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JimD

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Real experts versus us.
« on: October 13, 2013, 07:36:58 PM »
I was reading a blog today and came across an interesting dig, by a real expert on AGW, directed at a type of poster(s) found on many forums related to climate change.  It illustrates an interesting point about people who are very interested in highly technical topics like AGW.  It might merit some discussion.

Quote
....Those predisposed to believing climate change who are less scientifically literate, fall for scares about climate changing fast in improbable ways.

Those predisposed to _disbelieve_ who are less scientifically literate, fall for scares about socialists stealing their freedoms in fast improbable ways.

I would surmise that the attitude expressed in this post is more prevalent than many might appreciate.  To a true expert the mis-understanding or misattribution of the state of the science (in either direction from what is known or can be predicted) is equally upsetting.  One sees on blogs like Real Climate the frustration of the moderators with both denialists and their opposite, who extrapolate to climate changes which are not supported by the science, in their somewhat dismissive and/or slightly contemptuous responses to postings.  There is also a trend there for the jargon to become more technical, and thus incomprehensible to the non-expert, over time in a sort of unconscious intellectual intimidation and shutting off of discussion.

I suspect we are all susceptible to this tendency of non-expert but very interested bystanders to exaggerate in the direction our limited understandings lead us (whether for or against).   I try to guard against this natural tendency by discounting almost all news reports and going directly to the sources of research and also to places like Real Climate to get their interpretation of what the current research tells us.  But, like most I suspect, when I have a level of expertise which exceeds the apparent knowledge of those like the Real Climate moderators in some area that impacts AGW conclusions, I feel fully justified in applying that knowledge and reinterpreting their conclusions or extrapolating from them.  After all, a PhD in Physics is a pretty limited subset of understanding how the world actually functions as a whole.  Having had a brother with multiple degrees from MIT (math & physics), a Fulbright scholar, a PhD in math and post masters degree level work in Philosophy (logic) and Economics (yes I did point out the contradiction of the last two), and fluent in 4 languages; I was still astounded at times what he did not know or understand.  Most all of us fall in the range of from a mile deep and an inch wide to a mile wide and an inch deep.  No one is both a mile deep and a mile wide (many, of course, are an inch and an inch).

But the poster I quoted makes a valid point and I try to keep it in my mind and to apply it when I perform my own analysis of what is likely to happen.  I try to always base my thoughts on the foundations of opinion of experts in the areas where I do not have equal or better knowledge.  I do my best to resist taking the worst number from the worst case RCP and assuming that that number is what we base our assumptions on.  This tendency is very prevalent in news reporting of studies and also a common tendency of those who post about AGW's future effects (or lack thereof).  We need to guard against it.

 
We do not err because truth is difficult to see. It is visible at a glance. We err because this is more comfortable. Alexander Solzhenitsyn

How is it conceivable that all our technological progress - our very civilization - is like the axe in the hand of the pathological criminal? Albert Einstein

ChrisReynolds

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Re: Real experts versus us.
« Reply #1 on: October 13, 2013, 08:31:37 PM »
Thanks Jim,

I think that scientist is right.

A case in point on this very forum is the paper by Wright and Schaller, "Evidence for a rapid release of carbon at the Paleocene-Eocene thermal maximum". That paper finds that the release of isotopically depleted carbon at the P-E boundary happened in less than two decades. Because that event is commonly interpreted as being a methane release (isotopically light carbon) the conclusion drawn by quite a few here was that of a massive methane release (1200Gt Carbon), such as that starting in the Arctic Ocean, with 20 years.

However even Shakova has only suggested that the amount of methane available for imminent release from the East Siberian Shelf is 50Gt. And when one reads the whole paper it becomes apparent before the closing paragraphs that, if correct, what the paper describes is a release of carbon that cannot conceivable be from methane hydrates. i.e. it's near instantaneous, taking a couple of decades to migrate into the 60m deep water of the region concerned.

That paper may be right or it may be wrong, it will be years before it's clear what the scientists think - are there challenges in the literature (alternate explanations) or does it get widely cited. But earlier on today I read Joe Romm's take on it, and I came away thinking - he's called it wrong (again). I'm as wary of Romm as I am of WUWT, and I don't believe either intend to mislead, they just have their own agendae.

I'm being careful not to mention names, because I may be guilty of the same misunderstanding sometimes. I know I do say things about the volume trend of PIOMAS with more confidence than is technically correct, but that's my confidence in that system coming through, a personal judgment. The science is complex and it takes years of reading papers to get to a stage where one can way up the merits of new research. Not everyone has the aptitude or time to invest in that. But people have to be wary of falling into the same trap as the denialists.

It's also worth noting that the most popular posts on my blog have been the most pessimistic, and use of words like 'crash' in titles always lead to high page views in those posts. Which is why I avoid those mistakes now. Keep the titles boring and make the content worth reading. The situation is serious, but expecting Hollywood style rapid disasters that unfold within a year or two, or a catastrophe unfolding in a couple of decades is probably likely to lead to the wrong answer.

wili

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Re: Real experts versus us.
« Reply #2 on: October 14, 2013, 12:34:22 AM »
Jim, your quote from RC is by hank, iirc, who is not and does not claim to be an expert on AGW, though he is very good at doing google searches and is generally quite clever if somewhat prickly.

Still, it's an interesting, though unprovable, claim. In my observation over the years, it is people who are most well informed who tend to be the ones most alarmed about AGW, though some are more reticent about stating their concerns in public than others.
"A force de chercher de bonnes raisons, on en trouve; on les dit; et après on y tient, non pas tant parce qu'elles sont bonnes que pour ne pas se démentir." Choderlos de Laclos "You struggle to come up with some valid reasons, then cling to them, not because they're good, but just to not back down."

JimD

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Re: Real experts versus us.
« Reply #3 on: October 14, 2013, 04:52:58 AM »
Well Hank is certainly much more expert than you or I in any case.  Unprovable? Well we could say the statement does not apply to everyone, but other than that the tendency is pretty obvious I would say?

My observations over the years on this subject would not verify yours.  While I do not know any of the top experts on climate science personally I do have some 2nd hand knowledge via a relative who does have some 1st hand.  Other than that I take what they write and say as what we should base our opinions on.  I would say that they, as a group, are very worried and concerned.  Some might say that means they are alarmed, but the only one close to saying that explicitly that I am aware of is Hansen.  Like Chris I discount Romm as he is more of an ideological advocate than a go to expert.  But 'most alarmed' is not a characterization I would agree with.   Folks like Guy McPherson are the ones who fall into the most alarmed category.

Scientists are reticent by training, experience and their professional standards as spending your days following the scientific method is bound to humble you on a regular basis and a tendency to alarmism is going to end up being embarrassing on a regular basis.  If it truly becomes time to panic I expect that many of those scientists will publically say so.  I would hope in any case.

I infer from what knowledge I have on how they think that they generally fall into the camp of those who think that we will never act soon enough to stop this train and as a result we will have to figure out how to adapt to and live with what we have done.   In such a case as that the work they are doing will still be valuable to those who end up using it and thus they want to continue doing it in the most professional way.

But the post was not really about them.  It was about us.   
We do not err because truth is difficult to see. It is visible at a glance. We err because this is more comfortable. Alexander Solzhenitsyn

How is it conceivable that all our technological progress - our very civilization - is like the axe in the hand of the pathological criminal? Albert Einstein

domen_

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Re: Real experts versus us.
« Reply #4 on: October 14, 2013, 01:27:38 PM »
Hansen said that we have a planetary emergency.

Broecker uses similar language.

Mann compared our present path to driving a car without brakes and airbags into wall. And he said that increasing emissions means we're speeding up.

So there are many prominent climate scientists which have publicly stated that they are deeply worried about what's happening. It would be unreasonable that we would not follow expert opinion on such important matter. There are perfectly good reasons to be alarmed.

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Re: Real experts versus us.
« Reply #5 on: October 14, 2013, 09:40:06 PM »
So there are many prominent climate scientists which have publicly stated that they are deeply worried about what's happening. It would be unreasonable that we would not follow expert opinion on such important matter. There are perfectly good reasons to be alarmed.

But not to necessarily assume on hollywood style disasters or certain major catastrophe within a couple of decades - those things require some caveats at least, namely that it depends who you are, where you are, and what happens.

I think it pays to remember that the earth system is capable of abrupt transitions (which previously to the recent paper about the PETM I had always assumed tended to be regional in effect eg due to changing thermohaline or atmospheric circulation, now I may need to revisit that opinion) - and that some abrupt events have happened, albeit relatively minor and little appreciated. Some are happening, more are thought to be capable of happening - and some might surprise us.

I think the background a person brings to the discussion is also important in understand their perspective. I grew up in rural poverty in Scotland - on the very margins of society, and have struggled my whole life simply to remain out of the gutter. When people glibly say "the poor will suffer first and worst" or "high food prices which will mostly affect poorer people" - they may think they are speaking about someone else - but to me - they are talking about me.

I identify more with the plight of those in poorer nations than with the mild discomforts or inconveniences that preoccupy most people in more developed nations.

And so to assert that nothing catastrophic can happen for decades or more, even if it proved to be true in the context of the wealthiest portion of the worlds population living in the most affluent nations - is a statement I disagree quite strongly with. We are already seeing major climate related impacts in some regions now.

Furthermore a lot of the vulnerability in human civilisation is structural which is to say we put it there (resource consumption and population, for example) - it isn't all about climate change. To that extent I agree with JimD in saying about people and how they specialise (or not) - you may be the worlds leading expert on sea ice, and yet not have much appreciation of how hunger drives social insecurity and tips regions into conflict. The world cannot be predicted from single factors or areas of study - much too complex. As nobody is a mile deep and wide - none of us are going to wholly hit the truth individually. Collectively, we might approach some approximation thereof though.

In the end no matter how fast or abruptly or severely you think these impacts will bite, the bottom line is that humanity - whether soon or later - will experience consequences for our actions historically and today that are almost unimaginable. The basic consequences of dumping ever more carbon dioxide into the atmosphere are the simplest science behind climate change and hard to argue with - a planet ultimately too warm for human occupation in the majority of areas currently inhabited today?

Is that not alarming regardless of the timescale you believe it happens over? (and I still view that state as a long term issue, the collapse of civilisation not requiring anything like that level of stress in my view).

Returning briefly to the theme I touched upon about origins - if you've never experienced anxiety about what you will be eating, how you will afford it or find it - maybe it's time to try that, before assuming it's a comfortably distant and remote problem. The chickens only really come home to roost once this stuff gets personal - for most people. Nothing like tasting the problems to focus the mind.

ChrisReynolds

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Re: Real experts versus us.
« Reply #6 on: October 14, 2013, 10:29:25 PM »
Hansen said that we have a planetary emergency.

Broecker uses similar language.

Mann compared our present path to driving a car without brakes and airbags into wall. And he said that increasing emissions means we're speeding up.

So there are many prominent climate scientists which have publicly stated that they are deeply worried about what's happening. It would be unreasonable that we would not follow expert opinion on such important matter. There are perfectly good reasons to be alarmed.

Yes but what are they talking about?

FWIW I agree with both, what we face is dangerous. But we don't face the collapse of civilisation due to a massive methane emission within a few decades, same with sea level and drought. As Hansen has stressed in his recent white paper on runaway GW, the problem is not that we face catastrophe now, it's that we face serious problems down the road, as a direct result of our actions now.

Geologically what is happening is abrupt. In human terms it is slow.

JimD

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Re: Real experts versus us.
« Reply #7 on: October 14, 2013, 10:54:15 PM »
It is certain that many of the prominent climate scientists are very concerned.  But would you ever expect any of them to do what is extremely common amongst the interested amateurs like us and the news media often do?  For example look at the RCP's from the new AR5 report.  What is almost always the figures used from the non-denier viewpoint.

The high number from RCP8.5.  Not the bottom or the median but the highest.  Doing that is not kosher in a scientific sense is it.  But you can almost predict it from much of the news media (Romm for instance - and he knows better, or McPherson who I am not sure does know better) or any number of regular amateurs do the same thing.  To point out that this is not particularly accurate is to invite aggressive counter postings.

And the WUWT's type crowd falls somewhere on the low side of any set of numbers... if they even acknowledge their existence.

It makes the point the poster from Real Climate was making pretty pertinent.  Both extremes justify what they are doing very passionately.  But neither approach is accurate from a scientific perspective and this tendency of non-experts to act this way is likely a significant reason that real experts do not participate in forums like this one in an open fashion - if at all.  We could probably get more contact with and traction from them if we reined ourselves in a bit.
We do not err because truth is difficult to see. It is visible at a glance. We err because this is more comfortable. Alexander Solzhenitsyn

How is it conceivable that all our technological progress - our very civilization - is like the axe in the hand of the pathological criminal? Albert Einstein

wili

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Re: Real experts versus us.
« Reply #8 on: October 15, 2013, 03:39:20 AM »
The higher number is relevant from a risk assessment sense, though.

Engineers want to know what is likely to be the highest level that a river will flood in the next hundred years so they can know how strong and how high to build it so it may last that long.

I think the same thing is relevant here.

I would add Kevin Anderson and Richard Alley to domen's list. Not to mention Shakhova, Semiletov, Wasdell, Box, and many others.

But also note that many speak in darker terms off the record than in published articles. Oreskes among others has noted the culture of reticence among scientists that can be useful in many ways, but that risks seeming to understate the nature of the crisis that is now crashing down around our heads.

It takes insightful amateurs, therefore, to gauge the real level of threat behind the academic prose, and we are certainly very likely to both disagree with each other on that point and likely get it wrong often in either direction.

But in general, with the possible exception of sudden seabed methane release, the last decade and more has seen science confirm many of the worst fears of scientists and layfolk who have been on the saying that things are setting up to commit us to really nasty consequences much faster than most had expected. And right here on neven's site we've been in the front rows watching some of the most crucial consequences: exponential loss of Arctic sea ice, extremely rapid loss of terrestrial Arctic snow cover, apparent shifts in basic patterns of Hadley cells and jet streams, melting permafrost, and reported large eruptions of seabed methane...

So I just want to caution against automatic assumptions that people are just ignorant who are concerned that the crisis is getting out of control faster than are suggested by most in MSM and even from out-of-date-before-they-are-published-and-necessarily-very-conservative-because-of-their-need-for-consensus-across-a-very-wide-range-of-scientists reports like the IPCC reports.

Of course, it's always comforting to smugly say to oneself that those who disagree with me, especially those saying things that sound scary to me, are just ignorant.
"A force de chercher de bonnes raisons, on en trouve; on les dit; et après on y tient, non pas tant parce qu'elles sont bonnes que pour ne pas se démentir." Choderlos de Laclos "You struggle to come up with some valid reasons, then cling to them, not because they're good, but just to not back down."

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Re: Real experts versus us.
« Reply #9 on: October 15, 2013, 05:43:56 AM »
The higher number is relevant from a risk assessment sense, though.

If there is enough confidence behind it - and the resources to back a "safe" approach to moving into the future. I don't think there is necessarily either once you start to look into the later part of the century.

That's just the thing - it's insane to even contemplate RCP8.5 as a future pathway to select, in exactly the same way so many scientists thought we wouldn't put ourselves on track to exceed 2C because that was also insane. We are beyond the realms of risk assessment when you look long term - as far as I can see - we haven't and aren't tending to choose from the set of sane choices as a species.

Of course, it's always comforting to smugly say to oneself that those who disagree with me, especially those saying things that sound scary to me, are just ignorant.

It's comforting to assume everyone else is ignorant whichever way they disagree with you?

I think though really the important thing is to keep an open mind that is willing to consider new evidence and intelligent arguments. The best discussions in these forums occur when people start testing ideas and arguments each each other in a rational and well behaved manner. Sometimes people actually have very similar ideas but come to quite different conclusions from the same information. That may be due to personality, life experience (or lack thereof), different weighting of the factors involved, etc.

An unhelpful discussion is one where someone merely insists upon something without an ability or willingness to support the argument (or at least the ability to admit it is only based upon their opinion or unsubstantiated thinking).

In the methane debate, one gets examples of both. Some people insist that it is categorically impossible for submarine clathrates to make relatively abrupt changes to the earth system, others insist we're facing certain methane catastrophe within years. Without supporting these assertions, neither line in arguing adds to the debate.

I'm quite happy with the improvements to my knowledge from discussions on the forum. As JimD said, nobody can be a mile wide and deep - but exchanging ideas and information can broaden the horizons of all parties involved.

Only by examining the ideas carefully can one do that. Taking methane as a contentious example:

Some people say it can only operate over thousands of years - which I think credible for deep water clathrates, as it takes a long time to mix heat down into the ocean.

Arguments against the rapid release of shallow water clathrates seem to be either that a) there is no such thing as shallow water clathrates or b) there is no way the heat can mix rapidly enough into the deposits. I disagree on both counts, as a) I've seen papers from different scientists substantiating the existence of these in the Arctic and b) I'm unconvinced by ideas that the only way to move heat downwards is conduction through the seafloor - I think the system is more dynamic than that, and various processes could act to provide mechanisms for abrupt release (not gigatonnes within only a few years though, I hasten to add - I can't currently stretch my views so far as to include the insane figures suggested by the recent PETM paper).

But the basic point is - even though in the end I still disagree with plenty of people on my thoughts - I can point at things I've learned from reading around the subject and from informed discussions on the forum - and consider that immensely valuable - regardless of the expertise of the person involved (the credibility and evidence supporting their arguments is sufficient for me).

Finally - when it comes to real experts vs us - I'm not sure the difference is as big as people think in terms of alarmism. We might be more likely to vocalise opinions, to rush to conclusions, to make basic mistakes in how we do so - but there are still similar concerns represented amongst experts (although I don't communicate with enough real experts to make any statistical comparisons with the population here).

Where the difference does arise - is the real experts - the people with the expertise, resources and connections - are overwhelmingly the people who are advancing our knowledge in these areas. Our role on average is arguably is more to do with making sense of it from the perspective of the layman - and communicating that to those with less information - passing the knowledge down the chain, as it were (preferably as uncorrupted as possibly).

wili

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Re: Real experts versus us.
« Reply #10 on: October 15, 2013, 11:53:48 AM »
"we haven't and aren't tending to choose from the set of sane choices as a species."

That is certainly the case.

I agree with your discussion of the value of dialogue, and this is exactly why I am wary of someone coming up with a bromide that seems to paint everyone with a view that seems more extreme than one's own as necessarily coming from a point of ignorance. It's not likely to make for good, honest discussion if a set of people are coming to it with the assumption that anyone saying, for example, that things are a lot worse than the latest IPCC report suggests are simply ignorant.

"A force de chercher de bonnes raisons, on en trouve; on les dit; et après on y tient, non pas tant parce qu'elles sont bonnes que pour ne pas se démentir." Choderlos de Laclos "You struggle to come up with some valid reasons, then cling to them, not because they're good, but just to not back down."

JimD

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Re: Real experts versus us.
« Reply #11 on: October 16, 2013, 06:44:32 PM »
Wili

Quote
Of course, it's always comforting to smugly say to oneself that those who disagree with me, especially those saying things that sound scary to me, are just ignorant.

Quote
I agree with your discussion of the value of dialogue, and this is exactly why I am wary of someone coming up with a bromide that seems to paint everyone with a view that seems more extreme than one's own as necessarily coming from a point of ignorance. It's not likely to make for good, honest discussion if a set of people are coming to it with the assumption that anyone saying, for example, that things are a lot worse than the latest IPCC report suggests are simply ignorant.

Perhaps you are personalizing this and it does not mean how you seem to have taken it.  I don't think anyone is calling anyone ignorant.

A major part of my professional career activities was spent as a kind of risk assessment specialist.  I received substantial post-degree training in how to perform such assessments in the real world and subsequently spent many years engaged in such activities.  Many times my life and those affected by my decisions depended on my getting the assessments correct.

The person performing a risk assessment is seldom the preeminent expert in more than one aspect of an assessment.  And almost never in two aspects.  All assessments as long as we are talking about complex issues) will, of necessity, cover a wide range of factors the knowledge of which would necessarily cover a number of areas of expertise.  This is why risk assessment is normally conducted by a team of people of varying areas of knowledge.  Risk assessments based upon one persons opinion are ... risky.

When one has no choice but to make the call oneself it is imperative that they remain disciplined in staying within their limits.  And deferring to others who's knowledge is more expert (trusting them to be right) is difficult but essential.  This does not, of course, always work and I have a couple of personal failures I can directly attribute to choosing to follow the advise of others when making a decision when my gut told me they were wrong.  But it is like playing in Vegas, your gut feeling is going to lose to the House on average. 

A proper risk assessment does not always take the high or the lower limits based upon one's personal opinion of the issue at hand.  This is what Hank was talking about.  The non-experts  tend to do this and he was pointing out the problem.

Risk assessment in-itself is an area of expertise.  It is very difficult to do well, often requires a substantial team of experts, and, depending on the issue being worked, can require significant mathematical calculations.   This certainly is true of AGW.  When the non-risk assessment expert interested amateur performs a one-man off risk assessment of AGW he is on shaky ground. 

I am not aware of any risk assessment having ever been done on the AGW issue that I, from my background, would consider to have any validity.  To perform one would require a number of the prominent climate experts to take significant time away from their research and be put on a team chaired by a top level risk assessment expert who specializes in evaluating complex scientific issues.  The team would also have to include experts from a wide range of non-climate areas of expertise.  I don't think that has been done and I doubt it will be done. 

If something has a 5% chance of happening and it is very bad we need to take action.  If it is not bad at all we can ignore it.  Almost everyone grasps that.  But if there are 4 things that have a 5% chance of happening that are really bad and there is one thing that has a 50% chance of happening that is good and they all interact with each other the problem is no longer simple.  If you have 5 things which are really bad that have a 5% chance of happening but do not positively feed each other, but all 5 have to happen for disaster to happen you do not actually have a high risk.  The permutations are endless.

When all of us here on the forum perform our analysis and assessments we need to keep in mind Hank's admonition.  We are not just interested amateurs at climate science we are also interested amateurs at risk assessment of climate science (I include myself in that group as I am in no way competent to do the risk analysis for AGW).  And it is certainly true that an expert climate scientist who has decided he understands the risks of AGW is also on shaky ground as he is making the common error of the expert mistaking that he is an expert in everything.   
We do not err because truth is difficult to see. It is visible at a glance. We err because this is more comfortable. Alexander Solzhenitsyn

How is it conceivable that all our technological progress - our very civilization - is like the axe in the hand of the pathological criminal? Albert Einstein

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Re: Real experts versus us.
« Reply #12 on: October 16, 2013, 07:40:14 PM »
I am not aware of any risk assessment having ever been done on the AGW issue that I, from my background, would consider to have any validity.  To perform one would require a number of the prominent climate experts to take significant time away from their research and be put on a team chaired by a top level risk assessment expert who specializes in evaluating complex scientific issues.  The team would also have to include experts from a wide range of non-climate areas of expertise.  I don't think that has been done and I doubt it will be done. 

If it's even possible. I'm not convinced just doing it only with climate science aka IPCC has really shone. Try adding even more experts and papers and information into the mix? There are plenty of organisations that have attempted to do these sorts of things (if on a smaller scale), but given the uncertainties over even the input data for a risk assessment?). So many assumptions must be made to support any specific scenario that it's difficult to see even where you could even derive a sensible scenario for risk assessment.

If something has a 5% chance of happening and it is very bad we need to take action.  If it is not bad at all we can ignore it.  Almost everyone grasps that.  But if there are 4 things that have a 5% chance of happening that are really bad and there is one thing that has a 50% chance of happening that is good and they all interact with each other the problem is no longer simple.  If you have 5 things which are really bad that have a 5% chance of happening but do not positively feed each other, but all 5 have to happen for disaster to happen you do not actually have a high risk.  The permutations are endless.

Speaking of perceived risk - this is one of my favourites:

http://io9.com/5839058/why-youre-more-likely-to-die-from-a-meteor-strike-than-a-lightning-strike


It isn't unusual to see people get worried when lightning is nearby - even though the probability of them dying from something hitting the planet from space is substantially higher. We don't do well with abstract risk. Abrupt climate change is somewhat like that - except we do (or did) actually get a chance to influence the outcome (another important thing about risks - and where lots of people worry about irrational things, given they can't affect the outcome in question).