EPTw
Poll: Do you think we should discuss Climate Change @ TL?
Yes, I think it is interesting. (958)
72%
No, it's not the right place. (188)
14%
No, it's not interesting per se. (186)
14%
1332 total votes
No, it's not the right place. (188)
No, it's not interesting per se. (186)
1332 total votes
Your vote: Do you think we should discuss Climate Change @ TL?
(Vote): Yes, I think it is interesting.
(Vote): No, it's not the right place.
(Vote): No, it's not interesting per se.
Hi everyone,
while I am a fairly new TL poster I am a vivid TL fan for all things from LR to general discussions to Gliders beautiful drawings. What I do find amazing is the ability of you guys to use this place to discuss everything from the most simple to the most complex questions.
So, here is my proposal: I am a - comparably young - physicist with a PhD in geosciences and work in one of the world's most renowned climate research institutions. I have fought many a battle in a variety of internet fora concerning classical Climate Change Denialist arguments, always in the defensive. I would like to propose a new , more offensive approach. I have also encountered many non-experts who are challenged by the denialists propaganda that is propelled by professional PR institutions, backed up with a lot of money. While I cannot counter that, here is my proposition:
You guys can come up with a bunch of sceptic arguments that you are not so sure how to handle, and I will come up with a - hopefully - scientific answer to what the science in that case is. I will carefully discriminate between scientific assessment and potential political responses (some thing that denialists usually dont do, which makes the discussion so exhausting).
To make this work, I need
a) feedback if you think its a good idea.
b) questions (either her or via pm or live? in a chat)
I will add in most of the arguments that I believe are relevant into the OP and my answer.
So, I am really interested to see the response from this forum (and I hope that this is the right place to ask for that feedback). Again, I do not have a political agenda nor am I in a political party of any sort. I am a scientist who is annoyed that a lot of precise science is contorted in media and society due to influental societal agents with a lot of PR ooomph °
DISCLAIMER
This are "internet forum" level answers, not written in a style and precision I would use for scientific argument in a paper, due to time constraints in answering them.
Hope to read you soon,
W
EDIT:
have a look at the arguments and their rebuttal here:
http://www.skepticalscience.com/argument.php?f=taxonomy
its only a website, but they link quite consistently papers and further literature to their points.
EDIT:
On December 13 2011 07:20 DreamChaser wrote:
I think it would be just you (OP) smashing everyone i don't think there are many who would be able to keep up with your amount of knowledge in this field.
I think it would be just you (OP) smashing everyone i don't think there are many who would be able to keep up with your amount of knowledge in this field.
That would not be my idea.
The majority is trusting science /scientists anyway, a loud minority does not - on purpose with their specific reasons -, I just would like to adress the small minority that is confused. no intention to smash anyone. So perhaps, as suggested, I should rephrase it: I would like to get into discussion with scepticists to help them fight denialists
Everything down from here is a selection of comments or questions that came up during the thread + my answers. I did only include those questions that could be of general interest, or at least my subjective selection thereof.
man made global warming probably exists, but it is not nessessary to take any direct action stopping/delaying it, as the finite resources of the earth make it impossible to cause any real harm to humankind.
that is a weird argument, because it arguably wrong in other cases (see Uran or Plutonium for simple example or CFCs and ozone depletion) and also simply wrong, if we burn all carbon from gas, oil, coal (!) and oil sand (!) we will change the Earth#s climate significantly.
anyway, nobody cares about it because of financial trouble in the world.
true but not the point here.
another point: im AGAINST all kinds of subsudies to create ethanol or any other form of biofuel, because it literally KILLS people by the millions (rising food prices,...) and generates just 1.5 times the amount of energy used to produce it!
this is a controversial point in science as well. It is necessary to think of new mobility solutions that are sustainable and that do not involve fossil fuels. at the same time an overcrowded planet with shrinking agricultural area has to set priorities ... it is so far unclear to me if you can justifiable speak of killing people by the millions, rising food prices are also heavily influenced by the financial markets.
On December 13 2011 07:27 Abraxas514 wrote:
While there is no denying that change is inevitable, the real problem is proving that this change is bad.
I understand the concept of rising oceans reducing habitable landmass, but what about the increased rain? Wouldn't that help many places get more freshwater/grow more plants/generate more electricity?
While there is no denying that change is inevitable, the real problem is proving that this change is bad.
I understand the concept of rising oceans reducing habitable landmass, but what about the increased rain? Wouldn't that help many places get more freshwater/grow more plants/generate more electricity?
the increase in rainfall is mostly over oceans and will not help agriculture in most regions of the world. some regions (.i.e. mediterranean sea) will see significant precipitation reduction for a warmer climate. I wholeheartedly agree with the first part of that statement (and I would be happy if people come up withe more positive correlations of increased global temperature, I would like to finally buy a car
And global temperature rising/carbon emissions. Many more people die in impoverished countries from being too cold rather than being too hot.
I simply dont have the numbers to conclusivelz answer that. In europe the number of deaths due to hot spells is higher than the toll for cold winters, it might be different in poor countries but I doubt that because they tend to be warmer anyway.
Hotter temperatures and increased carbon content in the air means that crops grow faster, and all plants have better living/developing conditions (easier to grow vegetables, can farm herbivore animals easier).
that is a good point and is heavily discussed! the increased productivity due to carbon content will be offset in many agricultural regions due to decreases available rainfall. the argument that we will be able to grow more stuff in the high latitudes when it gets warmer is also flawed because the amount of sun up there will always be less than in the current agricultural regions, even if it gets a little warmer.
hope that helps a bit! science is a process, not a solution.
On December 13 2011 07:48 FoeHamr wrote:
I think that climate change is probably happening, but we don't impact it as much as a lot of people seem to think. Its very possible that global warming is happening, but are we really affecting it that much? I'm pretty sure that the earth simply has cycles were it is warmer and some where it is colder - like the ice age. There was no cars, electricity or technology back then and somehow the Earth's temperature drastically changed. You obviously know more than I do about it, but that's just the opinion I have made based off of my current knowledge.
I think that climate change is probably happening, but we don't impact it as much as a lot of people seem to think. Its very possible that global warming is happening, but are we really affecting it that much? I'm pretty sure that the earth simply has cycles were it is warmer and some where it is colder - like the ice age. There was no cars, electricity or technology back then and somehow the Earth's temperature drastically changed. You obviously know more than I do about it, but that's just the opinion I have made based off of my current knowledge.
This is good scientific thinking. There is a lot of internal climate variability on decadal time scales, longer scales are usually driven by external effects.
Scientist look at how Climate reacts to perturbation of its forcing, i.e. changes in solar activity, atmospheric composition (volcanoes) . We then analysed if there were such perturbations in the 20th century besides man made Co2 changes. As of now, we do not know of any other perturbation that could explain the climate variation.
On December 13 2011 07:37 ~SiC~ wrote:
How is it that if you take real empirical evidence it shows that with the Urban Island effect aside, there is actually no variation of climate or rise in temperature if you look at data that shows information going back further than 100 years? The largest ecological effects the planet has ever had happened previous to mans existence, being the introduction to oxygen to the atmosphere and the ice ages, and we could never compete with the vasts amounts of extinction or devastation either of those events caused.
How is it that if you take real empirical evidence it shows that with the Urban Island effect aside, there is actually no variation of climate or rise in temperature if you look at data that shows information going back further than 100 years? The largest ecological effects the planet has ever had happened previous to mans existence, being the introduction to oxygen to the atmosphere and the ice ages, and we could never compete with the vasts amounts of extinction or devastation either of those events caused.
Hi Sic, good to hear you for you show a few of typical sceptic / denialist arguments. Let me answer them one by one, without the need to pick a fight!
Concerning temperature evolution: you mix many points. The Urban Island Effect, i.e. cities are warmer than countryside: a new evaluation by a group of nobel prize laureates that have NOTHING to do with climate science and that have been paid by the Koch brothers (who fund climate denialist science) have shown, that Earth is warming. The essentially got the same result as the classical reconstructions. See for example http://www.bbc.co.uk/news/science-environment-15373071
The long termin evolution: it is clearly true that Earth has seen a lot of climate changes. Climate reacts to dominant forcings. Nowadays, thats us. In the past it was Volcanic Eruptions, Orbital Changes (ongoing), Sun strength variations, continent movements, extinction events +++ The speed of our Co2 perturbation is unrivalled, though. Past changes strengthen the scientific consensus that a strong change in atmospheric composition will lead to a changed climate.
> Real Denialist here, with my denial coming from actually working with the UN on environmental research and realizing that you are forced to publish only facts supporting global warming, and if anything contrary is discovered you lose funding, or get research ignored.
That is bad that you made these experiences. I know that the UN process of producing political documents is political (sic), but the underlying science is independent. I am involved in the ongoing IPCC process from a quality management perspective (as an outsider, I do not have to publish, yeah), and I assure you, that so far nobody was enforced to write anything except the scientific assessment of what we believe is true.
On December 13 2011 08:01 All.In wrote:
If carbon is one of the things affecting world climate wouldn't 1 giant volcanic eruption release more carbon into the atmosphere then all of the vehicles that run on gas have released to date? I heard a number somewhere that 1 large volcanic eruption would contain more harmful carbon and gases then 100 years of vehicles that burn regular fuel.
If carbon is one of the things affecting world climate wouldn't 1 giant volcanic eruption release more carbon into the atmosphere then all of the vehicles that run on gas have released to date? I heard a number somewhere that 1 large volcanic eruption would contain more harmful carbon and gases then 100 years of vehicles that burn regular fuel.
its not true. the amount of volanic co2 is negligible, the carbon is usually big enough to settle soonish (years). volcanoes have immediate cooling effects in the order of 0.5 deg global (pinatubo) or even up to 5 degrees (yellowstone type explosion, we dont want that °.
it is a well made point though, that strong volcanic eruptions could give us a few more decades time to adjust because warming would be slower for a while.
On December 13 2011 07:53 Buubble wrote:
I don't care - our money is better spend on building infrastructure and eliminating disease. It is better for 2012 india to build a coal plant today than to build solar panels. Based on the precipitation of that wealth and well-being created today by building the coal plant, it is also better for 2112 india to build a coal plant today rather than solar panels. They will be much more wealthy in the future and able to deal with the +.0001 or whatever degree change caused by the coal plant.
I don't care - our money is better spend on building infrastructure and eliminating disease. It is better for 2012 india to build a coal plant today than to build solar panels. Based on the precipitation of that wealth and well-being created today by building the coal plant, it is also better for 2112 india to build a coal plant today rather than solar panels. They will be much more wealthy in the future and able to deal with the +.0001 or whatever degree change caused by the coal plant.
that is a complex topic and a justified way of thinking about it. the problem is, as some has mentioned, that the cost of strong climate change will most certainly not be linear (as in many people live close to coastlines, precipiation changes will influence agriculture on a global level). it is there not only a cost-benefit analysis but also a cost-benefit-risk analysis, that societies should do around the world.
i agree that the amount of "staatlichkeit" (dont know the english word, something like strength of the state) is decisivie for the ability to cope with climate change. if we can increase that today, we should probably do it. it is still useful, from a risk point of view, to think that a combination of adaptation (your example) and mitigation (we prevent it from happening) and not a neither / or will be the optimal way for society.
On December 13 2011 08:10 InDaHouse wrote:
A simple question for OP. How could we (mankind) make so huge impact on climate in very short time?
A simple question for OP. How could we (mankind) make so huge impact on climate in very short time?
by burning carbon that has been accumulated over many millions of years and been stored in fossil fuels. the earth#s carbon cycle is in a fragile equilibrium, by releasing energy in an incredible fast manner, we do impact climate in an unprecedented speed. hope that helps!
- > off for today, sleep and work, tomorrow Ill be back
On December 13 2011 08:11 bonse wrote:
Climate "changes" happened all the time throughout the earth's existence. More exactly, climate was never static, being constantly influenced by a myriad of factors like sun's activity, biomass and so on. There were ice ages and hot ages alternating all the time. To believe that humanity has more influence on the atmosphere than the sun, the oceans, the forests... that's quite a lot of arrogance. Let's face it guys, we are pretty much insignificant.
You tell me, what percentage of CO2 released daily in atmosphere comes from natural causes?
Climate "changes" happened all the time throughout the earth's existence. More exactly, climate was never static, being constantly influenced by a myriad of factors like sun's activity, biomass and so on. There were ice ages and hot ages alternating all the time. To believe that humanity has more influence on the atmosphere than the sun, the oceans, the forests... that's quite a lot of arrogance. Let's face it guys, we are pretty much insignificant.
You tell me, what percentage of CO2 released daily in atmosphere comes from natural causes?
see http://www.esrl.noaa.gov/gmd/ccgg/trends/
the carbon cycle has been in equilibrium for millenia. now we emit a lot of co2. if you do the math and add all sources and all sinks of co2 you will see that at the moment we are in a plus that leads to the increase in concentration. this increase matches athropogenic co2 exactly. relative simple math compared to other effects in this discussion
On December 13 2011 08:22 JinDesu wrote:
dabbeljuh - I was informed that climate change does not mean "global warming" in the sense that everyone gets warmer. I was under the impression that climate change means the global temperature average increases, but that this average is taken where the equatorial areas become significantly warmer, while other parts (I would guess the poles?) actually drop in temperature at certain parts of the year.
In essence, climate change as it is progressing, will cause more of a extremes of climates - not a nice balmy warming of the earth. How accurate is this?
dabbeljuh - I was informed that climate change does not mean "global warming" in the sense that everyone gets warmer. I was under the impression that climate change means the global temperature average increases, but that this average is taken where the equatorial areas become significantly warmer, while other parts (I would guess the poles?) actually drop in temperature at certain parts of the year.
In essence, climate change as it is progressing, will cause more of a extremes of climates - not a nice balmy warming of the earth. How accurate is this?
hi jindesu.
it is true that global warming is not uniform. it is also simple to understand: earth is varying differently in different regions. If we know put the literal hammer on top of the atmosphere (co2), the system will answer stronger in regions of stronger variability than in others. additionaly, some regions as the poles have regional feedbacks, i.e. if it gets to warm summer (not winter!) ice will melt in the arctic ocean, making it even warmer there.
therefore the strongest signal of global warming will be polar amplification, for a global temperature rise of 2-3 degrees we will likely have a polar warming of 6-10 degrees. the warming is also inhomogenous due to topography and circulation changes (its really climate change, not only just warming). these effects are harder to predict and still not completely understood.
climate change might for example lead to warmer winters in europe in general but more extremely cold winters, as an example of nonlinear effects. these specific things are part of the scientific discourse right now.
On December 13 2011 08:32 etherwar wrote:
I haven't done too much research in the field myself so forgive my ignorance. I think it would help if you outlined the major contributors to global temperature average. I have heard a lot about water vapor dwarfing CO2 as a mitigating factor in global average temperature. My question is why is CO2 touted as the major catalyst in climate change science? Is it because it's the thing we have the most control over? Or is it measurably the thing that has changed the most (so scientists assume it's the major catalyst?). Are there other factors that haven't been researched as much as CO2 that could possibly play into the global average temperature or is CO2 definitely it?
I haven't done too much research in the field myself so forgive my ignorance. I think it would help if you outlined the major contributors to global temperature average. I have heard a lot about water vapor dwarfing CO2 as a mitigating factor in global average temperature. My question is why is CO2 touted as the major catalyst in climate change science? Is it because it's the thing we have the most control over? Or is it measurably the thing that has changed the most (so scientists assume it's the major catalyst?). Are there other factors that haven't been researched as much as CO2 that could possibly play into the global average temperature or is CO2 definitely it?
very cool question, were deep in the science now.
water vapor is a very strong greenhouse gas, much stronger in overall effect than co2 because there is much more water vapor in the atmosphere then co2. co2 is much more efficient in the sense of warming / concentration, though.
but the main argument is again the equilibrium: lets go for a thought experiment:
imagine earth at a certain equilibriumg with a given water vapor and co2 concentration. increase co2 a little bit, it gets a little bit warmer. warmer means more water vapor (http://en.wikipedia.org/wiki/Clausius%E2%80%93Clapeyron_relation , real physics, yeah °), means a strengthening of the original co2 signal to a new equilibrium.
it is supposed that for a medium emission social scenario we would have perhaps 1 degrees of warming ONLY due to co2 increase. water vapor would add another 1 degree on that just in reaction (we can control water vapor ONLY via temperature). the rest of the uncertainty comes from the reaction of clouds.
hope that helps, if not, please ask again
On December 13 2011 08:41 Knalldi wrote:
The thing with the water is more complicated as far as i know, as it even depends on the daytime if Watervapor is cooling or heating. Cloudy night -> warmer Cloudy day -> colder. Isnt it really hard to factor all this in..? i dont like the one way approach of only warming water vapour.
The thing with the water is more complicated as far as i know, as it even depends on the daytime if Watervapor is cooling or heating. Cloudy night -> warmer Cloudy day -> colder. Isnt it really hard to factor all this in..? i dont like the one way approach of only warming water vapour.
it is a simplification in the following sense:
a model with increased co2 and fixed water vapor will warm x degrees.
a model with increased co2 and variable water vapor that changes with warming will warm x+ y degrees.
this means that the overall effect of water vapor is y degrees, even if local / temporal effects are more complicated . and they are also represented in the models all the time! btw: clouds != water vapor feedback.
On December 13 2011 08:45 mAgixWTF wrote:
Is it true that manymanymany years ago, when there was a LOT more CO2 in the air, Africa was a green continent? I saw a german documentary once about this, and there they said the temperature was higher, but Africa was green.
Is it true that manymanymany years ago, when there was a LOT more CO2 in the air, Africa was a green continent? I saw a german documentary once about this, and there they said the temperature was higher, but Africa was green.
its called the green sahara hypothesis for about 9k-6k before present for a earth with different orbital configuration that lead to different climate in different parts. its a different perturbation than the well-mixed co2 gas.
however, even this hypothesis is nowadays under attack. the simulations and paleo records that lead to this hypothesis were simple / spares. more modern data and more complex models show that likely the change of precipiation events was higher, which lead to the records of plants in the sahara. it is unlikely that the full sahara was green, as sweet as this hypothesis was anyway
On December 13 2011 08:56 besteady wrote:
@dabbeljuh I hope this hasnt come up already, but do you think that we are currently seeing the effects of climate change at present? I heard an example story in the news about how it is possible that a herder in Africa may have to take his herd to a further away watering pool because the closer one has dried up, this new watering hole is also in an enemy tribes territory and if he is murdered it could be argued that it is the result climate change.
I've also read that the US military is already preparing for the results of climate change, while what seems like the whole of the Republican party is still in denial. Do you feel like the leaders simply do not care about what might be the result of global warming, or do you think they are ignorant enough to not believe the evidence.
@dabbeljuh I hope this hasnt come up already, but do you think that we are currently seeing the effects of climate change at present? I heard an example story in the news about how it is possible that a herder in Africa may have to take his herd to a further away watering pool because the closer one has dried up, this new watering hole is also in an enemy tribes territory and if he is murdered it could be argued that it is the result climate change.
I've also read that the US military is already preparing for the results of climate change, while what seems like the whole of the Republican party is still in denial. Do you feel like the leaders simply do not care about what might be the result of global warming, or do you think they are ignorant enough to not believe the evidence.
a) I heard the argument that Darfur was the first war. This has been proposed by sociologists with close connections to physical climate science, I will not contradict their findings. I am not 100% convinced, though, that you can do a strict "Detection & Attribution" (D&A) method for this type of problems. D&A is one scientific way to look at a problem, see if it is unsual (detection) and try to rule out all possible explanations but one (attribution). I think this is reasonably hard for war situations.
It is clear, however, that many conflicts in todays world depend heavily on ecosystems and water as a climate related product. These problems might increase in the future
b) The German military also has such preparation reports. Mostly this concerns the defense against climate fugitives ... a scary thought, building a wall across the European / African Border
On December 13 2011 09:09 LennyLeonard wrote:
I Think i just gg'ed global warming. Its the fucking sun people. Look at who is funding the research that promotes the global warming theory. Al Gore for instance, funds many a research project, and is also involved in making millions off of carbon credits and the like. If you don't believe me, watch this video which proves 100% that what i am saying is true.
I Think i just gg'ed global warming. Its the fucking sun people. Look at who is funding the research that promotes the global warming theory. Al Gore for instance, funds many a research project, and is also involved in making millions off of carbon credits and the like. If you don't believe me, watch this video which proves 100% that what i am saying is true.
I am sorry but game is not over °J° You say: its the sun!
That is the most used and most contradicted denialist argument of the last decades. I dont know where you got your reconstruction from but I would refer you to the new Berkely independent study funded by climate sceptics that will contradict your plot.
Additionally, please read here for follow-up information:
http://www.skepticalscience.com/solar-activity-sunspots-global-warming.htm
Simple answer:
In the last 35 years of global warming, sun and climate have been going in opposite directions
btw: there are parts of the its the sun hypothesis that are interesting, as the connection of cosmic rays and cloud formation. they are discussed in the scientific community and have been shown - so far - to be wrong.
On December 13 2011 09:03 Sm3agol wrote:
Here is my most burning question, as a pretty ignorant "denier" in the sense that I don't believe it's quite as big of an issue as it's made out to be ......why the sudden spike? We are going along all fine and dandy in the 1800's..... early-ish1900s, burning so much coal, and just blowing the smoke directly back into the atmosphere, that places like London never actually see the sun for months on end. Cars are invented and noone gave a crap about emissions for 60 years..... just blew that crap right back into the air. People are warning about global cooling in the 60's for crying aloud. So we start getting more environmentally conscious, and start emissions laws, start caring about pollution, and suddenly, NOW(1990s and on), when we start actually having emissions restrictions, pollution is a big deal, etc, the temperature is "rising like never before", and we have this big hullaballoo about everyone dying to rising sea water in 50 years. Makes no sense to me......other than maybe it's all China/Indias fault... but I doubt it. Just the whole thing stinks of a small scientific issue/anomally, possibly and probably slightly exacerbated by human pollution, that politicians and money hungry porkers latched on to to launch their name into the spotlight and fund their own private cash cows.
Here is my most burning question, as a pretty ignorant "denier" in the sense that I don't believe it's quite as big of an issue as it's made out to be ......why the sudden spike? We are going along all fine and dandy in the 1800's..... early-ish1900s, burning so much coal, and just blowing the smoke directly back into the atmosphere, that places like London never actually see the sun for months on end. Cars are invented and noone gave a crap about emissions for 60 years..... just blew that crap right back into the air. People are warning about global cooling in the 60's for crying aloud. So we start getting more environmentally conscious, and start emissions laws, start caring about pollution, and suddenly, NOW(1990s and on), when we start actually having emissions restrictions, pollution is a big deal, etc, the temperature is "rising like never before", and we have this big hullaballoo about everyone dying to rising sea water in 50 years. Makes no sense to me......other than maybe it's all China/Indias fault... but I doubt it. Just the whole thing stinks of a small scientific issue/anomally, possibly and probably slightly exacerbated by human pollution, that politicians and money hungry porkers latched on to to launch their name into the spotlight and fund their own private cash cows.
good questions, complex question.
one part: the drivers:
a) think population increase. we have now 7 billion people on earth, 1800 it was 1, 1900 less then 2. emission is proportional to population.
b) think technology increase. we have much more ways nowadays to spend energy,
c) think wealth increase. we have much more middle class people, potentially more than we have humans back in 1900.
second part: aerosols
there is a hypothesis that the aerosols (i.e. air pollution) damped the warming. I am not quite convinced that this is true but it is current scientific consensus.
third part: internal variability
there is variability in the earth#s ocean that can lead to changes on the 30-60 year time scale that is SUPERPOSED on the global warming trend.
fourth part: latency.
more co2 -> more heat is trapped -> goes into upper ocean until mixed layer is warmed, this takes decades! -> after that the atmosphere starts warming more.
the full effect is a combination of that and not yet fully understood, you could make a career out of solving this
On December 13 2011 09:22 slytown wrote:
"by burning carbon that has been accumulated over many millions of years and been stored in fossil fuels. the earth#s carbon cycle is in a fragile equilibrium, by releasing energy in an incredible fast manner, we do impact climate in an unprecedented speed. hope that helps!"
OK, I am skeptic only because I have heard the explanations and anthropological carbon-dioxide from what I understand is not a contributor to the global warming context but could (in theory) have a cooling effect globally. So, according to "skeptics" like Patrick Moore, Richard Lindzen, and Bob Carter, the "hockey stick" theory is bunk becauase it neglects the effect temperature has on CO2 levels, not the other way around. Also, and the more important point, the recent rise in global temperature is a result of two effects: water vapor's reflection of solar rays and the sun's solar activity cycles.
Do you agree with these effects or is CO2 still the culprit?
"by burning carbon that has been accumulated over many millions of years and been stored in fossil fuels. the earth#s carbon cycle is in a fragile equilibrium, by releasing energy in an incredible fast manner, we do impact climate in an unprecedented speed. hope that helps!"
OK, I am skeptic only because I have heard the explanations and anthropological carbon-dioxide from what I understand is not a contributor to the global warming context but could (in theory) have a cooling effect globally. So, according to "skeptics" like Patrick Moore, Richard Lindzen, and Bob Carter, the "hockey stick" theory is bunk becauase it neglects the effect temperature has on CO2 levels, not the other way around. Also, and the more important point, the recent rise in global temperature is a result of two effects: water vapor's reflection of solar rays and the sun's solar activity cycles.
Do you agree with these effects or is CO2 still the culprit?
It is proven beyond doubt that increasing Co2 concentration will increase temperature.
It is also proven beyond doubt that a warmer Earth has a warmer ocean that can carry less (!) CO2.
So, thought experiment:
Orbital changes induce temperature change -> warmer Earth -> warmer ocean -> emission of CO2 -> even warmer Earth.
This has happened in the past and explains that in these plots in some periods, CO2 leads temperature.
This does not invalidate the current problem:
Human induced CO2 change -> warmer Earth -> warmer ocean -> emission of CO2 -> even warmer Earth.
Concerning your
"
the recent rise in global temperature is a result of two effects: water vapor's reflection of solar rays and the sun's solar activity cycles"
What you mean is the argument that solar rays excite cloud formation and that sun activity influences global SAT. Direct measurementas (satellite) show however, that global temperature and sun activity are NOT correlated, they point in different directions even for the last 35 years. I refer you to http://www.skepticalscience.com/solar-activity-sunspots-global-warming.htm for more infos.
On December 13 2011 09:37 slytown wrote:
Graphs don't scare me. Where is the evidence that CO2 is the culprit? That's the issue here with the "global warming scare." I'm not saying I'm an idealogue, but i want DIRECT CORRELATION between every rise in temperature of recent with CO2 levels. A bigger question is is that even possible?
Sorry, I'm no a climate scientist so I am unfamiliar with all the terminology. Great thread by the way dabbelijuh.
Graphs don't scare me. Where is the evidence that CO2 is the culprit? That's the issue here with the "global warming scare." I'm not saying I'm an idealogue, but i want DIRECT CORRELATION between every rise in temperature of recent with CO2 levels. A bigger question is is that even possible?
Sorry, I'm no a climate scientist so I am unfamiliar with all the terminology. Great thread by the way dabbelijuh.
it is not possible to show this direct correlation for single anomalies, only for the global trend..
think of a pot of water on a cooker: you will not be able to correlate the bubbles in the water with small fluctuations of the cooker itself. you will be reasonably sure, though, that the warming of the water is due to the cooker.
now think of earth as that pot but + many strange effects that shake the pot, put ice in it, activate the cooker irregularly, lift and drop the pot from time to time.
the result will be a chaotic evolution wheren you _CANNOT_ directly correlate cooker and pot temperature, but the causal effect is still there.
I would much appreciate if things would be easier (and beware of people who it is, it is not. Earth is one of the most complex systems mankind has ever tried to describe. ).
And please, ignore the graph, look at my thought experiment
EDIT: and no reason to excuse yourself because your not a climate scientist, sometimes I wish I wouldnt be one
On December 13 2011 09:29 Hundisilm wrote:
I've been puzzled a bit why loss of ice caps is considered to be a positive feedback. Sure the albedo of ice is pretty neat, but the poles aren't probably the sunniest places on the earth and snow on ice should be a quite nice insulator (as we can see the rather low number of degrees over there). Along with the Gulf Stream I would expect the loss of polar ice hat to have a nice cooling effect on earth. I would assume that climate peoples have done some calculations on them at some point or another (I'm assuming it is considered to be less than the albedo difference), but I haven't ran into anything on this subject so far (negative feedback of loss of snow/ice cover).
I've been puzzled a bit why loss of ice caps is considered to be a positive feedback. Sure the albedo of ice is pretty neat, but the poles aren't probably the sunniest places on the earth and snow on ice should be a quite nice insulator (as we can see the rather low number of degrees over there). Along with the Gulf Stream I would expect the loss of polar ice hat to have a nice cooling effect on earth. I would assume that climate peoples have done some calculations on them at some point or another (I'm assuming it is considered to be less than the albedo difference), but I haven't ran into anything on this subject so far (negative feedback of loss of snow/ice cover).
very good point.
people thought a long time that the loss of summer ice would be a strong positive effect
(warmer earth -> less ice -> more water -> more sunshine absorption -> warmer water -> less ice and so forth).
this is true! but once the summer ice is melted and the water is really cosily warm, winter will come. the water will then rapidly cool, lead to a local temperature anomaly and build up ice again, which will very fast again insulate the ocean vs the very cold winter atmosphere.
in the end, the summer ice positive feedback is existent, but not as strong as people argued ten years ago because in winter it will very rapidly get back to normal.
On December 14 2011 06:14 henkel wrote:
love this debate topic. I personally do believe man kind as a whole can affect global climate, That we are changing it and that is a bad thing that has to be slowed down as much as possible. I don't think it can be stopped
Second of year of my Biology bachelor we had a graded debate about it, I argued against, on the topic of man made global climate change. There were no specialist present so maybe you can address these points that weren't disputed properly there. Doing this of out of memory, so might be a bit hit and mis.
if man made global climate change is a fact why was there the "climate-gate" scandal?
Wasn't the IPCC's report that started it all, especially Michal Mann's graph, based on wrongly executed statistics and non-random measuring points specifically chosen to proof his hypothesis.
Isn't the climate and it's feedback systems to poorly understood to be able to make any reliable predictions on the future climate. For example water temperature rising -> less Co2 absorption by water but on the other hand higher water temperature -> more algae -> more Co2 absorption.
These are the ones i can remember, should look in my old notes.
would like to ad though that u made a dam nice OP.
love this debate topic. I personally do believe man kind as a whole can affect global climate, That we are changing it and that is a bad thing that has to be slowed down as much as possible. I don't think it can be stopped
Second of year of my Biology bachelor we had a graded debate about it, I argued against, on the topic of man made global climate change. There were no specialist present so maybe you can address these points that weren't disputed properly there. Doing this of out of memory, so might be a bit hit and mis.
if man made global climate change is a fact why was there the "climate-gate" scandal?
Wasn't the IPCC's report that started it all, especially Michal Mann's graph, based on wrongly executed statistics and non-random measuring points specifically chosen to proof his hypothesis.
Isn't the climate and it's feedback systems to poorly understood to be able to make any reliable predictions on the future climate. For example water temperature rising -> less Co2 absorption by water but on the other hand higher water temperature -> more algae -> more Co2 absorption.
These are the ones i can remember, should look in my old notes.
would like to ad though that u made a dam nice OP.
hi henkel,
1) climategate: climate science is a big science with thousands of people around the world doing their research. there are big egos (too many °), some rightly so, some not so much. some are editors of certain magazines and push their own position more than it is perhaps correct in a perfect world. this does not mean, that there is some strange censorship going on, it just means that scientists are human. each IPCC AR (all four) are the work of hundreds of individuals in their spare time, nobody gets paid for anything. then, some people STEAL emails, a few hundred thousand and search them to quote out of context. they find nothing except some rude language and a few people not behaving perfectly °J° that is climategate for me. if someone would publish all EXXON emails of the last ten years and would search for bad language, do you think they would find something?
2) it was the third assessment report (TAR) with the hockeystick graph put very prominently into the summary for policy maker. there were some minor statistical irregularities in the original method, those have been shown in the literature and have been remedied. the resulting graph looks close to identical. even if the full graph would be wrong, the other 1000 pages of evidence would not be invalidated. the hockeystick is NOT essential for climate science, whatsoever. it is just one reconstruction for the northern hemisphere and it was used quite a lot to convince politicians. it was a means of communication, not a major scientific breakthrough in itself.
3) climate feedbacks and their respective strengths is indead current research topic, resulting in uncertainty of the climate response to certain forcing changes. it is current understanding however, that this uncertainty is smaller than the signal itself.
hope that helps!
w
On December 14 2011 05:53 kinkulaattori wrote:
I would have a question not directly about yes or no climate change, but would like to ask your oppinion on CCS (for those who don't know =carbon capture and storage). In my oppinion somehow it sounds pretty stupid that the people who yesterday cried about nuclearpower storing it's waste in the mountain now propose themselves to store their waste (co2) in the very same place, and even call it the "solution" to global warming. I find that rather stupid tbh.
I would have a question not directly about yes or no climate change, but would like to ask your oppinion on CCS (for those who don't know =carbon capture and storage). In my oppinion somehow it sounds pretty stupid that the people who yesterday cried about nuclearpower storing it's waste in the mountain now propose themselves to store their waste (co2) in the very same place, and even call it the "solution" to global warming. I find that rather stupid tbh.
hi kinkulaattori,
here is my opinion (based on general knowledge of the field, no specific expertship in this area).
a) co2, even if it would come back to the earth is not so toxic as nuclearwaste; it would probably be dangerous for only very few people close to the site, and then it would go back up into the atmosphere (remember, CO" is a well mixed gas).
b) It will not be a solution because it will diffuse back to the atmosphere in the end, it is just a question when. CSC - if it works - would just buy humanity a few decades of understanding the science better and getting the technology needed for a renewable only energy supply.
I believe CSC is at the moment just one exploratory technology, not the solution it is made to be.
On December 14 2011 04:39 storm8ring3r wrote:
What is the incentive for a climate scientist to predict that everything is going to be okay
What is the incentive for a climate scientist to predict that everything is going to be okay
I am a physicist working as a climate scientist. If I could find a serious flaw in all climate models and all data measurements and all climate reconstructions and all simple energy budget models (big if), I would be the most well know scientist on Earth, I assure you of that. I would come up with a new theory of decadal changes and would put up the best research programme on earth to understand that new prediction system. OR I would just go into consulting °J°
-> bottom line: scientists are funded permanently (very few, they dont really care what they find out, they are safe) or in projects that run 1-3 years (big majority). this wouldnt change if climate change is not so drastic. over time the amount of money spend into scientifically boring projection exerciseswould spread back to understanding the complex Earth system. I would be happy about that, that would be the incentive, more real science, less politic exposure.
On December 14 2011 05:28 liberal wrote:
Actually, it will be a waste of time either way. In fact, even if we were able to convince every single person that ever visits this thread that man-made global warming is real, it would still be a waste of time because there truly isn't a legitimate solution to the problem yet. So long as population increases, so long as more nations industrialize, so long as we don't have a severe global economic depression, CO2 emissions worldwide will simply continue to increase. The real denial is believing government can do anything to stop it.
Actually, it will be a waste of time either way. In fact, even if we were able to convince every single person that ever visits this thread that man-made global warming is real, it would still be a waste of time because there truly isn't a legitimate solution to the problem yet. So long as population increases, so long as more nations industrialize, so long as we don't have a severe global economic depression, CO2 emissions worldwide will simply continue to increase. The real denial is believing government can do anything to stop it.
Hi Liberal,
I will take your post as one representative of all the "it just doesnt matter" posts
It is not true. Climate Change is a global challenge, and we have to try to prevent the powers that be of manipulating us. IF you guys, as educated young people in rich countries dont believe that climate change is happening, there is no change in hell that the governments of 2020 or 2030 will be more rational than now.
It is a fair point to say, you do not see the politicl system to react in time, I partially agree.
I still believe it is our responsibilty to talk about this. We are changing EArth in many ways, Climate Change is one of them. Most are not sustainable. Most of them are bad for us and those that follow us. If humanity wants to claim to be sentient in a global sense, at one point we HAVE to change strategy. This can be government guided, could be consumer based, could be a big ethical swingback, who knows. I just think, everybody should get their facts straight.
I repeat something from my OP: the reaction of society is not the responsibility of science, it is your responsibility, our responsibility as citizens.
In my opinion as citizen: do we like the way Earth is operated right now, in our western, liberal, rich countries?
Cheers,
W
On December 14 2011 01:35 ELA wrote:
@OP:
Im not a denialist by any means, its pretty obvious that climate changes are happening. However, I do believe that the amount of funds that we currently use to reduce emissions is way way too high, compared to what we spend on solving other problems (Koyoto countries = ~1% of BNP for all of them, some more, some less every year). Would it not be benificial to spend way more money on research in green technology (Wind power, Solar panels, particle filters etc) instead of spending insane amounts of money on the inefficient and very costly practical solutions we have available today? The funds that every year goes into complying with the Koyoto agreement, could solve world hunger and provide basic education for every child on the planet (Lomborg), while the Koyoto agreement it self dosn't have a very big impact on the climate.
Basicly: We could do alot more good with the money that we are currently spending on applying inefficient solutions to the complicated problem that is global warming. Spend more money on research in the field, and spend the rest of the money on problems that we actually know how to fix right now (Hunger, sanitation, diseases, education) - The cost would be about the same.
I would like to know your thoughts
@OP:
Im not a denialist by any means, its pretty obvious that climate changes are happening. However, I do believe that the amount of funds that we currently use to reduce emissions is way way too high, compared to what we spend on solving other problems (Koyoto countries = ~1% of BNP for all of them, some more, some less every year). Would it not be benificial to spend way more money on research in green technology (Wind power, Solar panels, particle filters etc) instead of spending insane amounts of money on the inefficient and very costly practical solutions we have available today? The funds that every year goes into complying with the Koyoto agreement, could solve world hunger and provide basic education for every child on the planet (Lomborg), while the Koyoto agreement it self dosn't have a very big impact on the climate.
Basicly: We could do alot more good with the money that we are currently spending on applying inefficient solutions to the complicated problem that is global warming. Spend more money on research in the field, and spend the rest of the money on problems that we actually know how to fix right now (Hunger, sanitation, diseases, education) - The cost would be about the same.
I would like to know your thoughts
hi ela,
while there are big difficulties to distinguish which generation should take the burden of paying for climate change adaptaton or mitigation (because those generations before us wont °), I would not simply believe Lomborg but look also in reports like the Stern report. Some parts of the money that go into the Kyoto protocol
, namely into the Clean Development MEchanism (the method to spend money in developing countires to save emissions in rich countries), go into things like poverty control, or have at least one part in this, so I see that this "Green" money is also trying to accomodate social questions (see gold label http://www.cdmgoldstandard.org/)
Still, I believe it is clear, that equity, hunger, poverty and climate change adaptation / mitigation are intrinsically linked. I suggest you have a look at the Working Groups II and III of the IPCC to find more information on that, I am not an expert, so I cannot link you to more specific literature.
One last thing: the Kyoto Protocol is a political result, so th emoney countries spend for it is mostly in their own interest for things they would do anyway. Now, with Canada, its the first time they would have to pay money to others - and they leave it. This shows a big problem of international climate diplomacy.
On December 14 2011 01:41 archonOOid wrote:
OP, at which point in time or at what levels of CO2 will ( or need to) man kind start to implement geoengineering to curb the effects of climate change trough different kinds machines (carbondixoid traps) or increasing the sulphurdixoid levels.
OP, at which point in time or at what levels of CO2 will ( or need to) man kind start to implement geoengineering to curb the effects of climate change trough different kinds machines (carbondixoid traps) or increasing the sulphurdixoid levels.
If I could answer that question, I would be very rich. I fear that the idea that we will find simple technological methods that remedy the bad effect of CO2 is too simpleminded, because as people have pointed out, single countries or regions will be profiting from climate change, and some might explicitly suffer from such global geoenieering methods. I sincerely doubt that we have a robust enough international policy regime to guide and manage such methods.
It might happen, however, that some countries that will suffer under extreme climate change related problems, will do this on their own. If this happens, than lets just hope that we will have a fallback plan °J°
On December 14 2011 02:23 Exoteric wrote:
I remember reading some remarks from climate change scientists that it will happen regardless of human intervention, it's just that we're accelerating the process. With that in mind, to what degree are we accelerating it in comparison with a natural change and what sort of government response would be necessary for there to be a noticeable positive impact overall? Some figures would put this into perspective for me. It's hard to break away from the apathetic attitude most people have (me included) towards global warming. I mean, I have solar panels for my household, energy saving light bulbs and whatnot, but I don't really think I'm making any kind of practical difference overall and it's more of a feel-good thing.
I remember reading some remarks from climate change scientists that it will happen regardless of human intervention, it's just that we're accelerating the process. With that in mind, to what degree are we accelerating it in comparison with a natural change and what sort of government response would be necessary for there to be a noticeable positive impact overall? Some figures would put this into perspective for me. It's hard to break away from the apathetic attitude most people have (me included) towards global warming. I mean, I have solar panels for my household, energy saving light bulbs and whatnot, but I don't really think I'm making any kind of practical difference overall and it's more of a feel-good thing.
hi exoteric,
thanks for your comments.
I dont think your statement is correct per se, we do not know of any other mechanism that could have initiated the 20th centruy warming. One thing that might play into your perception is the hypothesis, that Earth will warm even if we curb emissions right now. This is true, it has to do with the inertia of the system, especially the ocean. sorry, I dont really have a figure for that.
The problem with the lack of "actionable" science is a very valid one. I see it for myself: I dont have a car, use public transportation, use renewable energy, eat less meat (but cant go around a good burger), try to behave nicely and still my CO2 footprint is immense just from not freezing in winter. Its tough.
I believe we should act responsible personally, vote for responsible parties and try to identify companies that try to tackle the problem and help them.
The solution will only be sustainable if government, private individuals and companies work hand in hand, so to speak.
One thing btw is the possibility of compensating flights (I know it will be expensive for you down under
here is a german organisation who spends money to offset your flights by investing in green energy projects in developing countries, supported are only CDM measures with gold label
https://www.atmosfair.de/en/home/
hi ipunatic, good question.
the question of overfitting / tuning / free parameters is a scientific grand challenge for climate models. it is simply not possible to test all reasonable paramater combinations due to the fact, that coupled ocean - atmosphere models have to be run thousands (!) of model years to achieve equilibrium, which is incredibly expensive on modern high performance computer.
so the answer is: yes, there are elements that are adjusted by hand, or by expert judgement. there is however a whole science evolving around the idea of a perturbed physics parameter ensemble (where I am also currently active), that tries to put a mathematical framework around the concept of tuning.
one thing you should keep in mind is the fact, that those perturbed physics ensembles usually have quite a similar behavior as ensembles of opportunity as the IPCC ensemble, which is essentially a mix of randomly produced climate models around the world.
if you do bayesian analysis with these type of ensembles, both ensembles will in the end lead to the same - as of now structural - uncertainty range in climate sensitivity.
these adjustments are btw done in something called "control run", a thousand year equilibrium run with forcing of 1880 or so, pre-industrial. all experiments later on (historical, projections,...) are then done with this set of parameters, so at least it is possible to evaluate this specific model version against observations in a weak sense.
On December 15 2011 10:04 Capook wrote:
How about this one, from a genuine "skeptic" (yours truly). I'm only "skeptical" about some aspects of the science--my main gripe is with the policies advocated by most climate change people.
It's clear that the earth is warming, and from basic physics it seems likely that co2 is the cause. But that's not too interesting for policy. What matters is how much the warming will continue (say, global mean temperature in 2050), and what the environmental consequences will be. To answer these questions requires simulating the entire earth, which is basically impossible. The current models contain hundreds of fudge factors that must be fit to past data. They all do it in different ways, and their predictions diverge rapidly. Also, the predictions of a single model often changes wildly (well outside the statistical error bars of the previous model) when new physics is added. This is because--as everybody knows--the overwhelming source of error is systematic, in that the included physics is not correctly modeled and much physics known to be relevant is not included. In no other field of science (certainly not mine) would the quantitative results of such simulations be taken seriously, and yet in climate science policy documents you see statistical error bars slapped on results of whatever the latest simulations are (with some averaging over different models), and pedaled as scientific predictions to world leaders.
Here's what I would want to see before quantitative simulation results can be considered reliable. For each model, train on only 1/2 the available data, and then verify that the remaining half is reproduced before making predictions. Verify that all secondary aspects are reproduced as well (such as measured ice melt rates, etc.). For each code, verify that each time new physics is introduced, the results remain consistent with previous results. And across all codes, make sure that agreement remains within statistical error bars for each code. I have seen two climate simulation presentations made for physicists, and none of them showed any of this. I have also directly asked some experts and none could produce such tests. I therefore assume that these criteria are (roundly) not satisfied. In that case the simulations can be regarded as providing further evidence for the hypothesis that co2 caused and will continue to cause warning, but can not be used to infer anything quantitative about the future.
The bottom line is we know next to nothing about what the scope and impact of global warming will be. This should be straightforwardly communicated to policymakers so they can make the best decisions. In my own personal opinion, it makes no sense to spend tons of money on combating co2 emissions based on the idea that (e.g.) droughts and floods *might* cause food shortages for people in 50 years, when these same people *are* facing food shortages and many other problems right now. If we spent a tenth of what is proposed to be spent to combat global warming on current problems in the third world, it would be truly a testament to the charity and generosity of western liberalism and environmentalism. On a final personal note, I count myself both a liberal and an environmentalist, but not a gambler. Since the impact of co2 emissions is so incredibly uncertain and there are so many certain problems now, let's spend our limited money, time, and energy fixing the certain ones.
How about this one, from a genuine "skeptic" (yours truly). I'm only "skeptical" about some aspects of the science--my main gripe is with the policies advocated by most climate change people.
It's clear that the earth is warming, and from basic physics it seems likely that co2 is the cause. But that's not too interesting for policy. What matters is how much the warming will continue (say, global mean temperature in 2050), and what the environmental consequences will be. To answer these questions requires simulating the entire earth, which is basically impossible. The current models contain hundreds of fudge factors that must be fit to past data. They all do it in different ways, and their predictions diverge rapidly. Also, the predictions of a single model often changes wildly (well outside the statistical error bars of the previous model) when new physics is added. This is because--as everybody knows--the overwhelming source of error is systematic, in that the included physics is not correctly modeled and much physics known to be relevant is not included. In no other field of science (certainly not mine) would the quantitative results of such simulations be taken seriously, and yet in climate science policy documents you see statistical error bars slapped on results of whatever the latest simulations are (with some averaging over different models), and pedaled as scientific predictions to world leaders.
Here's what I would want to see before quantitative simulation results can be considered reliable. For each model, train on only 1/2 the available data, and then verify that the remaining half is reproduced before making predictions. Verify that all secondary aspects are reproduced as well (such as measured ice melt rates, etc.). For each code, verify that each time new physics is introduced, the results remain consistent with previous results. And across all codes, make sure that agreement remains within statistical error bars for each code. I have seen two climate simulation presentations made for physicists, and none of them showed any of this. I have also directly asked some experts and none could produce such tests. I therefore assume that these criteria are (roundly) not satisfied. In that case the simulations can be regarded as providing further evidence for the hypothesis that co2 caused and will continue to cause warning, but can not be used to infer anything quantitative about the future.
The bottom line is we know next to nothing about what the scope and impact of global warming will be. This should be straightforwardly communicated to policymakers so they can make the best decisions. In my own personal opinion, it makes no sense to spend tons of money on combating co2 emissions based on the idea that (e.g.) droughts and floods *might* cause food shortages for people in 50 years, when these same people *are* facing food shortages and many other problems right now. If we spent a tenth of what is proposed to be spent to combat global warming on current problems in the third world, it would be truly a testament to the charity and generosity of western liberalism and environmentalism. On a final personal note, I count myself both a liberal and an environmentalist, but not a gambler. Since the impact of co2 emissions is so incredibly uncertain and there are so many certain problems now, let's spend our limited money, time, and energy fixing the certain ones.
hi capook,
awesome post. the methodology you suggest is not complex in itself and evident to all students of machine learning or related topics. I was baffled myself that it was not used consistently in climate research so far.
the reasons are clear: global circulation models did not start as prediction models but as tools to understand processes and to complement data.
now, they are used to make projections of some type, and the focus is clearly on the more hard evaluation tests you suggest. I know that the section on model evaluation of the forthcoming IPCC report AR5 will be much more clear on this part, that so far the evaluation procedure lacks scientific rigour in some parts.
Still, your argument "we know next to nothing about what the scope and impact of global warming will be" is plain wrong. Even with very simple, one line energy budget models you can estimate global warming of certain magnitude. The radiative transfer models that can estimate warming for a single air column due to enhanced CO@ concentration are "parameter free" in the sense that they are just numerical approximation of well know physical equations. They do predict a warming of around 1 degree centrigrade per doubling of CO2. There is close to non euncertainty in this number.
As I mentioned earlier in this thread, the feedbacks that enhance this direct effect are the cause of uncertainty, i.e. clouds, water vapor, vegetation change, ice cover change, x.. This adds up to the current understanding of around 3-5 degrees warming per doubling of CO2, which is also consistent with DATA (20th century) and RECONSTRUCTIONS (paleo time periods).
Bottom line: while there is room to improve evaluation of climate models and it is currently done, see tendency to falsifiable decadal predictions, the result does not mean, we know nothing of climate change. It just indicates again, that the problem is complex.
On December 20 2011 22:58 TanGeng wrote:
Great stuff. I'd settle for making the code for models publicly available. Only then can the model results be reproducible and interested individuals can attempt to run the models themselves. Otherwise, the model creators only give the rest of us a choice between trust and distrust.
The verification steps that you are suggesting are diagnostics. They are used to convince oneself and anyone who has access to the code and its diagnostic tests of the accuracy of the models. If the model creators have not run those tests themselves, it's very hard to believe that they should have any confidence in their own model's projections.
As an additional comment, the use of 1/2 of the available data to predict the remaining half is very ambitious. It'd require foreknowledge of unpredicted forcings like volcano eruptions, solar variations, and CO2 concentrations. It'd be enough to examine the sensitivity of the model parameters to the data by training it to different time periods. If the parameters are highly sensitive and fluctuate wildly, then the modelers haven't achieved stability in model parameters.
Great stuff. I'd settle for making the code for models publicly available. Only then can the model results be reproducible and interested individuals can attempt to run the models themselves. Otherwise, the model creators only give the rest of us a choice between trust and distrust.
The verification steps that you are suggesting are diagnostics. They are used to convince oneself and anyone who has access to the code and its diagnostic tests of the accuracy of the models. If the model creators have not run those tests themselves, it's very hard to believe that they should have any confidence in their own model's projections.
As an additional comment, the use of 1/2 of the available data to predict the remaining half is very ambitious. It'd require foreknowledge of unpredicted forcings like volcano eruptions, solar variations, and CO2 concentrations. It'd be enough to examine the sensitivity of the model parameters to the data by training it to different time periods. If the parameters are highly sensitive and fluctuate wildly, then the modelers haven't achieved stability in model parameters.
just concerning the code thing: most models are available for free, see for example MIT GCM http://mitgcm.org/ (if you write an email to the team that holds true for most models, they are usually on a repository and changed daily, and therefore not just available in the net), they can still probably not easily be used by interested individuals due to the lack of high performance computing facilities for that interested individual.
I was part of a big model development effort, and it takes 3 hours to compile the most current version of the model on a 8000 processor super computer, and literally months to run it for a significant time. It takes new PhD students and scientists weeks to months to be able to run these models, so it is _not_ just a question of model availability.
Additionally, data is free! See for example hadcrut temperature time series raw date (at the bottom of http://www.cru.uea.ac.uk/cru/data/temperature/ ). Most model output is freely available, if you google CMIP3 and CMIP% data you will get access to all data from the current run of the models. Model documentation is free. (see for example MIT general circulation model again http://mitgcm.org/; I am not from MIT, just mentioning it because it is very well documented)
hope that helps,
w
On February 06 2012 07:19 Dbla08 wrote:
climate change is undeniable, its happening. but "global warming" was the biggest fucking farce in human history, al gore made billions off scaring people with an illogical 5th grade level powerpoint presentation.
Edit: also, if anyone truly believes that carbon-dioxide is the sole cause of climate change, they've either been horribly fooled or are horribly stupid. methane is almost 10x more dense than carbon dioxide, and its prevalence is growing much more rapidly than carbon dioxide. the industrial slaughter of cows/pigs etc, as well as the frozen tundra of russia releasing large quantities of methane contribute to climate change so much more than the carbon dioxide the biomass of earth produces, and consumes, the eco-system has a natural way of eliminating massive amounts of carbon dioxide. its called photosynthesis via chlorophyll, and every plant that's green does it. methane doesn't have such an out, it simply stays or is burned and broken down into CO/CO2 and some other trace chemicals etc.
climate change is undeniable, its happening. but "global warming" was the biggest fucking farce in human history, al gore made billions off scaring people with an illogical 5th grade level powerpoint presentation.
Edit: also, if anyone truly believes that carbon-dioxide is the sole cause of climate change, they've either been horribly fooled or are horribly stupid. methane is almost 10x more dense than carbon dioxide, and its prevalence is growing much more rapidly than carbon dioxide. the industrial slaughter of cows/pigs etc, as well as the frozen tundra of russia releasing large quantities of methane contribute to climate change so much more than the carbon dioxide the biomass of earth produces, and consumes, the eco-system has a natural way of eliminating massive amounts of carbon dioxide. its called photosynthesis via chlorophyll, and every plant that's green does it. methane doesn't have such an out, it simply stays or is burned and broken down into CO/CO2 and some other trace chemicals etc.
Hi Dbla08,
I still believe that Global Warming is an appropriate term for one major consequence of anthropogenic induced climate change, i.e. an expected increase in global surface air temperature for the case of continued increase in atmospheric carbon dioxide levels.
Concerning your argument wrt Co2:
a)here is an interesting video concerning the evolution of CO2
http://www.esrl.noaa.gov/gmd/ccgg/trends/history.html
It shows that the yearly cycle in CO2 production and assimilation that is synchronized with (northern hemisphere) vegetation is very strong, but that you can also very easily - by eye - see the very steady increase since the start of the observations.
b) everybody agress on the importance of methane, it is still highly unlikely that it will be more important to longterm climate changes than co2.
c) the development of carbon sinks and sources is of such an outmost importance, that there are several projects monitoring their development, see for example
http://www.globalcarbonproject.org/index.htm
All the best,
w
On February 06 2012 12:25 shuurai wrote:
Arctic sea ice extent has been lowest in 2007 and has not gotten less ever since. So, while it may make for a great talking point, we probably will not see the arctic ice free in 30 years. I'd be willing to wager.
The claim that millions of people depend on glaciers for water, all the while these glaciers are not supposed to melt, is downright hilarious! But yea, impressionable people make for good...impressions, I guess.
Arctic sea ice extent has been lowest in 2007 and has not gotten less ever since. So, while it may make for a great talking point, we probably will not see the arctic ice free in 30 years. I'd be willing to wager.
The claim that millions of people depend on glaciers for water, all the while these glaciers are not supposed to melt, is downright hilarious! But yea, impressionable people make for good...impressions, I guess.
Hi Shuurai,
interesting point.
Clearly a system that oscillates and is highly weather driven (as is summer sea ice formation) is noisy and one would not expect a decrease that goes monotonely in time.
Still, the number of record low years in the 2000 -2010 decade wrt older climatology is astounding. It appears that the Arctic is experiencing global warming faster or that additionally to the global warming signal there is a strong warming anomaly on top. As to the exact year of sea ice free summer: that is anybodys guess. Scientist have been surprised how low the summer sea ice extent was in 2007, nature was much much faster than all original expectations and projections (people thought the 2080s).
We have to acknowledge now, that a system as in the Arctic that now consists of thin and young sea ice will fluctuate significantly more than in the past, with a variability that makes predictions very hard to do.
Additionally, sea ice extent is a "soft" variable, sea ice volume would be much smoother and with less variations. Unfortunately, there are no reliable data sets on sea ice volume evolution yet, this is where science is working at, at the moment.
Best
w
On February 05 2012 23:13 Acasta wrote:
Hi dabbeljuh,
I believe in human-made climate change, and i think your research is very important, as understanding a problem and making everyone aware that there is one, is the first and most important step for solving it.
I'm making my B.Sc. in Geoscience right now, want to do my Master in Applied Geophysics (so may be working for the oil industry) and I'm very interested in any kind of energy related issue.
I would like your personal opinion on this:
The most important contributor to climate change is the burning of fossil fuels as energy-sources (oil, gas and coal); and while this affects the climate it also affects our society, lifestyle, and view of what humanity is capable (always expecting economic growth even though our energy sources are limited).
With the words of Nobel Laureate Richard Smalley: "Energy is the single most important challenge facing humanity today" and cheap energy is also a very big part of the solution for various other problems of humanity (Water, Food, Wars/Terrorism).
(see Lecture of Richard Smalley about Energy for more information)
Now that we have passed peak oil, energy is just going to get more expensive, and while we are currently not able to meet our energy demand with renewable energys (and dont unterstand me wrong; renewable energies have to be the solution and research should get more funded), we remain dependent on fossil fuels for at least the next 40 years.
So: Aren't the problems deriving from not having cheap energy (wars, financial crisis, a step backwards in solving the water and food problem) less important than the problems caused by fossil fuels (climate change, oil spills, environmental damage caused by oil sand)?
This is a very difficult question and i don't think that there is a perfect answer; (hard to quantify the problems and damage)
In my opinion the solution has to be a compromise between both, fossil fuels and environment (obviously regulating our energy demand will also be important); but fossil fuels are to important for the next 40 years to discard them in favor of climate change.
I would like your opinion (and the opinon of others) on that :-)
Thanks for reading :D
Hi dabbeljuh,
I believe in human-made climate change, and i think your research is very important, as understanding a problem and making everyone aware that there is one, is the first and most important step for solving it.
I'm making my B.Sc. in Geoscience right now, want to do my Master in Applied Geophysics (so may be working for the oil industry) and I'm very interested in any kind of energy related issue.
I would like your personal opinion on this:
The most important contributor to climate change is the burning of fossil fuels as energy-sources (oil, gas and coal); and while this affects the climate it also affects our society, lifestyle, and view of what humanity is capable (always expecting economic growth even though our energy sources are limited).
With the words of Nobel Laureate Richard Smalley: "Energy is the single most important challenge facing humanity today" and cheap energy is also a very big part of the solution for various other problems of humanity (Water, Food, Wars/Terrorism).
(see Lecture of Richard Smalley about Energy for more information)
Now that we have passed peak oil, energy is just going to get more expensive, and while we are currently not able to meet our energy demand with renewable energys (and dont unterstand me wrong; renewable energies have to be the solution and research should get more funded), we remain dependent on fossil fuels for at least the next 40 years.
So: Aren't the problems deriving from not having cheap energy (wars, financial crisis, a step backwards in solving the water and food problem) less important than the problems caused by fossil fuels (climate change, oil spills, environmental damage caused by oil sand)?
This is a very difficult question and i don't think that there is a perfect answer; (hard to quantify the problems and damage)
In my opinion the solution has to be a compromise between both, fossil fuels and environment (obviously regulating our energy demand will also be important); but fossil fuels are to important for the next 40 years to discard them in favor of climate change.
I would like your opinion (and the opinon of others) on that :-)
Thanks for reading :D
Hi Acasta.
One answer: the shortage of fossil fuels will not help us at any point, there is enough oil, gas and especially coal (!) on Earth that accumulated over millenia and that will perturb the Earths climate massively if released in too short a time frame.
And there are things that people do not recognize; we are not onlz talking about changes until 2100, if humankind releases all fossil fuels available, the science (not models, data from the past) is pretty robust that we will sea level rise on the order of dozens of meters (and on the time scale of millenia). We are massively changing the Earths climate and should consider our options and obligations.
The UNFCC (http://en.wikipedia.org/wiki/United_Nations_Framework_Convention_on_Climate_Change ) asks the world community to prevent a rate of change of Earths climate that still allows the adaptation of bio systems (that includes us). That means, we need to maintain adaptation rates that are proportional to governance, finance, GDP +. We see for example, that failed states or states with massive debts just dont have any options to put forward a consistent sustainable policy regime.
We should also think about the level of adaptation that will be possible for future generations. the balance between these two is clearly a point of debate and should be debated in public. Preferably instead of discussion of science results.
Best
W
On February 06 2012 03:10 shuurai wrote:
Unless you are actually aiming for something afield of intellectually honest debate, labeling your opponents as "denialists" is certainly not the hallmark of a scientist.
With that out of the way, I'd like you to address a few points:
1) Quite recently, several key institutions leading the charge have, without much fanfare, revised their forecasts into their very opposites. These include the Climatic Research Unit of East Anglia, of "Climategate" fame, as well as NASA and the UK's Met Office, which now admit that their data shows no warming trend in the past 15 years -- which, almost needless to say, flies straight in the face of their highly alarmist claims dating back to the turn of the millenium. That in essence leaves us with only one conclusion: Their models are nowhere near accurate, and should thus not be taken for gospel. Can you possibly dispute that?
..
Unless you are actually aiming for something afield of intellectually honest debate, labeling your opponents as "denialists" is certainly not the hallmark of a scientist.
With that out of the way, I'd like you to address a few points:
1) Quite recently, several key institutions leading the charge have, without much fanfare, revised their forecasts into their very opposites. These include the Climatic Research Unit of East Anglia, of "Climategate" fame, as well as NASA and the UK's Met Office, which now admit that their data shows no warming trend in the past 15 years -- which, almost needless to say, flies straight in the face of their highly alarmist claims dating back to the turn of the millenium. That in essence leaves us with only one conclusion: Their models are nowhere near accurate, and should thus not be taken for gospel. Can you possibly dispute that?
..
hi shuurai,
sorry I cannot adress all your points, because I am kind of busy and you seem to be very convinced that climate change science is a scam. I will still adress your point 1, because it might be misleading to more:
The evolution of global averaged temperature trends is a combination of signal and noise. Think about daily + yearly cycle as an easy noise, and the signal is the proven and measured warming trend of the 20th century. There is also longterm variation in the system, the ocean has cycles that are on the length scale of years to decades. A famous multiyear variation is the El Nino / La Nina oscillation. This means, that on top of a trend you have fluctuations that naturally increase / decrease the strength of the trend .
Think about it: even if September 22 would be colder than september 21 (noise) you would not dare to say that Winter wont be colder than summer (signal, forcing due to orbit of the Earth).
The same holds for periods of stronger and weaker coolings, it does not invalidate the signal. The communication problem is: to give the best and most robust analysis to the public, scientists usually take the mean of all their models, so call ensemble average. This gives the best estimate of the true signal. It also averages the noise, because one model has a La Nina, one model has a El Nino, and so forth. the resulting graphs are "too smooth" to be realistic, they are also not to be interpreted as a forecase for a realistic realization of the stochastic system Earth. They should be interpreted as our best guess as to how strong the underlying forcing due to human made CO2. If you look at normal climate model output, they have periods like the 2000s with a slightly decreased trend all over the place. Its just natural variability.
I hope that helps a little bit
w
The 'models' mostly consist of CO2 and an arbitrary forcing factor instead of considering the wider picture, which in itself makes any distinction between signal and noise uneducated guesswork. Have you ever looked at the model 'code' leaked from UEA?
this is blatantly wrong. I have worked on creating GCM code, thank you very much, I dont have to look at leaked model code from other people. Or models incorporate flow solvers for atmosphere and ocean, a radiative model, cloud models, vegetation models, ocean biogeochemistry models and are probably the most complex tool of Earth System description that mankind has ever made up. They are far from perfect as is the case for any evolving science, so there are bugs. They are still the best guess anybody has ever brought forward as to how Earths complex system works.
I'd love to see the model that predicted what has occurred. All I can seem to find are prophecies of disaster which failed to manifest. Please provide me with a pointer to a model that got it right.
I hope that you can access the papers, but here it goes "Model-based evidence of deep-ocean heat uptake during surface-temperature hiatus periods"
http://www.nature.com/nclimate/journal/v1/n7/full/nclimate1229.html
Here we analyse twenty-first-century climate-model simulations that maintain a consistent radiative imbalance at the top-of-atmosphere of about 1 W m−2 as observed for the past decade. Eight decades with a slightly negative global mean surface-temperature trend show that the ocean above 300 m takes up significantly less heat whereas the ocean below 300 m takes up significantly more, compared with non-hiatus decades. The model provides a plausible depiction of processes in the climate system causing the hiatus periods, and indicates that a hiatus period is a relatively common climate phenomenon and may be linked to La Niña-like conditions.
regards,
w
and to adress your other two questions:
2) There is ample evidence for historical periods of substantially more warmth in history (e.g. Medieval Warm Period, Holocene Optimum) , none of which have been caused by industrialization and none of which resulted in ecological disaster -- to the contrary, in fact. Knowing that vast changes have occurred quite naturally, and without disastrous results, what arguments are there to justify the current efforts to "fix" the climate?
different times, different forcings, different worlds.
a) the fact that in the past the climate reacted sensitiv to changes in forcings (orbit, volcanic) makes the case even better, that the ver strong , measurable change in forcing that humans cause will lead to a change in climate.
b) the rate of change is much faster than everything related to orbital changes, thus the biosphere has much less time to adapt.
c) the earth is overcrowded and polluted in the sense that we are killing biosphere resilience left and right. this _might_ lead to less resilience of the biosphere, that is something that we just will see.
3) Ice cores, providing us with the longest historical temperature records available, clearly indicate a larger cycle of about 100.000 years of which roughly 10.000 tend to be "interglacials", i.e. times in between ice ages (The underlying theory of which, "Milankovitch Cycles", now is being recognized by the likes of NASA et al btw...). What's more, the end of the current interglacial is just about overdue, making excessive future cooling a very likely -- and very hostile -- scenario, calling for its very own preparations in stark contrast to those for "global warming". If you discard this scenario, on what grounds?
nothing to answer here: the long term glacial / interglaical cycles are dominated by orbital forcing changes that are enforced by co concentration changes.
it is true that the end of the current cycle is due in the next 2000 to 5000 years. it is also true that the change into a glacial is so slow that the rate with which we heat the earth is 2 orders higher.
so, nobody discards any scenario, it is just not happening anytime soon. since about 100 and for the next hundreds of year, the major forcing agent (bar a major volcano or a methane reaction) will be co2.
w
dear shuurai,
a) yes, Mann's first reconstruction had some errors, no, nobody has ever shown that this statistical errors were significant. all published reconstructions show the same signal, 20c is warmer then the last 1k years and the warming rate is unprecedented. There are reconstructions for global SATs (mann is NH only), there are new ones by climate sceptical physicists that resulted in the exactly same result : earth is warming. So stop beating this very dead horse, please.
b) carbon leads temperature: again, you either refuse to understand simple science (Bachelor level) or you just want to blatantly lie to people: every climate scientist starting from BA level knows that the glacial - interglaical cycles were initialised by temperature anomalies due to orbital changes. those temperature anomalies were enhanced by an ocean - carbon feedback that led to more co2 in the atmosphere, which in turn (this is ridicously easy and basic physics, radiative transfer models anyone?) lead to warmer atmosphere. this has been discussed a billion time in this thread, please refrain from repeating things that are simply wrong. No climate scientist ever disputed your facts, you just fail to put them into context.
c) computer models are anything but holy scripture, please stop embarassing yourself. do you know the Isaac NEwton Institute for MAthematics in Cambridge? The Pure and Applied MAthematics Institute in Los Angeles? The insitute for applied science in Jerusalem? These are just a few institutions which are NON climate science institutions which have hosted big workshops to analyse climate model uncertainties in the past years. Scientists discuss, talk, they will find problems and might find solutions. We are not part of a big conspiracy, even if this does not fit into your worldview °
d) the ipcc AR5 will have 4 chapters on model results, 9 on data and process understanding. so, even if are the smartest person on the world and you can prove that everything that is within contemporary GCMs is wrong, this will not invalidate anything concerning paleo evidence, 20c detection and process understanding.
e)the supposed conspiracy theory to prevent the truth to be told: If I would be able to write a paper that would show that the Climate problem is bogus and that 20c warming can be explained by a process that is unrelated to anthropogenic CO", I would probably get the physics nobel prize and would be the most famous scientist on this planet. Do you really think this could be prevented in an open world with hundreds of new climate science related PhDs each year? REally? You seriously have no idea of how science works °J°
W
On February 09 2012 02:17 Crushinator wrote:
I am skeptical by nature, and have been skeptical about man made global warming in the past. I have sought some information about it, however, and I am fairly confident that man made global warming is accurate. That is, man has been a significant factor in the recent warming period. But while gathering information there was one thing that bugged me. Please forgive me, because I'm sure this is realy simplistic:
Even if it is all true, why should we not just accept that its going to get a bit warmer? It seems to me that cutting down on CO2 at all, or enough to have a significant effect, is going to be an impossible task for various political, economic and demographic reasons. Would it not be better to simply prepare for a warmer future rather than to attempt to prevent the inevitable?
Presumably the temperature will not rise to unlivable conditions, and will just reach some equilibrium higher than what it is now. We would have to move away from current coastal regions maybe build some dykes and what not, probably abandon some islands, but that doesn't seem that troublesome to me. Forgive the jest, but to me it isn't such a big deal that polar bears are going to be getting a bit hot. Also, why do I never hear anyone speak of potential positive effects of a warmer climate? Am I not looking hard enough? In short, why should I care? If someone could point out why I am an idiot for thinking this way, that would be lovely.
I am skeptical by nature, and have been skeptical about man made global warming in the past. I have sought some information about it, however, and I am fairly confident that man made global warming is accurate. That is, man has been a significant factor in the recent warming period. But while gathering information there was one thing that bugged me. Please forgive me, because I'm sure this is realy simplistic:
Even if it is all true, why should we not just accept that its going to get a bit warmer? It seems to me that cutting down on CO2 at all, or enough to have a significant effect, is going to be an impossible task for various political, economic and demographic reasons. Would it not be better to simply prepare for a warmer future rather than to attempt to prevent the inevitable?
Presumably the temperature will not rise to unlivable conditions, and will just reach some equilibrium higher than what it is now. We would have to move away from current coastal regions maybe build some dykes and what not, probably abandon some islands, but that doesn't seem that troublesome to me. Forgive the jest, but to me it isn't such a big deal that polar bears are going to be getting a bit hot. Also, why do I never hear anyone speak of potential positive effects of a warmer climate? Am I not looking hard enough? In short, why should I care? If someone could point out why I am an idiot for thinking this way, that would be lovely.
dear crushinator,
its good questiond and something that is worth to be discussed on a political level.
you cannot get a scientific answer to what level of sea level rise or temperature change or biosphere capacity or ocean acidification (you get the point °) is acceptable. scientists can only supply a best guess of what will happen if we continue a certain path of global emissions. I believe that the science that analyzes the costs and dangers of near-term climate change is still very young. I would not believe single numbers that have been brought forward as to how much cc will cost in global GDP in 2100.
I still believe, that there is the danger of overextending Earths ability to cope with the demands a 9 billion population will put upon Earth very soon. I for example would rank the dangers as follows:
- precipitation changes ( we just do not understand precipitation well enough to do a good forecast, so I fear we might get surprised in one way or the other)
- sea level rise (longterm): a lot of people live close to the seas!
- ocean acidification: again, its more caution than knowledge, we just dont know what will happen with the food chain in the oceans if the acidify the ocean to much.
temperature changes directly are probablz the lest dangerous consequence of climate change, people can adapt to temperature quite good, as can be seen by people living in alaska and kenia
hope that helps a bit
best
w
On February 09 2012 10:11 cLutZ wrote:
Obviously its impossible for me to know if you answered this earlier, but maybe you did.
What events could occur that would "disprove" the AGW theory. Basically, what is the Higgs-Boson test (Standard model goes out the window if they can't find it) for AGW?
In other words, is this even a science, or is it more an art?
Obviously its impossible for me to know if you answered this earlier, but maybe you did.
What events could occur that would "disprove" the AGW theory. Basically, what is the Higgs-Boson test (Standard model goes out the window if they can't find it) for AGW?
In other words, is this even a science, or is it more an art?
hi clutz, very good (popperish~) question, that we discussed a lot between us new-to-the-field PhD students.
I fear the answer is not so "simple" as with the Higgs Boson test (and I would argue that even if the CERn guys dont find it now in the expected energy range that would not invalidate all the good results the standard model brought forward).
I think the closest thing would be if we see a 20 year / 30 year cooling without external signal (i.e. without strong decrease of solar influence or strong volcanoes), that means if we could identify a 50/60 year internal oscillation of the coupled Earth system that could explain the strong warming in the second half of the 20c and would then explain the cooling over the first 30 years of the 21c. We have not seen this type of very lpng multidecadal pattern yet, it could be a problem of the models.
A second thing would be if we can really identify a stronger control of clouds through cosmic rays and if we then could identify a trend in this rays. these are two ifs but still, this would also put up a valid second theory as to what the 20c warming means.
I hope that helps, if it is too unclear, just come back to me,
w
