the April 27th outbreak caused by global warming? How about the Joplin, MO tornado? What about the epic cold and heat the past two summers and winters over the southern states? It is way to hard to draw a line between what would have happened anyway and what is happening only because of our influence on the climate. To immediately attribute weather disasters to climate change is jumping the shark. Weather patterns are more likely to be the root of these weather phenomena, if we can draw a direct link between Global warming and these weather patterns then I could start to buy into this theory.

And that is what I have tried to say, but in response I have been accused of possessing poor reading comprehension skills. La Nina has been the common variable which has lead to the past two years of extreme weather.

Global warming and associated increase in lower atmospheric water vapor provides greater energy to the atmospheric heat engine. The weather which is a manifestation of the physical dissipation of that energy should be expected to be more energetic as a result, especially when contrasted with plenty of cold air still in existence.

Many variable come into play when attributing a weather event to a suite of causes, warm air and moisture are two of them.

The premise is that you can't change a single variable without affecting many others, so we expect weather to be altered as the climate warms.

[LithiaWx]

And that is what I have tried to say, but in response I have been accused of possessing poor reading comprehension skills. La Nina has been the common variable which has lead to the past two years of extreme weather.

Global warming and associated increase in lower atmospheric water vapor provides greater energy to the atmospheric heat engine. The weather which is a manifestation of the physical dissipation of that energy should be expected to be more energetic as a result, especially when contrasted with plenty of cold air still in existence.

Many variable come into play when attributing a weather event to a suite of causes, warm air and moisture are two of them.

The premise is that you can't change a single variable without affecting many others, so we expect weather to be altered as the climate warms.

Do you have some evidence that AGW can cause La Nina? That sounds very far fetched and not plausible.

[Sunny and Warm]

Do you have some evidence that AGW can cause La Nina? That sounds very far fetched and not plausible.

He may not be able to prove that (since the link does not exist), but it has been proven that PDO phase ( a weather phenomenon) heavily influences the ENSO signal on a decadel scale. We are now entering the PDO phase that causes a higher likelihood of Ninas.

[WeatherRusty]

Do you have some evidence that AGW can cause La Nina? That sounds very far fetched and not plausible.

I didn't say that it did.

[WeatherRusty]

He may not be able to prove that (since the link does not exist), but it has been proven that PDO phase ( a weather phenomenon) heavily influences the ENSO signal on a decadel scale. We are now entering the PDO phase that causes a higher likelihood of Ninas.

I would disagree that PDO is "a weather phenomenon". It is a feature of climate which persists in various states for as much as decades of time. That is climate not weather.

[Sunny and Warm]

I would disagree that PDO is "a weather phenomenon". It is a feature of climate which persists in various states for as much as decades of time. That is climate not weather.

would you at least agree with me that the PDO phase "loads the dice" for the weather we see during certain times of each cycle?

[WeatherRusty]

would you at least agree with me that the PDO phase "loads the dice" for the weather we see during certain times of each cycle?

Of course I agree with that. Actually, I think that's the point I have been trying to make with ENSO. Where we differ though, is that I see PDO as a feature of climate rather than a weather event...but I suppose that distinction is a blurry one on some level.

[Sunny and Warm]

Of course I agree with that. Actually, I think that's the point I have been trying to make with ENSO. Where we differ though, is that I see PDO as a feature of climate rather than a weather event...but I suppose that distinction is a blurry one on some level.

agreed

[LakeEffectKing]

Rusty has made his point many times, that hypothisized warming (via AGW) would increase certain "extreme" events over the long term. If he deviated from that a bit, by pointing out an extreme weather event, and subtly implied such an event as a direct result of AGW, then he is only human....wrt having a subconscious confirmation bias....no different then when the 2008 sea ice rebounded significantly and "deniers" "jumped the shark" proclaiming that the entire hypothesis was shot.

And confirmation bias is why the "warministas" tend to consistantly forecast a low sea ice min, and "deniers" tend to forecast high minimums. We are all subject to that "pull".....Rusty and I just percieve the science, and how it is being conducted, wrt AGW/CC, differently.....and some of the political attachments therein.

However, the issues I have with the message often put out by the consensus of AGW'ers, is when an event goes completely opposite of prior prognostications associated with an AGW world (ie...Europe, soon, seeing snowless winters, hurricanes being stronger, more intense, etc...) the default proclaimation is that "it is consistant with AGW...." when they should be saying "...though "xxxx" is behaving differently then what we expect in an AGW world, long term trends should validate our original conclusion, and we need to investigate further if the current trend proves otherwise."

[The_Global_Warmer]

Rusty has made his point many times, that hypothisized warming (via AGW) would increase certain "extreme" events over the long term. If he deviated from that a bit, by pointing out an extreme weather event, and subtly implied such an event as a direct result of AGW, then he is only human....wrt having a subconscious confirmation bias....no different then when the 2008 sea ice rebounded significantly and "deniers" "jumped the shark" proclaiming that the entire hypothesis was shot.

And confirmation bias is why the "warministas" tend to consistantly forecast a low sea ice min, and "deniers" tend to forecast high minimums. We are all subject to that "pull".....Rusty and I just percieve the science, and how it is being conducted, wrt AGW/CC, differently.....and some of the political attachments therein.

However, the issues I have with the message often put out by the consensus of AGW'ers, is when an event goes completely opposite of prior prognostications associated with an AGW world (ie...Europe, soon, seeing snowless winters, hurricanes being stronger, more intense, etc...) the default proclaimation is that "it is consistant with AGW...." when they should be saying "...though "xxxx" is behaving differently then what we expect in an AGW world, long term trends should validate our original conclusion, and we need to investigate further if the current trend proves otherwise."

1. I am not sure who the scientists were who busted hardcore in the summer of 2008. The "deniers" as you state really on blew 2010 as a whole. 2011 wasn't as bad...skeptics were closer to 5,000,000km2. But the extremists like JB busted hard. Unless someone was predicting under 4,000,000km2 it really never was a horrible prediction. This summer's extent ended up between 4.25-4.5 mil km2. I would just say 4.375mil km2 as the average between the top 3. But the thing is...what on Earth would give anyone the idea that the ice is going to recover besides a hope and a prayer?

That is my problem. I am sick of Al Gore and James Hansen. Every discussion I get into gets thrown off track by someone talking from there hip and not there facts and intelligence. And many times it leads back to Al Gore or Hansen or the guys who predicted a total melt out by now.

I am so sick of THE SCIENCE ISN'T SETTLED, WE HAVE SO MUCH TO LEARN."

the outcome is not settled and we have more surprises in store. That is a much much better phrase. I have read so much on this so called lack of science and it is not even close to reality. I am tired of that. The science is pretty damn good..you know, your a professional.

I agree about the hyperbole in the public and general media and politics. But how come the same people who bring up Al Gore do not bring up Rick Perry? I mean Rick Perry is beyond absurd and less qualified then my cat to have any opinion on the matter.

Why can't we make a policy here to stick to science..it's pretty clear what is science and appropriate and not.

[LakeEffectKing]

1. I am not sure who the scientists were who busted hardcore in the summer of 2008. The "deniers" as you state really on blew 2010 as a whole. 2011 wasn't as bad...skeptics were closer to 5,000,000km2. But the extremists like JB busted hard. Unless someone was predicting under 4,000,000km2 it really never was a horrible prediction. This summer's extent ended up between 4.25-4.5 mil km2. I would just say 4.375mil km2 as the average between the top 3. But the thing is...what on Earth would give anyone the idea that the ice is going to recover besides a hope and a prayer?

That is my problem. I am sick of Al Gore and James Hansen. Every discussion I get into gets thrown off track by someone talking from there hip and not there facts and intelligence. And many times it leads back to Al Gore or Hansen or the guys who predicted a total melt out by now.

I am so sick of THE SCIENCE ISN'T SETTLED, WE HAVE SO MUCH TO LEARN."

the outcome is not settled and we have more surprises in store. That is a much much better phrase. I have read so much on this so called lack of science and it is not even close to reality. I am tired of that. The science is pretty damn good..you know, your a professional.

I agree about the hyperbole in the public and general media and politics. But how come the same people who bring up Al Gore do not bring up Rick Perry? I mean Rick Perry is beyond absurd and less qualified then my cat to have any opinion on the matter.

Why can't we make a policy here to stick to science..it's pretty clear what is science and appropriate and not.

At every turn in the progress of science, there is an inherent bias that "we've got it right this time" attitude, because AT THAT TIME, they feel they are on the "cutting edge" which provokes an over-valued confidence level.....yet throughout scientific history, we find that nature humbles us.

Let me ask you this (probably unanswerable).....how much (in terms of percentage) of the climate system, do you think we have yet to have knowledge??? IMO, we have no idea if that is 10% or 90%.....(most of the iceberg, or just the tip). We can make estimations, approximations or assumptions to the given state of the climate system....but what happens when just ONE of the millions/billions of interactions that take place are perterbed to a yet undiscovered threshold that COULD drastically raise or lower it's significance in the overall climate equation?? Does our climate system react the same way at +1.0 C as it would at -1.0C?? And if not, do we know ALL the interactive changes and their respective changes? We can assume some approximations, however, the more chaotic a system, the less predictive that system is.

Just ONE case in point:

We are adding a warming FORCING to the atmosphere (CO2)....but we are also adding a cooling FORCING (aerosols)...but what exact impacts on plant life does this have?? Are they extracting more CO2 from the atmosphere due to warmer weather (due to the CO2 forcing?) How much? Maybe more algae growth in the oceans due to increased CO2 sinkage??? And we could ask an infinite number of questions of the like....with 99.9xxx% most likely being trivial, but it would only take ONE that wasn't, to completely throw off what we THINK we know about the system as a whole, at various states....not to mention, that some of those trivial (ie noise) forcings/feedbacks/interactions could add up to some significant differences, by themselves, to our current understanding....

[Strongbad]

I agree about the hyperbole in the public and general media and politics. But how come the same people who bring up Al Gore do not bring up Rick Perry? I mean Rick Perry is beyond absurd and less qualified then my cat to have any opinion on the matter.

Why can't we make a policy here to stick to science..it's pretty clear what is science and appropriate and not.

Al Gore: Former Vice President (1992-2000), former Presidential candidate, Documentary filmmaker, Best Documentary Oscar winner, winner of the Nobel Peace Prize, multi-hundred million dollar net worth due to founding of Generation Investment Management.

To say anyone does not have the right to state his opinion on a subject is anti-free speech and not applicable in a democracy. If you want a country that limits free speech, it's time for you to leave this one (I hear China, Russia, and Venezuela are beautiful this time of year). It is up to the PEOPLE, and their locally elected representatives, to DECIDE who is right and who is wrong. Al Gore's constant lying is more news-worthy then Perry's climate change positions because: Al Gore has been in the limelight since 1992, has been recognized periodically as a major political and cultural influence. Rick Perry was unheard of outside of Texas until this past year (well, I am sure most people didn't know who he was outside of Texas. But because we all know how masterfully intelligent you are, Friv, I am sure you knew all about him). To try and connect one with the other shows your complete disconnect.

[Sunny and Warm]

Let me ask you this (probably unanswerable).....how much (in terms of percentage) of the climate system, do you think we have yet to have knowledge??? IMO, we have no idea if that is 10% or 90%.....(most of the iceberg, or just the tip).

I recall reading that it was said in the year 1900 that everything there was to know about physics had been discovered. We now know how that turned out in 1905...

So, to answer the unanswerable, I'd say we still have 90% to go. The universe is large and intricate, and the more we know, the more we realize we don't know. If humanity lives long enough, the scope of our ignorance may be known. We'll never know it all.

[Sunny and Warm]

Al Gore: Former Vice President (1992-2000), former Presidential candidate, Documentary filmmaker, Best Documentary Oscar winner, winner of the Nobel Peace Prize, multi-hundred million dollar net worth due to founding of Generation Investment Management.

To say anyone does not have the right to state his opinion on a subject is anti-free speech and not applicable in a democracy. If you want a country that limits free speech, it's time for you to leave this one (I hear China, Russia, and Venezuela are beautiful this time of year). It is up to the PEOPLE, and their locally elected representatives, to DECIDE who is right and who is wrong. Al Gore's constant lying is more news-worthy then Perry's climate change positions because: Al Gore has been in the limelight since 1992, has been recognized periodically as a major political and cultural influence. Rick Perry was unheard of outside of Texas until this past year (well, I am sure most people didn't know who he was outside of Texas. But because we all know how masterfully intelligent you are, Friv, I am sure you knew all about him). To try and connect one with the other shows your complete disconnect.

don't forget that Al also invented the internet ...

[Strongbad]

don't forget that Al also invented the internet ...

How could I forget?! I must have accidentally left that bit of information in my lock-box...

Sunny: What comes after cognitive dissonance and confirmation bias? What is worse? To think that some folks can subsist in an alternative reality devoid of any real-world connections. Haven't numerous polls demonstrated, and numerous Warmists admitted, that those who are more skeptical of the link between AGW and our global climate happen to be more scientifically literate? It's entertaining to watch as some try to say that deniers are the problem, when those who accept AGW happen to know less about science. Is this just another example of how desperate these gung-ho, against all odds, AGW'ers are to maneuver around the obvious?

[Sunny and Warm]

How could I forget?! I must have accidentally left that bit of information in my lock-box...

Sunny: What comes after cognitive dissonance and confirmation bias? What is worse? To think that some folks can subsist in an alternative reality devoid of any real-world connections. Haven't numerous polls demonstrated, and numerous Warmists admitted, that those who are more skeptical of the link between AGW and our global climate happen to be more scientifically literate? It's entertaining to watch as some try to say that deniers are the problem, when those who accept AGW happen to know less about science. Is this just another example of how desperate these gung-ho, against all odds, AGW'ers are to maneuver around the obvious?

At the risk of getting political (Dabize), a significant portion of the AGW crowd is made up of Greenies who think this may finally be the pathway they need to enact public policy changes to prevent things not related to AGW. Every enviro group known to man has lined up behind this "cause" and every one of them use AGW in their donation drive literature, especially the more over the top langauge/claims derided on this site.

[skierinvermont]

Rusty and I have been saying for years on this forum that the correct terminology is that AGW loads the dice towards certain events, which is exactly the terminology that the Guardian article uses.

There has been an effort over the past decade to get the terminology down and to ask the question "How much did AGW load the dice?" not ask "Did AGW cause this single event?" For the most part, most climate scientists understand this important distinction.. obviously Gore does not. If you talk to any climate scientist today they will most likely refer to "loading the dice" not "AGW causes X." Rusty and I have been pushing for this distinction to be made and to ask the correct question "does AGW load the dice?" This guardian article only repeats what Rusty and I have been saying for years on this forum.

I will say Rusty has been perhaps a little faster than I to conclude that AGW is loading the dice towards certain events. I think I have been a little more reserved in concluding this until formal attribution studies are done... and I think the guardian article reinforces that reservation.

Also I would like to point out that the guardian article misrepresentst the work of Randy Dole regarding the Russian heatwave. The Dole paper did conclude that AGW is beginning to load the dice towards such major heatwaves in Russia. The probability of such heatwaves, according to the Dole study, goes from less than 1% in 2010 to 10% in 2100.