Safe Speed Forums

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Interesting... Also interesting to note that Woods Hole recognise the existance of the Medieval Warm Period - something that's been airbrushed out of history by some of the more fanatical AGW enthusiasts.

Have you seen http://mars.jpl.nasa.gov/mgs/msss/camer ... index.html
which is presumably proof that the Martians are also driving gas-guzzlers.

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"Politicians are the same the world over... We build bridges where there aren't any rivers." - Nikita Kruschev

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I won't go on about this, I know it wasn't the original point of the thread and there are about a million other sites you could read about it. But I'll just try to briefly answer a couple of the points on climate change in relation to the links johno1066 posted.

1. Yes, recent studies have shown that plants give off methane. However, this has nothing to do with whether man-made climate change is occurring, though it does call into question the benefit of some carbon offsetting schemes. A warmer climate is likely to cause more methane to be given off, one of many possible 'feedback' effects.

2. I'd be interested to know who's behind that world climate report site, and more importantly where they get their funding. They seemed to have cherry picked facts from various studies. Interestingly, elsewhere on the site they seem to argue that melting icecaps would be no bad thing.

3. At least one of the links refers to possible cooling of northern europe due to slowing of the gulf stream - one of the possible consequences of climate change as melting ice caps affect the salinity of the ocean. Again nothing to do with whether man-made climate change is occurring. It's possible that some parts of the world, paradoxically will become cooler as the rest heats up. It's no argument at all that there is no problem, or that we shouldn't do anything about it.

What it comes down is this:

i) CO2 in the atmosphere is the principal cause of the greenhouse effect, which is what makes our planet hospitably warm.

ii) Increasing the amount of CO2 in the atmosphere increases the effect.

iii) Human activity has significantly increased the amount of CO2 in the atmosphere over the last century.

All of which is basic science, which is why I was amused by the ABD statement, with which I would wholeheartedly agree, but I expect with rather different consequences. Of course the global climate is a highly nonlinear system, with many complex interacting effects. Nobody is entirely sure what the exact consequences of global warming will be, or how much warming to expect, but I don't think it's too much to ask to do what we reasonably can to mitigate the effects. Yes significant natural climate changes have occurred in the past, but the timescales on which these restored themselves was typically tens of thousands of years - the sorts of timescales mentioned in the Martian report!

Having said I wouldn't go on about it, it seems I have, sorry for the rant!



Well I wouldn't want this, of course I recognise that many people rely on their cars so we have to be careful. But I think taxes should be set at an appropriate level that people are gently encouraged to look for other transport alternatives where possible. Despite the apparently escalating costs, the real terms cost of driving has been similar for 30 years.

I seem to have gone on a bit... And it's all horribly off-topic, but why not? It's Tuesday..


Erm... No. The principle greenhouse gas is water vapour - I believe that it contributes something like 97% of the present greenhouse effect. I think that what you meant to say is that CO2 is the principle "forcing gas"... Water vapour is in a state of equilibrium dependent upon local temperature, so if an excess is added to the atmosphere it's balanced out by precipitation in a matter of days. CO2 doesn't work that way, its removal is a very slow (if at all) process so once added to the atmosphere it stays added for a considerable time, which is why it has a sort of "multiplier" effect on warming. The effect is "enhanced" because most of the world's CO2 is dissolved in the sea and as gases are less soluble in warm water than cold, if the seas warm up more CO2 is released... And so on.



That appears to be the case, but it's far from simple...


That is one contention. Problem is, which bits of human activity are the main contributors. Reading sites like T2000 and some of the "eco-nuts" it's assumed that cars are the major culprits, other sites suggest that personal transport contributes less than 0.5% of the CO2 burden.

As I see it, one of the major problems of the extreme polarisation of views about AGW is that there is little reasoned debate anymore - it's become like opposing religions, each with its own view of "how many Angels can dance on the head of a pin" and an absolute conviction that it, and only it, is right.


It looks to me that the GW debate has become stuck on "CO2 etc" and other views, such as GW is related to sun output seem to have been sidelined. The reason that I drew reference to the NASA Martian pictures (which BTW cover a timescale of three years, not thousands) is that there appears to be some form of global warming occuring on Mars - the only (I assume) source of which has to be the sun (unless, as I joked, the Martians have taken to 4x4s in a big way), so perhaps external factors are of considerably more importance than much of the AGW lobby are willing to give them credence.

It both worries and frightens me that massively-impacting legislation is likely to be implemented based on less than half the "story" - and that such legislation, whilst possibly financially and socially crippling may have negligible effect on the climate.



Oops... So have I...

Sorry..

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"Politicians are the same the world over... We build bridges where there aren't any rivers." - Nikita Kruschev

I haven't studied AGW in proper detail, but I've moved from believer to skeptic. Three main factors have caused the position shift:

1) The Safe Speed work has shaken my faith in the quality of science (especially in socio-political areas.) Before the Safe Speed work I would never have believed how bad some of it is.

2) I've seen leading climate scientists on TV saying extraordinarily unscientific things. That makes it look far more like faith than science.

3) I've seen a massive shift (caused by money actually) from the earlier position where science was properly the master of policy. Now in far too many ways, policy is the master of science. Commercial and political interests are having so-called science carried out to support a pre-existing agenda.

I believe we have entered a 'post-scientific era'. Science no longer has the required level of independence.

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Paul Smith
Our scrap speed cameras petition got over 28,000 sigs
The Safe Speed campaign demands a return to intelligent road safety

Pogo, ok I take your point about water vapour. CO2 is thought to be responsible for about 60% of the 'enhanced effect' and stays in the atmosphere for about 100yrs.



Well I think measurements from a pretty wide array of sources, such as ice cores, have shown there's been a fairly rapid rise since industrialisation. I'm not sure what the current major 'culprits' are, from a quick look I can't find anything concrete. The reason transport often comes up is it's one of the few areas in which the UKs emissions are still rising. Cars are of course cleaner now than they were, but that hasn't kept up with traffic growth.

This link talks about the role increased sun activity may have, i.e. up to half the warming could be down to the sun:

http://earthobservatory.nasa.gov/Librar ... ce_04.html

Of course there's nothing we can do about that, whereas we are in a position to influence CO2. The martian pictures only cover 3 yrs, but if you look in the text the changes it is referring to are occurring on long timescales.

I would agree that it can be hard to have a rational debate on this subject, with the fringes of both sides often suffering from a near religious fervour.



I don't think it has to be this way, for example a lot of energy still gets wasted (between 60 and 70% according to one estimate I heard). Of course this will never get down to zero but clearly we can do better. I think there's less doubt on this issue than a lot of people would have you believe. There overwhelming majority of climate scientists broadly agree that that global warming is real and, at least partly, down to human activity.

Which brings me neatly on to:


I couldn't agree more. Conflicts of interest are everywhere, and usually when you are hearing the opinion of a particular scientist or spokesman, you're not told what their organisation is, or where they receive their funding. But in the case of climate science, you find that an awful lot of 'climate change deniers' are funded by the fossil fuel industry.

p.s. what's the A in AGW, anthropogenic?

Yep..

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"Politicians are the same the world over... We build bridges where there aren't any rivers." - Nikita Kruschev

Indeed. And if it wasn't anthropogenic there would be no debate. I don't see much in the way of room for denying that there is some global warming going on, but calling it man made appears to me (as a non-expert) to be an extraordinary leap of faith.

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Paul Smith
Our scrap speed cameras petition got over 28,000 sigs
The Safe Speed campaign demands a return to intelligent road safety

Well I'm no expert either, but if you accept

a) There is some warming going on
b) CO2 causes warming
c) Human activities produce CO2

I don't see how it requires much of a leap of faith.

I suppose the question to ask is if the climate is changing and it is not down to man's influence then what is causing it?

If the global dimming hypothesis is true then we could actually make climate change more likely by cleaning up the air so more of the sun's energy can get through! If pollution had stayed high would we find global temperatures would have stayed lower?

As tomorrow's weather forecast is often wrong how do we know that these climate change models are anywhere near accurate? Weather is an immensely chaotic system and I honestly don't think humans should worry about trying to influence it the 'right' way as much. I think we'd do better just doing sensible things like not wasting energy as much, shopping a bit more locally and recycling materials that are in a shortage. Everyone doing a little bit will have more of an effect than a few people doing drastic things.

We don't appreciate how calm and relatively static the climate has been for the last few thousand years. It is due an upheaval. One large volcano erupting to plunge the earth into darkness and freeze people to death instead of cooking them. I say let's chill and not worry too much

The leap of faith is to suggest that a vastly complex system can be described (and especially predicted) using very simplified terms and arguments. And especially so when mankind's contribution (to global CO2 levels) is pretty much miniscule.

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Paul Smith
Our scrap speed cameras petition got over 28,000 sigs
The Safe Speed campaign demands a return to intelligent road safety

Yes - in the short term. Soot particles in the upper atmosphere are thought to have been mitigating some of the warming effects. But long term things would be much worse. I think we should at least be glad the choking London 'pea souper' is a thing of the past!

The weather is a complex system, in a way it's amazing the forecasters do as well as they do! We just have to go on current trends, best estimates etc. etc. But you're quite right teabelly, I think we can make a fair difference just by being sensible, i.e. at least switching stuff off when we've finished with them etc. Worrying too much won't help. But we should probably worry a little bit.



I'm not sure the contribution is miniscule, CO2 levels have gone up by about 30% on pre-industrial levels, although some of this is likely due to feedback effects. Human emissions in a given period are small relative to the amount of carbon in the cycle overall, but these small amounts do matter, because the natural parts of the carbon cycle (the air-sea exchange and the biological processes) have long been in good balance, at least on the time scales of immediate relevance to humans. Industrial and agricultural activities seem to have significantly tipped the balance of the carbon cycle.

Of course mankind contributes to the amount of CO2 in the atsmosphere there are 6 Billion of us and rising. We all breathe the stuff out of our mouths. I am doing my bit though I don't jog or run anywhere or in fact exert myself in any way so as to keep my breathing out CO2 to an absolute minimum.

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Shooting is good for you and too good for some people.

or...

a) There is some warming going on
b) Exercise generates body heat
c) Body heat radiates into the atmosphere

I don't see how you've missed the blindingly obvious that exercise causes global warming. I'm starting the anti-gym society. Do you want to join?

No! in fact I'm going to the gym tonight. But I think I've produced enough hot air for one day. I'll promise to try to reduce my methane output instead by never eating stewed cabbage.

You see in order to support your conclusion you have needed to drag in all sorts of assumptions, or at best evidence that might be challenged. Suddenly the system isn't so simple, nor the conclusion so obvious.

But please remember I've decalred myself as a non-expert skeptic. I'm not in a position to tell you that you are wrong. But equally, all that material needs justification and proper context.

I'm also minded to note that the more complex the system the greater the risk is that apparent patterns will be assumed to be deeply meaningful, when if fact they are just random data and coincidence.

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Paul Smith
Our scrap speed cameras petition got over 28,000 sigs
The Safe Speed campaign demands a return to intelligent road safety

how about this:
the sun is currently going through a "hot" phase (relatively of course). Some are now predicting that this will end in the next 10 to 15 years and that mean global temperatures will fall as a result.
What are the scaremongers going to do then I wonder?

Go back to worrying about the next ice age, like they did in the 70s.

The next ice age has already started but they work on a ten thousand year cycle usually.

If man is going to live on an unstable thin crust of cooled rock floating on a ball of molten rock at unbebelievably high temperatures in a space of abosolute zero temperature but warmed by a sun of ubelievably high temperatures then he should expect some climate change.

That has been happening for the last 4.5 billion years and it would seem reasonable to expect it to continue for the forseeable future whatever man does.

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Shooting is good for you and too good for some people.