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Clive Mitchell
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Some bright guy once said that repeatedly doing the same thing and expecting different results was stupid. Scientists have been telling the world for years that, with a lot of effort, 2 deg. C is avoidable. A lot of effort consistently has not been "with-ed" for years so it looks like 2C is not going to be avoided. To deny that is looking like false hope and wishful thinking. Perhaps we need to stop being stupid and do something different. Billions of people dying is not important. It's just statistics and (probably/possibly/maybe) "not here". (Until it kicks your door in.) What is important is politicians losing their place in history. Perhaps the new message from science should be, "The recent socio-political record shows that we will not avoid 2C. Arctic sea ice loss will affect the jet stream in x years sufficiently to disrupt harvests by y% leading to global food shortages and riots in cities" (with recent examples of food riots) "resulting in the progressive collapse of civilization. The survivors' struggles will not include trying to retain the political history of the world. Your legacy will be forgotten." It may get a different result. Worth a try?
Toggle Commented May 16, 2015 on Bill McKibben nails it at Arctic Sea Ice
I think the trouble with the animation is the light appears to be coming from the bottom right. Turn your head (or the monitor) upside-down to see normal shadows for the end of the glacier.
Chris, you appear to be assuming that the only source of heat available to melt the GIS in situ is direct solar radiation. An ice-free ocean should produce more water vapor to transfer heat to the ice sheet by condensation. Also, the lack of sea ice to melt and cool incoming surface waters may permit heat from the Atlantic and Pacific to be available to assist evaporation.
Toggle Commented Mar 21, 2014 on PIOMAS March 2014 at Arctic Sea Ice
Sorry for repeating myself but as this is a complex system with tipping points, I suspect that looking for a change in trend in a rolling average is a reasonable approach. For example, a five-year rolling average of the volume minima from 1984 (starting 1979) to 2013 reveals an apparent instability up to 1988, then a linear trend to 2005 followed by a sharper linear trend to the present extrapolating to zero at around 2019. It is a two-minute job to plot this. Unfortunately, I do not have the wherewithal to determine closeness of fit, nor to upload the chart. If you have a spare few minutes, your comments would be most welcome.
Toggle Commented Nov 10, 2013 on PIOMAS October 2013, take two at Arctic Sea Ice
Thanks, Chris. Interesting papers. I'm not sure about sea ice chasing down to a lower equilibrium. If excess heat inflow is consistently available at a temperature which will melt sea ice, sea ice will melt until sea ice is all gone - the melting point of ice is not a continuous variable to be adjusted for equilibrium purposes. The new equilibrium will be reached when the heat inflow and outflow balance and I fear this will involve a temperature which is too high to sustain sea ice. On a global scale, less heat is being employed raising temperature and more heat is being employed melting ice, but as you imply, there are a great deal of other mechanisms.
Toggle Commented Sep 28, 2013 on Pinpointing the minimum at Arctic Sea Ice
Further to my former post, I found some data, thanks. In a four or five year rolling average plot of surface temperature change superimposed with rolling average September Arctic ice volume against time, the ice volume appears to decrease at a steady rate then shows a distinct change to a new steady rate, the change corresponding to the flattening in the temperature curve. Of course, I'm an amateur and this could be bunkum but if the surface temperature rose until the late '90s when a resultant small increase in the rate of ice melt was sufficient to absorb all the heat formerly going into surface temperature increase, what sort of temperature rise can we expect when the ice melt rate levels out? Let's hope it's just amateur bunkum!
Toggle Commented Sep 26, 2013 on Pinpointing the minimum at Arctic Sea Ice
Sorry for being off-topic but with the IPCC/temperature increase hiatus debate, does anyone have the wherewithal to plot flattening temperature rolling average and ice volume minimum rolling average on the same graph, crossing over around 1998, please? Or let me know where I can find the data? Thanks
Toggle Commented Sep 26, 2013 on Pinpointing the minimum at Arctic Sea Ice
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Sep 23, 2013