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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 |
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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 |
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