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Post by steve on May 11, 2013 9:39:38 GMT
Duwayne, Scientists have always been "quietly" making such statements. This is what Trenberth said in 1999: www.gcrio.org/CONSEQUENCES/vol5no1/extreme.htmlIn a "personal perspective" within this longer article he says: So although one might argue that the recent evidence is against this hypothesis, it was put in a relatively measured way.
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Post by steve on May 11, 2013 8:59:34 GMT
Whose measure are we comparing against? Different institutions have different methods for measuring extent. What was their minimum last year?
For the record, in another poll I'm involved in I simply guessed "same as last year".
It's based purely on ice volume being the same this year as last year.
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Post by steve on May 5, 2013 18:01:53 GMT
nautonnier,
It is not me who is claiming that all the LW energy incident on the ocean surface simply results in water being evaporated. It is other people.
Other people are claiming that the LW radiation *cannot* influence the temperature of the water on the (thin) argument that LW can only penetrate a tenth or hundredth of a millimetre into water and that therefore it cannot influence its temperature.
I think that much of the incident energy *does* influence the ocean temperature.
*If* I am wrong then this evaporated water *must* end up in the atmosphere for some time. But if it releases its energy condensing near the surface, then the energy goes into warming the air and water droplets - the water droplets then influence the temperature of the ocean.
You cannot just magic this energy away no matter how you try.
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Post by steve on May 5, 2013 17:51:47 GMT
cuttydyer,
Yes the co2"science" project has been mentioned many times before.
Basically, they look at proxy papers. If the paper says it may have been warmer or drier than some period in the 20th Century for a short period some time between 850 and 1450AD they will say "aha!!! this proves the MWP was present in this location".
Given that many of the proxies also show large periods of time when temperatures were similar or cooler, and given that the late 20th Century and early 21st Century warming is not picked up by many proxies, the average of the proxies tend to back up the findings of folk such as Esper, Mann and Marcott - that temperatures now are globally as warm or warmer than any time in the last millennium.
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Post by steve on May 4, 2013 7:55:00 GMT
Icefisher,
Correction: The testimony said there was a possibility of 1C warming by now relative to 1951-1980. The actual warming was 0.6C
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Post by steve on May 4, 2013 7:51:29 GMT
Steve, you have a minor logic problem: "Question: Does all the energy from the infrared radiation of the atmosphere at the sea surface go into evaporating water?
If it does:
Latent heat of evaporation of water 2260 J/g 1mm of water over 1m^2 equates to 1kg of water. Therefore 300W/m^2 "back radiation" would evaporate 1kg of water per 7500 seconds.
However, average rainfall per year is around 1 metre or 1000mm
If back radiation all goes into evaporating water, it would take 7.5 million seconds to evaporate this amount of water.
This is only 86 days - or 130 days taking into account the ocean is 2/3 of the planet.
Conclusion - there is not enough rainfall if back radiation only evaporates water.
Secondary conclusion, therefore some of the energy from back radiation *must* remain in the water for at least some time allowing it to be conducted or mixed into the deeper layers of the ocean. " Steve. 1. Infrared does not penetrate into water - the most it can do is excite surface molecules that will evaporate if warmed sufficiently. Wishing it were not so will not change that. 2. Water will evaporate in the absence of infrared if the water vapor pressure is low (i.e. dry air). 3. Ice will sublimate directly into the atmosphere if the water vapor pressure is low (i.e. dry air). 4. Water will evaporate readily from hot surfaces such as rocks due to direct sensible heat input supplying the latent heat of evaporation. 5. As we both agreed - water will evaporate due to warming by short wave radiation from the Sun. Therefore from these points there would appear to be a strong case far far more water entering the atmosphere than your calculation would suggest as due only to downwelling infrared. You have provided empirical proof that the 'back radiation' or 'downwelling longwave radiation' does not exist. nautonnier, My logical issue is quite clear. The energy from the radiation is not reflected and it does not disappear. So it is absorbed. The absorption spectrum of water indicates it is absorbed - albeit most is absorbed in much less than a millimetre. Now water is a very very complex material, and given a large amount of energy being absorbed in a thin layer neither I nor you have adequately explained what happens. If, as you say, it evaporates water, then the water it evaporates is *clearly* not seen in the atmosphere in the precipitable water statistics or the rainfall statistics. For your purposes, it is important for you to explain where that water goes, as the water is holding the energy we're discussing. Claes Johnson is a sky dragon slayer who discounts the reality of basic physics laws used in astronomy, particle physics, engineering. It's complete and utter rubbish. Judith Curry tried to turn the Sky Dragon believers around. Roy Spencer continues to work on the Sky Dragon believers. Their efforts have correctly discredited the Sky Dragon promoters in the same way that cold fusion and mmr-autism link has been discredited. Give Sky dragon theories a rest for your own reputation.
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Post by steve on Apr 29, 2013 12:55:42 GMT
As is usual with my maths, it's very "back of the envelop" so happy to revise based on comments. Question: Does all the energy from the infrared radiation of the atmosphere at the sea surface go into evaporating water? If it does: Latent heat of evaporation of water 2260 J/g 1mm of water over 1m^2 equates to 1kg of water. Therefore 300W/m^2 "back radiation" would evaporate 1kg of water per 7500 seconds. However, average rainfall per year is around 1 metre or 1000mm If back radiation all goes into evaporating water, it would take 7.5 million seconds to evaporate this amount of water. This is only 86 days - or 130 days taking into account the ocean is 2/3 of the planet. Conclusion - there is not enough rainfall if back radiation only evaporates water. Secondary conclusion, therefore some of the energy from back radiation *must* remain in the water for at least some time allowing it to be conducted or mixed into the deeper layers of the ocean. I don't think your back of the envelope calculation has come close to reality. First off even if you accept the -18c albedo adjusted (contrary to Stefan Boltzmann equations no ghg surface temperature) you only get net 150watts of backradiation. (390w-240w).
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Post by steve on Apr 29, 2013 12:30:16 GMT
If you look at my last couple of posts I list a few processes whereby a warmer atmosphere could transfer heat to a colder ocean surface. A warmer atmosphere does *not* necessarily have a lower partial pressure for water vapour. You seriously cannot claim that. I have spent a whole *day* trying to dry washing in temperatures of over 30C and the washing was probably damper at the end of the day (not in England, mind you). If the atmosphere is warmed, then there is a one-off reduction in partial pressure and therefore a one-off reduction in ocean heat content as the ocean evaporates to rebalance the humidity levels. Therefore if the atmosphere retains its temperature (due to the energy imbalance caused by excess greenhouse gases) you will end up with a warm atmosphere and, essentially, the same partial pressure for water vapour. That is too hand wavey for me. How much has UV changed? In what way does 5W of UV warm the oceans more than 5W of yellow light? Yes, we know the climate varies naturally in many different ways. Interesting you put "corrections" in quotes. Have a look at how the albedo was calculated in your previous link! All sorts of corrections and assumptions there. That aside, your sentence doesn't make sense. Who has "claimed" a higher rise than, say, the "'corrected'" Levitus data that is quite prominent on the web? Unless the wind is moist - see previous comment. How much water vapour will be evaporated? Bored now - I'm going to do a bit of maths... ""1. The ocean will not warm 'in response to atmospheric warming' the only thing that heats the ocean is shortwave radiation from the Sun - you admitted this yourself Steve. -If you look at my last couple of posts I list a few processes whereby a warmer atmosphere could transfer heat to a colder ocean surface.""Well - please make up your mind. Your response to my direct question was that the only thing that would warm the oceans was short wave radiation from the Sun. Now you wish to revisit that answer as you realize that has destroyed your AGW hypothesis. Your direct question was offered as some sort of defence of magellan's funny ideas. You got a sarcastic answer saying that the Sun had *something* to do with it - not everything. I don't have all the answers, but that doesn't mean that I think it is plausible that a warmer atmosphere has *no* influence on ocean temperatures. In the context of magellan's funny ideas, it's less about what puts energy into the ocean and more about what reduces the rate of energy loss from the ocean. You *cannot* argue with vague generalities. The amount of evaporation is based on the temperature *and* the humidity - don't focus on the temperature and pretend the humidity is irrelevant. Increasing the humidity of warmer air gives you a *one-off* reduction in ocean heat content. Sorry, that doesn't cut the mustard at all. The argument that back radiation only cools the ocean by evaporating moisture *requires* that 3 metres worth of moisture is evaporated per year for every square metre of the planet. But only one metre of rain falls. That calculation excludes evaporation caused by the Sun!!!
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Post by steve on Apr 28, 2013 14:03:10 GMT
I remember the predictions from decades ago because it seemed plausible and after all, "scientists" can't be wrong because they are soooo smart. It is in no way in line with reality and why I began questioning the AGW meme. Stop making up stuff, first produce the predictions and what fulfilled those predictions. Then produce the models/scientists from "many decades" ago that predicted 15+ years of no warming/cooling, particularly the FAILED warming of the atmosphere. Why is it we can find dozens if not hundreds of failed AGW predictions complete with the charts and data but you seem to only give speeches, make up excuses and form new hypotheses to cover for the failed old ones? That is not a prediction. All you folks are doing is making it up as it goes along. Here's one from Hansen 1986. His 1989 Congressional testimony was my first real exposure to hearing a scientist explain and make predictions. There was no internet back then to counter the "consensus". I bought it hook line and sinker for several years. Hansen 1986Oh yes steve, I remember what was on the table. That news article was clearly an error. As you are such an expert, you know this. Therefore your aim is to be deceptive. From the contemporaneous publication (I couldn't find the testimony): www.fas.harvard.edu/~eps5/writing_assignment/CLIMATE_BKGD/Hansen_1988_keypaper.pdfThe warming figures are relative to the 1951-1980 mean. The actual forcing was closest to Scenario B. The actual warming in the 27 years since the testimony is 0.6C Given the status of modelling then, a 40% error in the estimate is pretty good. A big chunk of that error has been understood for over 15 years - since calculations of CO2 forcing were improved and forcing was found to be a bit less than what Hansen thought. I guess people who buy into hype will always buy into hype and tend to go from one extreme to the other. If your original assessment was more measured (like mine was and is) you might have not felt the need to make up for your previous mistakes.
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Post by steve on Apr 28, 2013 10:33:47 GMT
Sorry for insisting, but still is not so clear that mm scale in the figure would be a measure valid for Mauna Loa only? Karlox, The original post says: So it looks like a global figure. The plot title says: So it sounds like it is proportional to the total amount of water in the atmosphere. The obvious problem is that the amount of water should be related to the temperature, not the amount of CO2. So the divergence between the two is not interesting. Beyond that, one would need to know a bit more about the data than what some bloke on a sceptic blog has managed to calculate.
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Post by steve on Apr 27, 2013 13:01:10 GMT
Prove it by listing some sceptic snake oil salesmen.
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Post by steve on Apr 27, 2013 12:59:34 GMT
Indeed not! Which is why Steve McIntyre would quite often be able to find a questionable looking surface station dataset to place before his minions - until the surfacestations project hit the Muller buffers that is. That is why you have to look at lots of pieces of evidence, not just a few. And if you are, for example, trying to compare with the recent 30-50 years, you should look at each 30-50 year period of the past in isolation (as far as can be managed given the resolution of some proxies). There is a tendency to compare the recent 30-50 (or even 100 year) average with the *peak* of any Medieval reference. In short, this is the point I am making. Its not clear the extent of what you are saying Steve. Should we never compare current temperatures to past proxies that entail a great deal of averaging over a significant period of time? If so I disagree. The proxies for the MWP clearly sets a minimum standard. Perhaps even if it stays at the current temperature in a couple of hundred years, our worldit will look much closer to the world of the MWP. I would suggest that since we just rose from the LIA the warmth is not currently significant because it has not been around long enough to be something of great enough endurance to have confidence it will show up in a proxy a thousand years from now as does the MWP. What I see is in just the ocean oscillation record a rather clear pattern of about .7degC from natural variation (and I don't care if you use the recent one or the one at the beginning of the 20th century!). I don't see that pattern in the proxies and the reason might be that they are not sensitive enough to capture less than 100 year averages. Thats pretty significant because after that what left? About a half degree of modern warming? [/quote] Icefisher, If the current warming was not in line with expectations, and in line with predictions that have been on the table for many decades, then you may have a point. But it is, so you don't.
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Post by steve on Apr 27, 2013 12:56:46 GMT
I think the "few breeding pairs" was James Lovelock - who is "visionary" where "visionary" means sometimes delusional.
Clearly the UK experienced significant warming in the 80s and 90s. But only part of this could be explained by the average global warming trend.
This had two effects. 1) people in the UK felt they were experiencing global warming. 2) people in the UK were more likely to believe the temperature record because the temperature change was noticeable.
As only part of the warming was due to "global warming" (ie the average trend) there was scope for some reversal.
That said 2011-12 was one of those very warm winters that one remembers because of there being virtually no frost (till the SSW towards the end of winter). Ditto 2004-5 (I'd guess that was even warmer).
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Post by steve on Apr 27, 2013 12:41:29 GMT
As is usual with my maths, it's very "back of the envelop" so happy to revise based on comments.
Question: Does all the energy from the infrared radiation of the atmosphere at the sea surface go into evaporating water?
If it does:
Latent heat of evaporation of water 2260 J/g 1mm of water over 1m^2 equates to 1kg of water. Therefore 300W/m^2 "back radiation" would evaporate 1kg of water per 7500 seconds.
However, average rainfall per year is around 1 metre or 1000mm
If back radiation all goes into evaporating water, it would take 7.5 million seconds to evaporate this amount of water.
This is only 86 days - or 130 days taking into account the ocean is 2/3 of the planet.
Conclusion - there is not enough rainfall if back radiation only evaporates water.
Secondary conclusion, therefore some of the energy from back radiation *must* remain in the water for at least some time allowing it to be conducted or mixed into the deeper layers of the ocean.
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Post by steve on Apr 27, 2013 12:34:02 GMT
Be careful what you wish for. If the ocean has not yet warmed in response to the atmosphere warming, then there is a lot more atmosphere warming to come when the ocean catches up. But you haven't said whether you believe a warmer atmosphere will result in the ocean getting warmer due to causes other than the "penetrative power" (whatever that means) of the LW. Which bands? And by how much (in Watts, not percentage)? I think the ones that vary are the ones that don't penetrate the atmosphere much. So something you can't measure should be considered whereas something you can should not? Hmmm...sounds like argumentum ad backsidecovering Certainly better. But the XBT measurements show lower OHC even when you account for their relative shortcomings. You also have not explained the acceleration of sea level rise which backs up the OHC rise. 1. The ocean will not warm 'in response to atmospheric warming' the only thing that heats the ocean is shortwave radiation from the Sun - you admitted this yourself Steve. If you look at my last couple of posts I list a few processes whereby a warmer atmosphere could transfer heat to a colder ocean surface. A warmer atmosphere does *not* necessarily have a lower partial pressure for water vapour. You seriously cannot claim that. I have spent a whole *day* trying to dry washing in temperatures of over 30C and the washing was probably damper at the end of the day (not in England, mind you). If the atmosphere is warmed, then there is a one-off reduction in partial pressure and therefore a one-off reduction in ocean heat content as the ocean evaporates to rebalance the humidity levels. Therefore if the atmosphere retains its temperature (due to the energy imbalance caused by excess greenhouse gases) you will end up with a warm atmosphere and, essentially, the same partial pressure for water vapour. That is too hand wavey for me. How much has UV changed? In what way does 5W of UV warm the oceans more than 5W of yellow light? Yes, we know the climate varies naturally in many different ways. Interesting you put "corrections" in quotes. Have a look at how the albedo was calculated in your previous link! All sorts of corrections and assumptions there. That aside, your sentence doesn't make sense. Who has "claimed" a higher rise than, say, the "'corrected'" Levitus data that is quite prominent on the web? Unless the wind is moist - see previous comment. How much water vapour will be evaporated? Bored now - I'm going to do a bit of maths...
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