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Post by glc on Jun 9, 2010 7:53:19 GMT
So the trend over the period 2002 - 2007 is biased downwards by shortterm ENSO and solar cycles. So imo the "flatness" does not support the idea that the warming has ended. Indeed! And the 1980 to 2001 trend was biased upwards by short term ENSO and solar cycles. Nicely in line with Akasofu and Easterbrook. But the 2008 La Nina year was warmer than every year before 1998. I'm afraid it's the short-termism with the timing of the ENSO events which creates the downward trend. We all remember how the UAH record showed cooling since 1998 - well it ain't now. Incidentally, Easterbrook's projections don't seem to working out too well.
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Post by icefisher on Jun 9, 2010 15:53:20 GMT
Indeed! And the 1980 to 2001 trend was biased upwards by short term ENSO and solar cycles. Nicely in line with Akasofu and Easterbrook. But the 2008 La Nina year was warmer than every year before 1998. I'm afraid it's the short-termism with the timing of the ENSO events which creates the downward trend. We all remember how the UAH record showed cooling since 1998 - well it ain't now. Incidentally, Easterbrook's projections don't seem to working out too well. I suppose you could quantify that in comparison with the IPCC right? When you say didn't work out too well that is a relative term. So you need to put it in context with some well known projection or your statement is vacuous. To put in some context the IPCC predicted a trend in excess of the long term warming trend and Easterbrook predicted it would be less of a trend, maybe a cooling trend as his projections show an oscillation about the longterm trend on a rather regular schedule whereas the IPCC predicted the longterm oscillations were now passe and forcing had overridden natural variation which has been an unsupportable position now for 15 years and counting yet continued to be the IPCC position as its advocates have bumbled around looking for missing heat and not finding it.
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Post by twawki on Jun 23, 2010 10:22:26 GMT
Why does everything the government wants to do seems to be to hasten the cooling that natural cycles say could be devastating www.twawki.com/?p=7075
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Post by nautonnier on Jun 23, 2010 18:04:46 GMT
Why does everything the government wants to do seems to be to hasten the cooling that natural cycles say could be devastating www.twawki.com/?p=7075Contrails only exist because the atmosphere at the level the aircraft is flying is close to, or is actually, saturated with water vapor. Then the water in the engine eflux condenses out into water droplets and then into ice crystals as it cools. The contrails will only be there if the air is already saturated with water vapor. An analogy is footprints in snow can only be there if there is snow. If the atmosphere is totally saturated by water vapor then the contrails will remain and be persistent slowly being smeared out by windshear if there is any. If the atmosphere is not fully saturated then the contrail will slowly disappear as the water droplets slowly evaporate back. If there is a standing wave in the wind with a layer of saturated air - then contrails may appear as dashed lines where the aircraft clips through the saturated air in the wave in the atmosphere. If the air is saturated then there may be a heating effect at that level in the atmosphere as the water vapor - as the most effective greenhouse gas - absorbs outgoing IR leading to convection. If persistent contrails form then the water droplets or ice crystals will raise albedo and reflect away incoming solar radiation reducing heat content below the contrails. In almost all cases over land the number and routes of aircraft are the same day to day. Nowadays there are more direct routes flown so they may not always follow the same paths. So if you have a day without contrails - the upper atmosphere is dry, if you see intermittent non-persistent contrails there is some humidity, and if you see continual persistent contrails turning into solid cirro-stratus then water vapor is saturating the atmosphere at that level. The humidity at height and the affect this has on atmospheric heat content is almost always disregarded by people making simplistic temperature measurements.
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Post by twawki on Jun 23, 2010 22:28:19 GMT
Thanks Naut.. much appreciated - good to know
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Post by walterdnes on Jun 26, 2010 3:55:01 GMT
Contrails only exist because the atmosphere at the level the aircraft is flying is close to, or is actually, saturated with water vapor. Then the water in the engine eflux condenses out into water droplets and then into ice crystals as it cools. The contrails will only be there if the air is already saturated with water vapor. An analogy is footprints in snow can only be there if there is snow. I don't mean to be argumentative, but that answer is very misleading, even if it's sorta right. The root cause of contrails is that at really cold temperatues the water-holding capacity of the atmosphere is very low. E.g. around minus 40 C, the water-holding capacity of the atmosphere is approx 2% of what it is at zero C, Dumping almost any amount of water vapour into the atmosphere at -40 C causes contrails. Large commercial passenger jets cruise at altitudes where temperatures are that cold (30,000 plus feet). I can guarantee you that at plus 30 C (approx 86 on the Fahrenheit scale), a jet belching tonnes of exhaust taking off from Miami Florida airport will *NOT* cause a condensation, even on a muggy day. At the opposite extreme, a dinky single-engine, propellor-driven bush plane at an air strip in northern Canada on a cold winter day (-35 or -40 C) can sock in the place for an hour or two after taking off, even if the relative humidity was 10% just before the takeoff.
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Post by nautonnier on Jun 26, 2010 5:33:29 GMT
Contrails only exist because the atmosphere at the level the aircraft is flying is close to, or is actually, saturated with water vapor. Then the water in the engine eflux condenses out into water droplets and then into ice crystals as it cools. The contrails will only be there if the air is already saturated with water vapor. An analogy is footprints in snow can only be there if there is snow. I don't mean to be argumentative, but that answer is very misleading, even if it's sorta right. The root cause of contrails is that at really cold temperatues the water-holding capacity of the atmosphere is very low. E.g. around minus 40 C, the water-holding capacity of the atmosphere is approx 2% of what it is at zero C, Dumping almost any amount of water vapour into the atmosphere at -40 C causes contrails. Large commercial passenger jets cruise at altitudes where temperatures are that cold (30,000 plus feet). I can guarantee you that at plus 30 C (approx 86 on the Fahrenheit scale), a jet belching tonnes of exhaust taking off from Miami Florida airport will *NOT* cause a condensation, even on a muggy day. At the opposite extreme, a dinky single-engine, propellor-driven bush plane at an air strip in northern Canada on a cold winter day (-35 or -40 C) can sock in the place for an hour or two after taking off, even if the relative humidity was 10% just before the takeoff. Aircraft are flying ALL the time overhead contrails will only appear if when the exhaust gas which is at ~600C cools the air is too saturated for the water in that exhaust to remain as water vapor. That is why there are days when there are NO contrails days when there are persistent contrails and days when there are non-persistent contrails - this is observable on most days. So now go to here www.nextor.org/project1.php_files/FACETmovie.wmvThis is a movie file made from recordings of aircraft position reports from the air traffic control center systems (called Aircraft Situation Display to Industry) over North America using an analysis tool FACET developed by NASA. The traffic is close to identical most week days with some peaks like the Wednesday before Thanksgiving. Now go to www.intelliweather.com/popup/nat_sat_popup.htmIntelliweather GOES satellite imagery to show clouds. There should be permanent solid cirrus cloud cover from contrails over the East coast given the amount of traffic - but there is not. Most days when you look into the clear blue sky there are no contrails but there are still aircraft there. There are aircraft overhead Philadelphia ALL the time - but Philadelphia still gets clear blue sky days. Contrails only form when the surrounding air's mixing ratio is so high that the water in the jet efflux condenses out as the jet efflux cools. Just some more references with perhaps more authority... Encyclopædia Britannica article on vapour trails (contrails):Contrail, streamer of cloud sometimes observed behind an airplane flying in clear, cold, humid air. It forms upon condensation of the water vapour produced by the combustion of fuel in the airplane engines. When the ambient relative humidity is high, the resulting ice-crystal plume may last for several hours. The trail may be distorted by the winds, and sometimes it spreads outwards to form a layer of cirrus cloud. vapour trail. (2007). In Encyclopædia Britannica.Retrieved May 4, 2007,from Encyclopædia Britannica Online: www.britannica.com/eb/article-9074829Journal of Climate 2003; 16: 3447-3462 Contrail Frequency over the United States from Surface Observations
Abstract Contrails have the potential for affecting climate because they impact the radiation budget and the vertical distribution of moisture. Estimating the effect requires additional knowledge about the temporal and spatial variations of contrails. The mean hourly, monthly, and annual frequencies of daytime contrail occurrence are estimated using 2 yr of observations from surface observers at military installations scattered over the continental United States. During both years, persistent contrails are most prevalent in the winter and early spring and are seen least often during the summer. They co-occur with cirrus clouds 85% of the time. The annual mean persistent contrail frequencies in unobscured skies dropped from 0.152 during 1993–94 to 0.124 in 1998–99 despite a rise in air traffic. Mean hourly contrail frequencies reflect the pattern of commercial air traffic, with a rapid increase from sunrise to midmorning followed by a very gradual decrease during the remaining daylight hours. Although highly correlated with air traffic fuel use, contrail occurrence is governed by meteorological conditions. It is negatively and positively correlated with the monthly mean 300-hPa temperature and 300-hPa relative humidity, respectively, from the National Centers for Environmental Prediction (NCEP) reanalyses. A simple empirical model employing the fuel use and the monthly mean 300-hPa temperatures and relative humidities yields a reasonable representation of the seasonal variation in contrail frequency. The interannual drop in contrail frequency coincides with a decrease in mean 300-hPa relative humidities from 45.8% during the first period to 38.2% in 1998–99, one of the driest periods in the NCEP record.journals.ametsoc.org/doi/abs/10.1175/1520-0442(2003)016<3447:CFOTUS>2.0.CO;2Note from the last reference that contrails co-occur with cirrus clouds 85% of the time - this is to be expected as the presence of cirrus shows that the atmosphere is saturated. Another thing to note of interest is the way the atmosphere had " one of the driest periods in the NCEP record" in 1998/9 - what happened at that time??? Hmmmm El Nino Dry air has less enthalpy so will increase in temperature faster for a given heat content - there were record temperatures in 1998/9 What happened 2009-10 and why have we got record temperatures now? Hmmmm _another El Nino. Could low enthalpy have something to do with the record 'temperatures'?
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Post by twawki on Jul 5, 2010 6:06:35 GMT
Is it possible those in positions of power were aware that global cooling was coming? There was the ice age scare and then it was dropped. Then the temps were artificially inflated to create a warming that really was originally not abnormal. As each week goes on with the inactive sun the more worrying this gets!
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Post by stranger on Jul 6, 2010 1:49:59 GMT
Twawki, the answer to your last question is a qualified yes. Yes, it is probable, not merely possible.
All of the scientific research indicated another ice age, or at least a "Little Ice Age," was upon us.
Then things got really quiet.
And all of a sudden the seas were going to boil next Tuesday unless we stop generating electricity, driving cars, cooking food, and so on and so forth.
That particular pattern is a very old one. Usually associated with deliberate scams of one sort or another.
The drivers seem to be a group who want to reduce the Earth's population to "the carrying capacity of the Earth," much as a rancher may adjust the number of cattle he grazes on leased land. But in this case, the postulated carrying capacity is around 250 million - and we have almost 7 thousand million humans.
While "we will never get out of this world alive," I would prefer to leave it by conventional means.
Stranger
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Post by julianb on Jul 6, 2010 10:19:55 GMT
Twawki Have a look at this, out of their own mouths,
"The common enemy of humanity is man. In searching for a new enemy to unite us, we came up with the idea that pollution, the threat of global warming, water shortages, famine and the like would fit the bill. All these dangers are caused by human intervention, and it is only through changed attitudes and behavior that they can be overcome. The real enemy then, is humanity itself." - Club of Rome, premier environmental think-tank, consultants to the United Nations
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"We need to get some broad based support, to capture the public's imagination... So we have to offer up scary scenarios, make simplified, dramatic statements and make little mention of any doubts... Each of us has to decide what the right balance is between being effective and being honest." - Prof. Stephen Schneider, Stanford Professor of Climatology, lead author of many IPCC reports
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"We've got to ride this global warming issue. Even if the theory of global warming is wrong, we will be doing the right thing in terms of economic and environmental policy." - Timothy Wirth, President of the UN Foundation
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"No matter if the science of global warming is all phony... climate change provides the greatest opportunity to bring about justice and equality in the world." - Christine Stewart, former Canadian Minister of the Environment
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“The data doesn't matter. We're not basing our recommendations on the data. We're basing them on the climate models.” - Prof. Chris Folland, Hadley Centre for Climate Prediction and Research
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Post by julianb on Jul 6, 2010 10:22:36 GMT
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Post by socold on Jul 6, 2010 15:11:06 GMT
Curious omission added in bold:
"We need to get some broad based support, to capture the public's imagination... So we have to offer up scary scenarios, make simplified, dramatic statements and make little mention of any doubts... Each of us has to decide what the right balance is between being effective and being honest. I hope that means being both - Prof. Stephen Schneider, Stanford Professor of Climatology, lead author of many IPCC reports
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Post by icefisher on Jul 6, 2010 17:27:18 GMT
Curious omission added in bold: "We need to get some broad based support, to capture the public's imagination... So we have to offer up scary scenarios, make simplified, dramatic statements and make little mention of any doubts... Each of us has to decide what the right balance is between being effective and being honest. I hope that means being both- Prof. Stephen Schneider, Stanford Professor of Climatology, lead author of many IPCC reports Doesn't add anything. Its a curious discussion with or without the addition. Like its "I hope" not "It has to be both". And the essential drift of the entire comment runs contrary to UEA's Mike Hulme talking about being more upfront and transparent about uncertainties. Here it is about shading the truth to make it appear as certain as possible. Hulme's comment runs absolutely the opposite direction Schneider has been pushing it. Schneider should drummed out. As long as he is anywhere near any of this stuff it will be hopeless rebuilding any public confidence.
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Post by socold on Jul 6, 2010 20:24:55 GMT
Schneider is correct though, education (giving it) is a balance between honesty and effectiveness. While you may hope to be both, you often cannot.
Would you tell an 8 year old kid that the Earth is round like a ball or that the earth is an oblate spheroid? The former is wrong. The latter is more correct, although even not 100% true.
It wouldn't be effective to tell an 8 year old the honest truth in this case. Telling them it's round like a ball is the more effective.
And then there's the whole "how many days in a year?" question. Telling someone it's "365" keeps it simple and might be the most effective way of educating them if they aren't ready to understand leap years. Even leap years aren't the end of the story given the average is not exactly 365.25 days, but closer to 365.24 (and then of course that number probably isn't even constant over millions of years)
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Post by poitsplace on Jul 6, 2010 20:44:36 GMT
And telling that 8 year old horror stories about CO2 is about the same as telling him that demons are going to come get him if he's bad. That's WAY different than the .1% error (or less) you find in the "365 days = 1 year" or the "earth is a ball" generalization.
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