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#261
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Global Warming/Climate Change (was contrails)
Being a bit touchy aren't we Tom? If you want to present AGW/Climate Change as a religion (which it seems to have become), then I am neither a believer or a disbeliever (denialist), but an agnostic. The latest data on World temperatures, which show a slight cooling, do not correlate with the theory, so that is why. Not according to people who actually track that sort of thing: http://www.ncdc.noaa.gov/sotc/?report=global#gtemp Possibly you were thinking of data sets that begin with the El Nino event of 1998-99? If you use that as your starting point then it biases the result to show fairly flat temperatures from 1998 - 2008, just like you could use it to exaggerate increasing temperatures from 1989 1999. I think some people call that 'cherry picking' the data. For myself, I don't put much stock in the currently available database of direct temperature measurements, and less stock in proxies. In both cases the sampling problem looms large. I do trust the measurements of atmospheric gases from Mauna Loa and the measurements of solar activity. Those are much easier to sample. If one does accept direct temperature measurement and pre-Mauna Loa atmospheric gas measurements and proxies like these: http://en.wikipedia.org/wiki/File:In...ure_Record.png What we see is a temperature rise of ~ 0.7 degrees Celsius during the 20th century. One can explain that as follows: Temperatures rose quickly at the end of the 19th century due to methane released by oil exploitation (early on there was no market for natural gas so gas wells were typically left uncapped). As methane has a fairly low half life in the atmosphere (12 years) temperatures dropped quickly until 1910 or so at which point carbon emissions from industrial growth caused a continuous rise through WWII. Then very rapid industrial growth and coal burning in particular, especially to power the world's electrical grids loaded the atmosphere with aerosols that offset the increased greenhouse effect of the concurrently released carbon dioxide until pollution abatement came into vogue in the 1970s. This pollution abatement concentrated on particulates and sulfur compounds, but ignored carbon dioxide. As particulates continued to drop out of the atmosphere and carbon-dioxide rose so did temperatures from then until now, with a noted acceleration after German reunification produced a cleanup of East German Industry. Other explanations are possible. -- FF |
#262
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Global Warming/Climate Change (was contrails)
On 24 Jan, 00:25, Fred the Red Shirt wrote:
Being a bit touchy aren't we Tom? If you want to present AGW/Climate Change as a religion (which it seems to have become), then I am neither a believer or a disbeliever (denialist), but an agnostic. The latest data on World temperatures, which show a slight cooling, do not correlate with the theory, so that is why. Not according to people who actually track that sort of thing: http://www.ncdc.noaa.gov/sotc/?report=global#gtemp Possibly you were thinking of data sets that begin with the El Nino event of 1998-99? If you use that as your starting point then it biases the result to show fairly flat temperatures from 1998 - 2008, just like you could use it to exaggerate increasing temperatures from 1989 1999. I think some people call that 'cherry picking' the data. For myself, I don't put much stock in the currently available database of direct temperature measurements, and less stock in proxies. *In both cases the sampling problem looms large. I do trust the measurements of atmospheric gases from Mauna Loa and the measurements of solar activity. *Those are much easier to sample. If one does accept direct temperature measurement and pre-Mauna Loa atmospheric gas measurements and proxies like these: http://en.wikipedia.org/wiki/File:In...ure_Record.png What we see is a temperature rise of ~ 0.7 degrees Celsius during the 20th century. One can explain that as follows: Temperatures rose quickly at the end of the 19th century due to methane released by oil exploitation (early on there was no market for natural gas so gas wells were typically left uncapped). As methane has a fairly low half life in the atmosphere (12 years) temperatures *dropped quickly until 1910 or so at which point carbon emissions from industrial growth caused a continuous rise through WWII. Then very rapid industrial growth and coal burning in particular, especially to power the world's electrical grids loaded the atmosphere with aerosols that offset the increased greenhouse effect of the concurrently released carbon dioxide until pollution abatement came into vogue in the 1970s. This pollution abatement concentrated on particulates and sulfur compounds, but ignored carbon dioxide. As particulates continued to drop out of the atmosphere and carbon-dioxide rose so did temperatures from then until now, with a noted acceleration after German reunification produced a cleanup of East German Industry. Other explanations are possible. -- Climate change has always happened through perfectly natural events. Such as: 1) Changes in the Earth's orbit. 2) Changes in the Sun's activity levels. 3) Volcanic eruptions. 4) Large meteorite strikes. Should we get the East Germans to start producing smoky two-stroke Trabant cars in factories powered by smoky coal fired power stations again, to reverse global warming? That seems to be one of your arguments. Remember also that there was a large meteorite strike in Siberia in 1908, which might have caused a cooling event, followed by a slow rise in temperatures again. Also the Mount St Helens volcanic eruption in 1980 put loads of particulates into the atmosphere. I remember that we had a pretty awful cold wet summer after that. Derek Copeland |
#263
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contrails
Tom Gardner wrote:
.... On the micro-climate scale, people round here are glad of a winter cold spell - to extinguish the noxious pests, if only temporarily. Brian W-... I was looking forward some nice Mediterranean type weather for the UK by now, due to global warming. In practice it seems to be colder wetter and snowier. What went wrong? Derek Copeland .... I was shocked when somebody showed me that the UK is approximately on Siberian latitudes, so that there is supposed to be some warm flow that keeps it bearable .... That would be the Gulf Stream. rj .... I don't argue with the naming of the warm Northward current, I argue with the idea that the climate is bearable! :-) Brian W ObJoke: we don't have climate, we have weather! ... the variability of which makes us acutely sensitive to changes. ... and is the reason why "the weather" is a standard conversation topic amongst the British Ha! You said it. B |
#264
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AGW/Climate Change (was contrails)
On 12 Feb, 01:23, brian whatcott wrote:
Tom Gardner wrote: On the micro-climate scale, people round here are glad of a winter cold spell - to extinguish the noxious pests, if only temporarily. Brian W-... I was looking forward some nice Mediterranean type weather for the UK by now, due to global warming. In practice it seems to be colder wetter and snowier. What went wrong? Derek Copeland ... I was shocked when somebody showed me that the UK is approximately on Siberian latitudes, so that there is supposed to be some warm flow that keeps it bearable ... That would be the Gulf Stream. rj ... I don't argue with the naming of the warm Northward current, I argue with the idea that the climate is bearable! *:-) Brian W ObJoke: we don't have climate, we have weather! ... the variability of which makes us acutely sensitive to changes. ... and is the reason why "the weather" is a standard conversation topic amongst the British Ha! You said it. B On another group an AGW/Climate Change believer claimed that the recently observed slight global cooling was a blip caused by an absence of sun spots and reduced solar output. In that case can we say for sure that the Sun wasn't just unusually active during the 20th century? Derek Copeland P.S. No sign of Mediterannean weather for the UK yet. We have had one of the coldest winters for many years! |
#265
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AGW/Climate Change (was contrails)
On Feb 12, 4:19*am, delboy wrote:
On 12 Feb, 01:23, brian whatcott wrote: Tom Gardner wrote: On the micro-climate scale, people round here are glad of a winter cold spell - to extinguish the noxious pests, if only temporarily. Brian W-... I was looking forward some nice Mediterranean type weather for the UK by now, due to global warming. In practice it seems to be colder wetter and snowier. What went wrong? Derek Copeland ... I was shocked when somebody showed me that the UK is approximately on Siberian latitudes, so that there is supposed to be some warm flow that keeps it bearable ... That would be the Gulf Stream. rj ... I don't argue with the naming of the warm Northward current, I argue with the idea that the climate is bearable! *:-) Brian W ObJoke: we don't have climate, we have weather! ... the variability of which makes us acutely sensitive to changes. ... and is the reason why "the weather" is a standard conversation topic amongst the British Ha! You said it. B On another group an AGW/Climate Change believer claimed that the recently observed slight global cooling was a blip caused by an absence of sun spots and reduced solar output. In that case can we say for sure that the Sun wasn't just unusually active during the 20th century? Derek Copeland P.S. No sign of Mediterannean weather for the UK yet. We have had one of the coldest winters for many years! There's some indication the extended solar minimum ended about December 12th. |
#266
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AGW/Climate Change (was contrails)
How much would the weather patterns change if the average earth temp
went up 2 degF? how many storms and droughts? how much alteration in ocean current? How many failed crops for dryland farmers? How much of this can we tolerate? The earth is perched in pretty fine ballance supporting 6+ billion H sapiens, and more all the time. How much room is left for the other forms of life on this planet? How hard would we have to hit the last undeveloped landmasses if there were widespread crop failures? How many starvations in the undeveloped world? How many would die of thrist on a planet where fresh water is already a thin commodity? How many extinctions of unique and wonderful species, let alone the possible commercial values of said species? How many dislocations and migrations of populations can we handle? (witness the slow remedy in Haiti for a relatively mild disaster on a world scale.) Are you so sure global warming is hoax? Are you willing to risk all of this on a stubborn point? If you are not concerned, you are not thinking. Mark Jardini MD, Capt, USAF (ret) |
#267
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AGW/Climate Change (was contrails)
On Feb 12, 1:08*pm, Mark Jardini wrote:
How much would the weather patterns change if the average earth temp went up 2 degF? how many storms and droughts? how much alteration in ocean current? How many failed crops for dryland farmers? How much of this can we tolerate? The earth is perched in pretty fine ballance supporting 6+ billion H sapiens, and more all the time. How much room is left for the other forms of life on this planet? How hard would we have to hit the last undeveloped landmasses if there were widespread crop failures? How many starvations in the undeveloped world? How many would die of thrist on a planet where fresh water is already a thin commodity? How many extinctions of unique and wonderful species, let alone the possible commercial values of said species? How many dislocations and migrations of populations can we handle? (witness the slow remedy in Haiti for a relatively mild disaster on a world scale.) Are you so sure global warming is hoax? Are you willing to risk all of this on a stubborn point? If you are not concerned, you are not thinking. Mark Jardini MD, Capt, USAF (ret) Enough of this global warming discussion on RAS. If you guys have so much time, go and join another group. This is about flying please be respectful. Do we really want to discuss politics here? I hope not. |
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