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Post by steve on Apr 21, 2009 17:44:52 GMT
Why is it a "scripted" response? Surely you are inventing a controversy out of nothing. I thought it was "common sense" that warming at the surface increased evapo-transpiration and convection resulting in more warming aloft. Proper references are hard to find because most of the published references are likely to be old, and all the current fuss is about the warming due to CO2. The best accessible reference is probably from your favourite bloke: www.llnl.gov/str/JulAug02/Santer.htmlImage: www.llnl.gov/str/JulAug02/gifs/Santer4.jpgwhich shows that for both solar and CO2 warming, the models show less warming at the surface than in the mid-troposphere, whereas in the stratosphere, the increased solar warms the stratosphere whereas the increased CO2 cools the stratosphere. In other words, whether or not the models are right about the different trend says nothing about CO2 in particular, and says more about the response of the models to warming in general. By including the above link I don't mean to open a discussion about Santer showing that observations are not out of line with the models any more. Quite simply. . . .I believe. . . .your comments are correct if and only if you rate CO2 as an important greenhouse gas. Ultimately the conclusion that increased solar radiation would raise temperatures in the upper atmosphere is because you believe that is where the heat is getting trapped. If you believe that the water cycle is the dominant climate force and continues to be in face of increased solar warming; then you would conclude that the warming would occur very close to the surface. . . .where all evidence suggests it has. The mid atmosphere warming predicted by CO2 models would produce the same result no matter the source of heat. Thus your argument begs the question. Well thank you for at least some support against Magellan's "obfuscation" remark. My understanding is that because CO2 is a "greenhouse gas" it effectively cuts down the escape of radiation where temperatures fall with height and increases the escape of radiation where temperatures rise with height. I've discussed the reasons in as much detail as I can in various other threads so I won't expand the explanation further here. On the other hand, increased solar doesn't change the "radiative properties" of the atmosphere, so the warmth at the surface will tend to spread throughout the whole atmosphere. So the CO2 fingerprint is the stratospheric cooling. The question about mid-troposphere warming is more about whether the models are falsified.
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Post by magellan on Apr 21, 2009 22:24:11 GMT
Why is it a "scripted" response? Surely you are inventing a controversy out of nothing. I thought it was "common sense" that warming at the surface increased evapo-transpiration and convection resulting in more warming aloft. Proper references are hard to find because most of the published references are likely to be old, and all the current fuss is about the warming due to CO2. The best accessible reference is probably from your favourite bloke: www.llnl.gov/str/JulAug02/Santer.htmlImage: www.llnl.gov/str/JulAug02/gifs/Santer4.jpgwhich shows that for both solar and CO2 warming, the models show less warming at the surface than in the mid-troposphere, whereas in the stratosphere, the increased solar warms the stratosphere whereas the increased CO2 cools the stratosphere. In other words, whether or not the models are right about the different trend says nothing about CO2 in particular, and says more about the response of the models to warming in general. By including the above link I don't mean to open a discussion about Santer showing that observations are not out of line with the models any more. Quite simply. . . .I believe. . . .your comments are correct if and only if you rate CO2 as an important greenhouse gas. Ultimately the conclusion that increased solar radiation would raise temperatures in the upper atmosphere is because you believe that is where the heat is getting trapped. If you believe that the water cycle is the dominant climate force and continues to be in face of increased solar warming; then you would conclude that the warming would occur very close to the surface. . . .where all evidence suggests it has. The mid atmosphere warming predicted by CO2 models would produce the same result no matter the source of heat. Thus your argument begs the question. The models supposedly encompass the basic "high school physics" warmers keep yapping about. Are you now saying the models may not be so "basic" after all? The stratosphere was not in the OT, but since you bring it up, go ahead, post the data showing it is cooling as predicted. Not the ubiquitous "long term trend" please, which is more bastardizing of linear regression. Cooling occurred at the same time of the last two major volcanoes, in steps; a totally "natural" phenomenon. How much has it cooled since then? Warmers must account for the missing heat. Ignoring this very inconvenient observation does not help your argument. BTW, how many AGW fingerprints are there?
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Post by steve on Apr 22, 2009 11:05:43 GMT
The stratosphere was not in the OT, but since you bring it up... No, you brought it up by introducing a plot purporting to be of mid-troposphere warming which is in fact a plot of the average of a warmer mid-troposphere and a cooler stratosphere, and then failing to accept what it was despite confirmations from the likes of Roy Spencer.
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Post by magellan on Apr 22, 2009 13:30:07 GMT
The stratosphere was not in the OT, but since you bring it up... No, you brought it up by introducing a plot purporting to be of mid-troposphere warming which is in fact a plot of the average of a warmer mid-troposphere and a cooler stratosphere, and then failing to accept what it was despite confirmations from the likes of Roy Spencer. Actually no. You said T2 is "contaminated" by the stratosphere. And since you've brought up Spencer: www.drroyspencer.com/2009/04/clouds-cool-the-climate-system%E2%80%A6but-amplify-global-warming/The cooling step changes observed in the stratosphere was caused by volcanic activity. There is zero evidence CO2 had anything to do with it. Since 1994 there has been no cooling trend that supports the CO2 AGW hypothesis. None. Nada. You also stated in another post LT observations agree with climate models but gave no references. Do you have them?
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jtom
Level 3 Rank
Posts: 248
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Post by jtom on Apr 22, 2009 15:58:35 GMT
I'd like to step back and ask a question - not a challenge or a 'gotcha', but a real question.
Whether you believe in CO2 global warming or not, global temps have gone down over the last couple of years. Why? I can see it happening if solar irradiance dropped, or a major volcano, a change in earth's albedo, oceans soaking up the energy, a transfer of energy to the ice caps, other such event, but essentially none seem to have happened.. The most likely thing I can come up with is a change in albedo, but data from different sources disagree as to whether the albedo has gone up or down.
Please realize that 'natural variance' is just a vague term - there is always some physical processes going on which bring about the change.
So where has the energy gone (particularly if you do ascribe to CO2 warming)?
Any thoughts?
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Post by steve on Apr 22, 2009 16:55:07 GMT
I'd like to step back and ask a question - not a challenge or a 'gotcha', but a real question. Whether you believe in CO2 global warming or not, global temps have gone down over the last couple of years. Why? I can see it happening if solar irradiance dropped, or a major volcano, a change in earth's albedo, oceans soaking up the energy, a transfer of energy to the ice caps, other such event, but essentially none seem to have happened.. The most likely thing I can come up with is a change in albedo, but data from different sources disagree as to whether the albedo has gone up or down. Please realize that 'natural variance' is just a vague term - there is always some physical processes going on which bring about the change. So where has the energy gone (particularly if you do ascribe to CO2 warming)? Any thoughts? I guess "Natural variation" is a kind of catch-all phrase for complex interrelated things that have always happened but that we can't accurately observe, characterise or describe. Another question is if you take the current temperatures and tilt it slightly to the right (to remove a CO2 warming trend) does the temperature variation look unusual as compared with a period when CO2 was not changing much? Really we wouldn't expect variability now to be that different from variability in many past times. To answer the question, perhaps the cooler temperatures being recorded *could* be a combination of, in no particular order, the following variations: - ocean currents bringing more cooler water to the surface than average; - a variation in convection that changes cloud cover (perhaps related to the ocean changes) that reflects away more sunlight or that holds in less heat at night, and changes in mid-troposphere water vapour levels that reduces the greenhouse effect; - a change in the amount, type and location of aerosols. Many things can affect this: forest fires, volcanic activity, plant/planckton emissions (eg. dimethyl sulphide (DMS)), amount of rainfall that removes the aerosols, change in winds that move the aerosols around. These aerosols have various effects on cloud formation and solar radiation which could cause relative cooling for a period; - low solar activity, with secondary effects on the upper atmosphere (perhaps including upper atmosphere chemistry changes). I could think of lots of other reasons (none of which I am advocating as an important influence at the moment), and clearly a lot of the effects are interrelated. Eg. lots of rain over a continent might increase river outflow which might affect planckton growth which might affect DMS production which might affect cloud creation.
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Post by nautonnier on Apr 22, 2009 18:44:08 GMT
I'd like to step back and ask a question - not a challenge or a 'gotcha', but a real question. Whether you believe in CO2 global warming or not, global temps have gone down over the last couple of years. Why? I can see it happening if solar irradiance dropped, or a major volcano, a change in earth's albedo, oceans soaking up the energy, a transfer of energy to the ice caps, other such event, but essentially none seem to have happened.. The most likely thing I can come up with is a change in albedo, but data from different sources disagree as to whether the albedo has gone up or down. Please realize that 'natural variance' is just a vague term - there is always some physical processes going on which bring about the change. So where has the energy gone (particularly if you do ascribe to CO2 warming)? Any thoughts? I guess "Natural variation" is a kind of catch-all phrase for complex interrelated things that have always happened but that we can't accurately observe, characterise or describe. Another question is if you take the current temperatures and tilt it slightly to the right (to remove a CO2 warming trend) does the temperature variation look unusual as compared with a period when CO2 was not changing much? Really we wouldn't expect variability now to be that different from variability in many past times. To answer the question, perhaps the cooler temperatures being recorded *could* be a combination of, in no particular order, the following variations: - ocean currents bringing more cooler water to the surface than average; - a variation in convection that changes cloud cover (perhaps related to the ocean changes) that reflects away more sunlight or that holds in less heat at night, and changes in mid-troposphere water vapour levels that reduces the greenhouse effect; - a change in the amount, type and location of aerosols. Many things can affect this: forest fires, volcanic activity, plant/planckton emissions (eg. dimethyl sulphide (DMS)), amount of rainfall that removes the aerosols, change in winds that move the aerosols around. These aerosols have various effects on cloud formation and solar radiation which could cause relative cooling for a period; - low solar activity, with secondary effects on the upper atmosphere (perhaps including upper atmosphere chemistry changes). I could think of lots of other reasons (none of which I am advocating as an important influence at the moment), and clearly a lot of the effects are interrelated. Eg. lots of rain over a continent might increase river outflow which might affect planckton growth which might affect DMS production which might affect cloud creation. So in other words there are many other natural climate drivers that can overwhelm AGW?
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Post by FurryCatHerder on Apr 22, 2009 18:59:14 GMT
So in other words there are many other natural climate drivers that can overwhelm AGW? I don't think anyone disputes that -- a massive volcanic eruption would do very nicely. HOWEVER, we can't count on a constant string of volcanic eruptions, never ending solar minima, upwelling of cold ocean water for centuries to come, etc, etc, to bail us out. So long as CO2 levels keep rising, the amount of warming that will occur when all those extraordinary events stop is going to increase. See this article of mine -- furrycatherder.livejournal.com/66935.html -- for a longer explanation.
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Post by slh1234 on Apr 22, 2009 19:32:01 GMT
So in other words there are many other natural climate drivers that can overwhelm AGW? I don't think anyone disputes that -- a massive volcanic eruption would do very nicely. HOWEVER, we can't count on a constant string of volcanic eruptions, never ending solar minima, upwelling of cold ocean water for centuries to come, etc, etc, to bail us out. So long as CO2 levels keep rising, the amount of warming that will occur when all those extraordinary events stop is going to increase. See this article of mine -- furrycatherder.livejournal.com/66935.html -- for a longer explanation. I think that showed your political views clearly enough that your opinions here now make more sense. But just a question, in your article, do you see the parts that are really just your opinion? or the assertions that you make just because that's what you think? Is disagreement with that what makes someone "maladaptive?"
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Post by nautonnier on Apr 22, 2009 20:41:47 GMT
So in other words there are many other natural climate drivers that can overwhelm AGW? I don't think anyone disputes that -- a massive volcanic eruption would do very nicely. HOWEVER, we can't count on a constant string of volcanic eruptions, never ending solar minima, upwelling of cold ocean water for centuries to come, etc, etc, to bail us out. So long as CO2 levels keep rising, the amount of warming that will occur when all those extraordinary events stop is going to increase. See this article of mine -- furrycatherder.livejournal.com/66935.html -- for a longer explanation. Strange really as we haven't had such a string of volcanic eruptions that could cause such an overwhelming change that the AGW has been stopped then reversed. Must be something else..... and whatever it is - it is more effective than the recent 'catastrophic rise' in green house gas emissions. Perhaps it was in the warming mode in the last 20 years of the 20th century? As in your article you note the cooling effect of the Sun but avoid talking about its warming effects.
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Post by socold on Apr 22, 2009 20:58:27 GMT
I would say the temperature pattern is consistant with a warming trend of 0.15C/decade with declining ENSO since 2003 and solar minimum in last 2 years. We'll find out when ENSO goes neutral and solar minimum is over because temperature should then be higher.
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Post by tacoman25 on Apr 23, 2009 1:02:01 GMT
I'd like to step back and ask a question - not a challenge or a 'gotcha', but a real question. Whether you believe in CO2 global warming or not, global temps have gone down over the last couple of years. Why? I can see it happening if solar irradiance dropped, or a major volcano, a change in earth's albedo, oceans soaking up the energy, a transfer of energy to the ice caps, other such event, but essentially none seem to have happened.. The most likely thing I can come up with is a change in albedo, but data from different sources disagree as to whether the albedo has gone up or down. Please realize that 'natural variance' is just a vague term - there is always some physical processes going on which bring about the change. So where has the energy gone (particularly if you do ascribe to CO2 warming)? Any thoughts? I guess "Natural variation" is a kind of catch-all phrase for complex interrelated things that have always happened but that we can't accurately observe, characterise or describe. Another question is if you take the current temperatures and tilt it slightly to the right (to remove a CO2 warming trend) does the temperature variation look unusual as compared with a period when CO2 was not changing much? Really we wouldn't expect variability now to be that different from variability in many past times. To answer the question, perhaps the cooler temperatures being recorded *could* be a combination of, in no particular order, the following variations: - ocean currents bringing more cooler water to the surface than average; - a variation in convection that changes cloud cover (perhaps related to the ocean changes) that reflects away more sunlight or that holds in less heat at night, and changes in mid-troposphere water vapour levels that reduces the greenhouse effect; - a change in the amount, type and location of aerosols. Many things can affect this: forest fires, volcanic activity, plant/planckton emissions (eg. dimethyl sulphide (DMS)), amount of rainfall that removes the aerosols, change in winds that move the aerosols around. These aerosols have various effects on cloud formation and solar radiation which could cause relative cooling for a period; - low solar activity, with secondary effects on the upper atmosphere (perhaps including upper atmosphere chemistry changes). I could think of lots of other reasons (none of which I am advocating as an important influence at the moment), and clearly a lot of the effects are interrelated. Eg. lots of rain over a continent might increase river outflow which might affect planckton growth which might affect DMS production which might affect cloud creation. None of those possible reasons you list qualify as strong enough to overcome CO2 over a decadal time scale, or at least they are not very likely to, according to IPCC forcing estimates.
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jtom
Level 3 Rank
Posts: 248
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Post by jtom on Apr 23, 2009 1:03:04 GMT
nautonnier has a point - unless someone can come up with a significant driver for cooling, it looks like a combination of *minor* things may be overwhelming any CO2 warming, which raises questions as to just how sensitive the climate is to CO2. Otherwise, one would have to believe that a combination of anomalies made the earth warmer a decade ago, and we are slowly cooling back down to 'normal'.
Either the energy isn't getting here, or something (the oceans?) is soaking it up.
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Post by tacoman25 on Apr 23, 2009 1:05:28 GMT
So in other words there are many other natural climate drivers that can overwhelm AGW? I don't think anyone disputes that -- a massive volcanic eruption would do very nicely. HOWEVER, we can't count on a constant string of volcanic eruptions, never ending solar minima, upwelling of cold ocean water for centuries to come, etc, etc, to bail us out. So long as CO2 levels keep rising, the amount of warming that will occur when all those extraordinary events stop is going to increase. See this article of mine -- furrycatherder.livejournal.com/66935.html -- for a longer explanation. 1. There has been no signficant, climate-altering volcanic eruption since 1991's Pinatubo. 2. Solar minima only began around 2007. Doesn't explain the flattening global temps before that. 3. What upwelling cold water? -PDO? That didn't start until late 2007.
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Post by tacoman25 on Apr 23, 2009 1:09:10 GMT
I would say the temperature pattern is consistant with a warming trend of 0.15C/decade with declining ENSO since 2003 and solar minimum in last 2 years. We'll find out when ENSO goes neutral and solar minimum is over because temperature should then be higher. There is nothing consistent with the 2000s compared to the 1990s and 1980s. AGAIN, when ENSO is factored out, something else caused temps to start leveling off in the late 1990s.
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