New Iceage? Much Evidence? - Global Cooling

[jethro]

http://www.gatech.ed....html?nid=62209

I think this may help BFTP?

That doesn't support your claims GW.

"While it’s still hotly debated among scientists whether climate change causes a shift from the traditional form of El Nino to one known as El Nino Modoki,"

"Last year, the journal Nature published a paper that found climate change to be behind this shift from El Nino to El Nino Modoki. Whilst the findings of that paper are still being debated, this latest paper in Nature Geoscience presents evidence that El Nino Modoki drives a climate pattern known as the North Pacific Gyre Oscillation (NPGO)"

"The NPGO, first named two years ago by Di Lorenzo and colleagues in a paper in Geophysical Research Letters, explained for the first time long-term changes in ocean circulation of the North Pacific, which scientists now link to an increasing number of dramatic transitions in coastal marine ecosystems."

What I take from that article is that a couple of years ago a group of scientists identified an ocean cycle which hitherto had been unknown. They published a paper claiming this new discovery had been caused by climate change. That claim is still under investigation and "hot" debate. Whilst still debating the cause of this newly discovered cycle, they are investigating the impact it will have.

No mention of La Nina, no mention of warmer or milder or less dramatic La Nina's. The current La Nina shows no signs of being warmer than past ones, in fact quite the opposite. Weather forecasters put their neck on the block every time they make a forecast, sometimes they're right, sometimes they're wrong; predicting something as chaotic as weather and climate is bound to be open to surprises and mis-calculations. Even large organisations like the MET get it wrong, they accept this and hold their hand up when the promised B-B-Q summer doesn't arrive as expected; personally speaking, I have greater respect for them as a consequence.

[Gray-Wolf]

I'm sorry J' but you can't expect someone to 'tell' you everything? You need to use your own nous and figure it out. With a novel driver evolving in the N. Pacific can you claim all else there has remained the same?

Somehow I can't see it myself?

[jethro]

I'm sorry J' but you can't expect someone to 'tell' you everything? You need to use your own nous and figure it out. With a novel driver evolving in the N. Pacific can you claim all else there has remained the same?

Somehow I can't see it myself?

I expect the scientists involved to be given time to reach agreement before a "hotly debated" cause is accepted as proof for a personally held belief of a layperson.

Not only is the cause of this newly recognised cycle still being debated and therefore not shown to be even vaguely correct, it doesn't refer to La Nina "milding out" in any way, shape or form.

And before any claims are made about climate change impacting upon the ENSO cycle, we have to understand what drives it in the first place - theories upon that abound, from wind to thermal gradient to Solar, to name but few.

If a new study (by one group of scientists) found the Arctic ice loss was driven by some new, unknown phenomena and the study was still being "hotly debated" would you be so supportive? Let's have a level playing field.

[Gray-Wolf]

Maybe we just need be clearer as to whether our posts are our own, unique, understanding of the natural evolution of the impacts we accept as 'fact' and those of 'scientific findings'?

From watching warm water 'currents' (on a sunny day whilst topping up the kids pool) I find it very easy to 'project' how novel forcings will interact with existing 'flow structures' ('understand' in a very vague way you understand?) and so find it very hard to understand how such flow structures would not propagate through the system (with ever reducing impacts) until a new equilibrium is again reached.

Modoki, being centred further west, will surely introduce flow structures to areas not normally 'stimulated' by a normal Nino'. That this interaction is 'done and dusted' by the end of the Nino' is not within my understanding of fluid dynamics and I must therefore dismiss the notion in favour of the perturbations continuing to impact the ocean (N.Pacific) well after the fading of the Nino' that generated the said perturbations (i.e. in the Nina' phase)

Just the ramblings and ruminations of man with casual interests (and not scientific 'proofs') and I'm willing to entertain others folks reasonings as to why this should not be so?

[jethro]

Having our own personal view of things is fine, so long as it doesn't lead to claims of scientific support, when there is none. This is after all supposed to be a science based discussion forum, not a soothsayer's gathering.

[Gray-Wolf]

Very harsh J'?

Are we not allowed to use our own brains here?

If we read this paper and then that paper are we forbidden from trying to figure out how one dose of new info might interact with another new dollop of info?

Are we not to be trusted to do such a thing and speak of it?

Somehow I feel I'm losing sight of what you ,as a mod, find acceptable as posts within these threads?

[Midlands Ice Age]

Hi guys,

I've voted for 'no change' after alot of thought and reading thru' the forum.

To start off with, I do not dispute the fact that the earth has slowly warmed in the last 30 years. To bring ozone into the discussion on global warming is a red herring as I have not heard of many people or scientists who disputed the trouble that ozone was causing back 20 yeqars ago.

But to ascribe all the current warming to CO2 is to ignore all our previous history of warming and coolings. We all are all aware that during the previous major iceages, the global temperatures apears to have dropped by 10c.

Also, we know that during the Interglacial warming periods the temperature was at least 5c higher than it is today. What process caused this to happen then?

Why has the temperature fluctuated so much during the last 1 million years?

It certainly does not appear to be due to man if you look at the longer timescale...... Unless it was from the methane of the millions of wild animals!!!.

No my feeling is that there are longer-term forces at work here, possibly to do with changes in the sun's strength and the interaction with the global oceans, may be not.

The next few years, as is being widely suggested, should give us more insight into the driving forces. My believe is that there are many interactions going on and it will take many more years (of discussions and scientific studies) to get anywhere near the true picture.

I shall be watching the next few years with interest

[claret047]

Hello Folks,

I am a fence sitter as far as whether we are going to experience global warming or entering a new ice age. What I do feel however is that world resources are finite and therefore we shiould conserve as much as we can and the Government should not use fears of Global warming as a stealth tax.

Please see link below re business and others perception.

http://www.dpaonthenet.net/article.aspx?ArticleID=37260

[Essan]

But to ascribe all the current warming to CO2 is to ignore all our previous history of warming and coolings. We all are all aware that during the previous major iceages, the global temperatures apears to have dropped by 10c.

Hi welcome to Net-wx, welcome to the lion's den .....

The range of temperature change varied - the tropics were probaby no more than 1c cooler than today and at some point may even have been warmer.

Also, we know that during the Interglacial warming periods the temperature was at least 5c higher than it is today. What process caused this to happen then?

Earth's orbit varies and as a result, for example, during the last interglacial it was warmer than today.

However, irrespective of this, human activities are now affecting regional and possibily global climate. In the past there weren't 6,700,000,000 humans chopping down forests, plouging fields, building cities, producing pollution, etc etc - all of which affects things like cloud cover and albedo which in term affect the global temperature as well as regional climate.

And then there's the contentious issue of CO2 .... :winky:

[jethro]

Very harsh J'?

Are we not allowed to use our own brains here?

If we read this paper and then that paper are we forbidden from trying to figure out how one dose of new info might interact with another new dollop of info?

Are we not to be trusted to do such a thing and speak of it?

Somehow I feel I'm losing sight of what you ,as a mod, find acceptable as posts within these threads?

I'm simply saying that your claim earlier today that the article on the ENSO changes, supports your claim that we can expect a warming or milding out of La Nina (starting with the current one) is wrong - it offers no support. When I pointed this out to you, instead of answering or offering science to support your views on this, you came back with "it's ramblings and ruminations of man with casual interests".

Using our own brains is all well and good but with the best will in the world, on a science based discussion forum, our thoughts and ramblings amount to nought without the science to support them. If that wasn't the case, then anyone could make whatever spurious claim they like and expect that to be held above everything else. You don't accept that level of discussion about Arctic ice as being valid, why should it be different for the ENSO cycle?

Many folks have made claims about expected recovery in ice levels, you accept none of them because there is no science to support the claim. Thoughts, feelings, expectations, ruminations, call them what you will, they are not valid unless the science is shown to support them, a standard you apply and expect (rightly so IMO).

Your expectations upon the milding out of La Nina's is currently not happening, if in the future it does, I'll be the first to say "yup, you were right" but for now, judging by the current one, it would make sense to accept you were premature in your prognosis.

[Hiya]

Okay some background.

Interest in atmospheric ozone began with O. M. B. Dobson, a British meteorologist. Studies of meteor trails led to the discovery of a region in the stratosphere at a height of about 50 km which owed its high temperature to absorption of ultraviolet radiation by ozone. Dobson invented a spectrophotometric method of measuring its total amount in the air column and in the 1930s set up a chain of ozone measuring stations. Systematic measurements using the Dobson instruments at Argentine Islands (Faraday) and Halley Bay (Halley), were begun in 1957. Measurements were also made at other lGY Antarctic stations including Little America. The interest was that ozone, being produced photochemically at heights of between 20 and 50 km, mostly at low latitudes or, in the summer only, at high latitudes, could be used as a tracer of atmospheric circulation at high levels. It was found that a major increase in total ozone occurs in the course of breakdown of the Antarctic winter stratospheric vortex. Long-term trends, however, seemed to be small, less than those at lower latitudes.

Meanwhile concern had been growing about effects of human activities on the ozone layer which might result in penetration of damaging amounts of ultraviolet radiation to ground level.

The science behind the causes of the depletion I’ll leave to Wiki.

http://en.wikipedia....Ozone_depletion

Wondering about whether it has happened before is irrelevant. IMHO that is.

I have made mention of this some time in the distant past but comparison of the ozone depletion and AGW is like scientific chalk and cheese. About the only similarity is that they both happen in the atmosphere!

[knocker]

I have made mention of this some time in the distant past but comparison of the ozone depletion and AGW is like scientific chalk and cheese. About the only similarity is that they both happen in the atmosphere!

That is very true but unfortunately you are missing the point of the post. And the explanation that you quote was an attempt at trying to be helpful in repsonse to a direct question. Even I, in my ignorance, appreciate there is a difference.Time for me to make my exit from these climate discussions methinks but a final thought ,although this wasn't the point of the original post. AGW tends to make the stratosphere colder which in turn leads to the increse of PSCs whis act as a catalyst in ozone destruction. Ergo the chalk and cheeze tend to be in closer proximity.

Edited October 20, 2010 by weather ship

[noggin]

To bring ozone into the discussion on global warming is a red herring as I have not heard of many people or scientists who disputed the trouble that ozone was causing back 20 yeqars ago.

Hello and welcome. May I just point out that it was I who asked a question about ozone and weather-ship kindly supplied an answer.

If there is any "blame" to be allocated, then it should be at me and not at weather-ship.

I have made mention of this some time in the distant past but comparison of the ozone depletion and AGW is like scientific chalk and cheese. About the only similarity is that they both happen in the atmosphere!

Please see my reply to Midlands Ice Age, above.

It was me who asked for information re ozone and weather-ship was kind enough to supply said information.

[Scottish-Irish Skier]

I’ve been encouraged to join in so here goes. Apologies for not quoting individuals but here’s my tuppenceworth from a read of the thread to date:

The opposing arguments concerning the positioning of thermometers both have validity. Accurate calibration (with regular checking) and positioning of thermometers will of course have a major impact on the absolute temperature measured. I imagine the most pedantic of you who have your own weather station (I include myself here) will regularly check their thermometer calibration (e.g. with the simple ice bucket test - less need of course if it is a traditional Hg variety, rather than platinum resistance/PRT or similar) and will have tried placing it in different positions around the garden to see what happens. Doing the latter may of course reveal quite significant variations depending on locality. This is of course why people are looking at changes through time rather than absolute values – changes should be much less subject to locality than absolute values are.

I regularly calibrate precision lab PRTs and they do drift. Drawing a simple analogy with T in at a weather station, positioning of PRTs within lab equipment can also have a major impact on what pressure/temperature a phase transition is recorded at. Getting, e.g. +/-0.5 C does require careful design combined with patience; I often have to review papers where scientists have not been careful or relied on manufacturer designs without question. Result is garbage, scatter etc.

Of course scientists are not stupid – to get to the positions they are in, they need to be intelligent and most importantly, creative and open minded. However, they are human and regularly do make mistakes. A lot of science is wrong, or at least only partly right; people have to conclude based on what data they have in hand. Often, the slightest oversight can have a major influence on the conclusion. Commonly, such oversights arise because, while being an expert in topic X, an effect related to topic Y influenced things. As the scientist was an expert in X but not Y, they never saw the problem. Advice – do not believe everything you read as gospel, even in very high ranking journals such as Nature/Science. I’ve read a Nature paper, immediately did not believe it, went down to the lab and proved it incorrect over the next week. We told Nature our findings and our ‘peers’ still believed the original paper, saying our conclusion was wrong. I was astounded as we used the simplest chemistry (Gibbs phase rule) to prove the point. End of story is the Nature paper is now thoroughly discredited and our findings vindicated buy numerous independent labs. As is a classic example of the human condition; the original, very eminent author, still says he is sure of the original result but can’t check it as ‘the data discs were lost’. Moral of the story – results are only as good as the equipment and the scientists that used them and some scientists can be stubborn to the point of ignorance, just like Joe Bloggs can be. No dataset/conclusion should be considered infallible unless confirmed by as many independent/alternate methods as possible.

I understand that the UHI effect has been carefully considered and accounted for as well as it can be. This, and the use of change in temperature rather than absolute values, means readings from weather stations over the past few decades, IMO, should give reasonable trends, albeit values probably lie within their own margin of error to an extent. One previous problem was the gaping holes in unpopulated areas where there are not stations, although these can now be filled with satellite data. The main problem is the changes we are seeing are not 5-10 C, but generally <0.5 C. These are very small, and as noted, probably lie within the range of error. There is also the major problem of looking at particular sets and ranges of data. As discussed on this thread; you can conclude quite differently depending on which data you ‘cherry pick’; this is a particularly pertinent problem when trying to reconstruct from proxies when there were no weather stations around; proxies all have their own potential source of error.

While I do not know much about the author nor advocate the robustness of the work, this does nicely summarise the ‘cherry-picking’ data problem in science, in this case for recent atmospheric temperature data:

http://www.masterresource.org/2009/10/a-cherry-pickers-guide-to-temperature-trends/

Do I think the world is cooling or warming? On balance, I believe the world has warmed up a touch in the recent few decades, but I’m not seeing hockey sticks. Are we cooling again – it appears at my house we are a little, at least in the winter, and I’m enjoying the resulting snow, but it’s too soon to say globally. The inherent dynamic and often stochastic nature of the climate makes it extremely difficult to say; I believe it is quite possible that we may see a cooling period just as it is possible that we might stay the same or get a little warmer. When chatting with someone who is utterly convinced one way or the other (often it is for warming), I ask them if they would bet their house on it – the answer is of course ‘no’. Thus even those apparently utterly convinced about global warming (or cooling for that matter), who will argue for it until they are blue in the face, actually still doubt it when it comes to the crunch….

Listen to the fence sitters – they are either clever enough to know they don’t know enough or do know enough and are clever enough to know that they can’t firmly conclude…

[blitzen]

Listen to the fence sitters – they are either clever enough to know they don’t know enough or do know enough and are clever enough to know that they can’t firmly conclude…

Another enjoyable post SS. I didn't understand some of it, but enjoyable just the same. I count myself as a fence sitter in that I am certainly not CLEVER enough to know, it's just that I Don't know. It is so hard to discover which side of the fence one should be sitting on when there are so many articles, papers etc for either pro/ante AGW/GW encompassing claims and counterclaims. I suppose, deep down, I am a believer in natural cycles but, this view can get you shot at dawn in some of these threads! I was reading this article today and I bet you, or I, or anyone else can find another article to counterclaim it! Have a read:

http://scienceandpublicpolicy.org/images/stories/papers/originals/surface_temp.pdf

[Scottish-Irish Skier]

Another enjoyable post SS. I didn't understand some of it, but enjoyable just the same. I count myself as a fence sitter in that I am certainly not CLEVER enough to know, it's just that I Don't know. It is so hard to discover which side of the fence one should be sitting on when there are so many articles, papers etc for either pro/ante AGW/GW encompassing claims and counterclaims. I suppose, deep down, I am a believer in natural cycles but, this view can get you shot at dawn in some of these threads! I was reading this article today and I bet you, or I, or anyone else can find another article to counterclaim it! Have a read:

http://scienceandpub...urface_temp.pdf

Looks to be a good read. I'm firmly in favour of raw experimental data as the best way to monitor, but from a quick scan this article highlights the problems that every measurement scientist faces - getting data which gives an accurate picture of what they want. I expect many climate modellers have never actually worked in a lab/calibrated a T probe. It is very often the case that 'modellers' are very distant from 'measurers'. In my experience, those that can work wonders with long complex equations and statistics are like a bull in a china shop when it comes to the practicalities of actually generating data in the lab/field; their brains just work differently. The great scientists are the ones that can understand/are good at both. There is always great danger in making models/predictions based on data you did not generate yourself; you have to trust that others did it correctly and often they did not...

EDIT:

This made me laugh:

http://www.uoguelph....obTemp.JNET.pdf

I've always felt 'gobal average temperature' to be, even if we can measure it accurately, taken with a large pinch of salt in how much meaning it actually has. To sum up, thermodynamics means that due to the climate being disequilbrium, there is not really a 'global temperature'. We can try to measure an average, but it tells us little in terms of what is happening/what is going to happen even if we get it right. A simple example would be if we had the poles cooling with a new ice age beginning but the tropics comparitively warming for a given reason (some hypothetical combination of factors/feedbacks). Global average temperature suggests business as usual even though the tropics are dying of heat and the north is in a panic due to advancing glaciers. Global average temperature data should be seen for what it is; something climate modellers want as it is a hopefully simple dataset they can try to fit some sort of model to. Unfortunately, thermodynamics does not allow assigning of a single temperature to a disequilibrium system, only at equilbrium can there be a real, fixed, meaningful PTX (pressure, temperature and composition). Thus the focus on global average temperature trends as something that tells us what is happening/going to happen is highly simplistic at best and downright highly misleading at worst.

Edited October 24, 2010 by scottish skier

[jethro]

Welcome to this area SS, thank you.

I enjoyed reading your post, a breath of fresh air!

[ZONE 51]

Yes thanks ScottishSkier great stuff, long and interesting, i think that our part of the world is now cooling, or at least not warming, and most of the world is warming slowly, it maybe balancing out at the moment(on hold?) but the future mostly likely warming and extreme weather, the uk and n-europe is getting the back drift or the ecoe of GW ,melted ice would effect the ocean as we know, this changing the gs/great conveyer/thermo-c , How big affect is melted ice having on the oceans now?

[Devonian]

I’ve been encouraged to join in so here goes. Apologies for not quoting individuals but here’s my tuppenceworth from a read of the thread to date:

...

Listen to the fence sitters – they are either clever enough to know they don’t know enough or do know enough and are clever enough to know that they can’t firmly conclude…

welcome SS.

Can I conclude that you don't rule out the possibility of sustained, perhaps marked (say a 2-4C by centuries end - any more seems unlikely to me), waming of the atmosphere because of the addition of CO2 and other greenhouse gasses from human activities? Or does fence sitting preclude that :winky:

You say the climate is inherently stochastic. Given that, if the Sun warmed by .5% do you think the effect is unpredictable? Or if it cooled by .5%? You see I think there is a reluctance here to accept the reality that it's pretty easy to calculate the effect of adding greenhose gasses - and has been for decades. Given that, I think it's certainly not impossible that the anthropogenic effect on the atmosphere/climate causes the world to experience 'warmest years' several times over the next few decades. With each one I'd find it more and more difficult not to accept the AGW projections. Otoh, if that doesn't happen the fence sitter in me would wonder why. But, I'll be honest, I think the forcing due to anthropogenic greenhouse gasses is clear, and I think we'll see warming due to that - though, of course, the warming due to anthro greenhouse gasses alone is quite small. The only way I can see that we wont see marked warming is other focings cancelling that anthro effect out or that a long established science is wrong or that feedbacks are not as thought. All three seem unlikely to me, that last though is perhaps the most likely (but I wrestle with how a warmer, less icy, world could not have at atmosphere with more water vapour or less ice reflecting radiation).

What say you?

Edited October 26, 2010 by Devonian

[Scottish-Irish Skier]

welcome SS.

Can I conclude that you don't rule out the possibility of sustained, perhaps marked (say a 2-4C by centuries end - any more seems unlikely to me), waming of the atmosphere because of the addition of CO2 and other greenhouse gasses from human activities? Or does fence sitting preclude that :winky:

What say you?

Hi,

No, I don't rule that out. If I did I would be my own enemy.

Maybe ‘stochastic’ is not quite the right word as it implies random probability (e.g. like crystal nucleation from a liquid), but what I mean is it often behaves and a very unpredictable way; not because it is inherently random, but that there are many complex interacting factors involved. Some of these factors we’re pretty sure are involved (e.g. CO₂) but not 100% to what extent, some we think could be involved (e.g. solar cycles, methane), and others which may have a significant influence but we don’t even know they are involved (e.g. paper that will appear at some point in a future journal saying that X is apparently a major factor). In that sense it can appear ‘stochastic’ to us, or at least very difficult to predict.

If the sun’s heat/irradiative output to earth rose/fell by 0.5%, then I would expect we would see an effect; it is the sun that makes our planet comfortably warm and not a cold, icey ball. 0.5% is also a significant change in output; we should be both able to detect that and its effects on global climate.

You say it is easy to calculate the effect of greenhouse gases. Do you mean hypothetically, in the lab, or on the global climate? For the first two, I would tend to agree; the IR absorbance of a gas should be relatively easy to measure/predict for an ideal system (if anyone has a reference for good experimental data on the effect of CO2 at ppm level on the IR and/or UV absorption behaviour of air I’d much appreciate that - plan to look into this a little more). Problem is, the earth’s climate/ocean system is not an ideal system but any means, rather it is a highly dynamic and controlled by many local/external factors. In that sense, we can’t say Xppm CO2 = XTemperature rise. While historically increased CO2 and temperature correlate quite well, there is not a clear and direct relationship. Likewise, CO2 often rises after T has begun to rise. Thus it is clearly not that simple – it would be great if it was!

As for fence sitting…. What I mean is fence sitters are often really annoying to those who have decided either way. However, fence sitters are generally sitting on the fence for good reason; they feel they can’t make a judgment, either because they have not looked into it enough, or because they have looked deeply and feel there is still not enough evidence to say for sure what is happening. Such views are far better than the extremes of either side.

Personally, from trying to keep up-to-date with the debate over the years, I do feel there has been some warming, at least locally to regions (but also some regional cooling too), in that sense I am not anti-GW/complete skeptic. What I am is a skeptic of people saying it is undoubtedly true/not true.

Having worked as a researcher for 10 years now, I know how wrong scientists are sometimes. They may be clever, but they are not all super-geniuses. We actually know very little about the world around us; we are often discovering the completely unexpected, generally by accident. A theory can be accepted for many years, decades even before someone goes, 'oh, wait a minute, look at this' and suddenly the theory falls down.

As for models/future predictions, my colleagues and I have developed a thermodynamic model capable of predicting phase behaviour (e.g. ice melting, liquid to gas transitions….) in multicomponent systems (water, salts, organic solvents, oil, gas and other hydrocarbons). It has taken 25 years of work generating data, tuning the model, validating etc. It is still far from perfect; +/1C is extremely hard to achieve, even for what one might consider very simple equilibrium systems in comparison to the massive, hugely complex disequilibrium of the climate which some believe we can now apparently predict to with less than 0.5 C with ease.

The thing to remember about models is they can only predict with any certainty what we already know. If you don’t know what the answer is, then you have no idea whether your model prediction is true or utter rubbish. Thus models which predict the future of the earth’s climate should be taken with a large pinch of salt; some may be quite correct, at least in the short term, but without hindsight, we have no way of knowing this. This is particularly pertinent right now when the observed changes are small (>0.5 C), we are not 100% sure of the accuracy of past meteorological measurements (e.g. locality, T probe calibration) and we cannot for sure know what error the proxies we use for past climate (before thermometers, e.g. tree rings) actually are because there was nobody actually there to check. If things start to hit 1,2,3 C higher, then we can start to say, 'ok folks, it is getting quite a bit warmer now for sure', but we need a few decades for this.

I am not a climate researcher, but have an relatively in-depth understanding of fluid thermodynamics and limits of measurement/prediction science. This is where my views come from – in the end the same principles apply to all sciences. Personally, I need to find the time to look into the CO2 content/water content of air vs heat absorbance. I use IR spectroscopy regularly and water is a major absorber, CO2 much less so – this I need to satisfy myself about – I’ve always kind of assumed the whole CO2 causes lots of warming as correct without checking out the detailed data. I imagine this of course is well studied, but I always like to check because it is very common that established data has inherent/unforseen problems. I kid you not! My next task.

Should also check out methane in this respect as many claim it is more important than CO2, 10X stronger greenhouse has I see often quoted. Do a google for ‘methane hydrates’. The CO2 people historically ignored this massive source of greenhouse gas lurking close to the surface.

Cheers, SS

[Devonian]

Hi,

No, I don't rule that out. If I did I would be my own enemy.

....

Fair enough SS.

You point out the unknowns. I often wonder if there are unknowns how do we know they mean AGW is less, not more, of a problem?

In a previous post you mention the view we can't measure global temperature. I think it's clear the view we can't measure global temperature is a red herring. Look at the satellite records, they're in lockstep with the surface ones. Look at what the planet is doing. Look at glaciers, or the movements of fish, or bird migrations, or flowing times. Indeed look at the monthly or weekly temperature reports, lo and behold they all coincide with hot and cold spells... This is a warming planet (or, to try and put that better, a planet with a lower atmosphere showing warming trend) and it is a red herring to try to make out we can't measure that - IMO.

Nope, there is enough evidence for us to take AGW seriously. To insure our planet like we do our houses. Early days? Yes fairly. Imo...

New ice age? Any time soon? Not short of a global cataclysm like a huge volcano or a massive meteorite.

[Hiya]

*snip*

I use IR spectroscopy regularly

Cheers, SS

Always good to hear a fellow scientist's take on things, you put it across nicely.

I don't have an IR, after reading your posts in the last few days, use of your IR will probably give you enough data to tackle some things from the bottom down. If I had access to one I could think of a few simple experiments which might put things in perspective.

[ZONE 51]

Great posts those today again.

its really interesting the study's/experiment that some are doing on here, i like that! if i could i would. I think creating small scale models is exciting.

What im wanting to know is what caused warmings in 1400s-1700s? their was many homes with log fires, i dont know, but no exshaust fumes for sure...

[Scottish-Irish Skier]

Nope, there is enough evidence for us to take AGW seriously. To insure our planet like we do our houses. Early days? Yes fairly. Imo...

New ice age? Any time soon? Not short of a global cataclysm like a huge volcano or a massive meteorite.

No time for a long one this morning, but..

I think you misunderstood what I was saying about global temperature. The point of the paper quoted was that there is no single global temperature and attempts to combine all local surface temperature data into a single ‘global’ dataset should be viewed with caution; this just an average and averages can be highly misleading. Problem is, a single dataset is very appealing to modellers – they want something really, really simple to try to model because they can’t model multiple, complex interacting systems with any certainty.

An example of the average problem… The world stops turning tomorrow. One side gets twice as hot, one side gets twice as cold. The average temperature remains the same. Highly simplistic example of course, but it highlights the problem of averages; great care must be taken about interpreting what they are actually telling you.

Thus when I see a plot like this:

http://upload.wikimedia.org/wikipedia/commons/f/f4/Instrumental_Temperature_Record.png

I think hmm…does look quite like there has been warming. But what is the error here? Good convention is to put error bars – but often those who put together such graphs feel it is best to leave these out. Based on measuring temperature of controlled systems with highly precise equipment in a lab environment for 10 years now, I’d put at least +/-0.5 C to cover my a*s. Could well be more. Ok, but wait a minute, that would mean the change is within error? Does not mean the change is not real, but it does mean we can’t be 100% certain.

Must go to work now. Thoughts on glaciers et al later. SS

Edited October 27, 2010 by scottish skier

[Scottish-Irish Skier]

Always good to hear a fellow scientist's take on things, you put it across nicely.

I don't have an IR, after reading your posts in the last few days, use of your IR will probably give you enough data to tackle some things from the bottom down. If I had access to one I could think of a few simple experiments which might put things in perspective.

Making up some gas samples and testing their relative absorption spectra would be great fun - much better than real work .

While looking for more detail on the physics/thermodynamics of the whole CO2 shenanigans to make sure I'm content with concepts (which I'll admit seem strange to me, i.e. that such a small component of the atmosphere could have such a huge thermal effect), I came across this:

http://brneurosci.org/co2.html

Warning - if you believe the earth is warming a bit due to CO2, then this article is fine for you. If you think it's going to get hotter and hotter/turn into a runaway warming scenario, don't read! I have not looked very very closely, but seems to be a good summary of the basic thermodynamics of the wholde thing. Conclusion is that CO2 can cause warming, but only up to a certain point. Seems sensible to me, but more time needed to satisfy myself on each point.

If you are utterly convinced about global warming and know nothing about thermodynamics, do not read this:

http://arxiv.org/abs/0707.1161

Abstract: The atmospheric greenhouse effect, an idea that many authors trace back to the traditional works of Fourier (1824), Tyndall (1861), and Arrhenius (1896), and which is still supported in global climatology, essentially describes a fictitious mechanism, in which a planetary atmosphere acts as a heat pump driven by an environment that is radiatively interacting with but radiatively equilibrated to the atmospheric system. According to the second law of thermodynamics such a planetary machine can never exist. Nevertheless, in almost all texts of global climatology and in a widespread secondary literature it is taken for granted that such mechanism is real and stands on a firm scientific foundation. In this paper the popular conjecture is analyzed and the underlying physical principles are clarified. By showing that (a) there are no common physical laws between the warming phenomenon in glass houses and the fictitious atmospheric greenhouse effects, (B) there are no calculations to determine an average surface temperature of a planet, © the frequently mentioned difference of 33 degrees Celsius is a meaningless number calculated wrongly, (d) the formulas of cavity radiation are used inappropriately, (e) the assumption of a radiative balance is unphysical, (f) thermal conductivity and friction must not be set to zero, the atmospheric greenhouse conjecture is falsified.

I will need to give this a good read. As Scotty used to say 'But Captain, Ya canny change the laws of physics', so if runaway CO2 induced warming breaks the second law of thermodynamics - oocha that is not good news for the GW club.

EDIT:

Seems this article has physicists with their knickers in a twist:

http://www.physicsforums.com/archive/index.php/t-300667.html

Most sensible posts seem to think the paper has some value, but of course there are little mistakes which are easy to pick on without actually greatly changing conclusions and it is really more about our understanding of the 'greenhouse effect' (i.e. why having an atmosphere/oceans makes a planet warmer), which is not directly related to the CO2 induced global warming debate.

Edited October 27, 2010 by scottish skier