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Bunter
User Rank
Platinum
RE: Needs
Bunter   10/2/2013 5:13:54 PM
NO RATINGS
Oh, just one more quicky Ted.  Antarctic ice has been expanding over the past few decades.

And this year, which some had predicted a few years ago would see an ice free arctic has seen ice expansion.

Have seen arguements the reduction in recent years was due to chages in ocean current (those guys again) rather than the feeble surface warming.

Just a thought.

TTFN

Dennis

trees
User Rank
Iron
RE: Needs
trees   10/9/2013 2:57:51 AM
NO RATINGS
Dennis,

 My understanding of the ice ages, is that they are caused by the Milankovitch cycles of the earth orbit. When it is an ice age, the northern hemisphere is tilted away from the sun at the same time the earth is closest to the sun in the ellipiical orbit. Naturally then, the southern hemisphere is pointed toward the sun at that time. The ice age is a time of a warm southern hemisphere, and a cold northern hemisphere. Likewise, between ice ages, the opposite is true. A warm northern hemisphere coincides with a cold southern hemisphere.

   But, global warming, affects the whole planet. So why the increase in southern sea ice?  .... The story I've read is that the antarctic ice shelf (not sea ice), has melted, and cold water has resulted, which allows the antarctic sea ice to expand. Also, that the loss of ice up north exceeds the gain of ice down south. 

    As for predictions, I think the plot of arctic sea ice vs. time is sufficient evidence of where it has been and where it is going. Of course hind site is always more accurate than prediction. 

 

ted

trees
User Rank
Iron
RE: Needs
trees   10/9/2013 3:46:06 AM
NO RATINGS
Dennis,  

  Thanks for your continued civil reply.

  I saw a good argument on your side about surface temperature. I don't remember the site, but something about Watts up?  Anyway, it pointed out that the surface temperature record was suspect because so many thermometers were located in urban areas that have been shown to be heating up.

   Next, if the earth were entirely dirt, (no ice or water), the average surface temperature would track the net forcing quite quickly because dirt does not easily conduct heat down into great depths. A few feet of dirt would be heated probably within a year.  Given that assertion, we would only expect 0.4C increase in average surface temperature for 1.6W/m.sq. Any added temperature increase would have to come from 'amplification'. We would expect the temperature to be proportional to the forcing over these small forcings.  Given the noise in the data, the current 'stabilization' of surface air temperatures at 0.8C rise doesn't bother me. Ocean temperatures have not been measured enough yet to indicate anything.  Again, ice melt seems to be the best indicator of warming. 

   I don't have anything to say about politics, other than that it sucks. 

   The IPCC says with 95% confidence that warming is real, and man made. We know that means a bit more solar absorption than heat radiation output, for whatever reason. If not greenhouse gas, then what? 

  Of course during the ice ages, the temperature changes first, then the CO2. The driving forcing is the earth orbit change. During heating, the CO2 quickly follows. During cooling, the CO2 lags up t 10000 years. That inability of the earth to absorb the excess CO2 is scary!

   Right, we will not settle the science of CO2 as a greenhouse gas easily. There are nice graphs of spectral absorption in space. But, we need nice graphs of differences of spectral absorption in space vs. changes in CO2 concentration. ... hmmm, I think thay have that.   http:// www.youtube.com/watch ?    v=FqDBcoTSd1M 

  The CO2 concentration is not uniform, and the satalites can see it. How? I suspect by sending laser beams from space into the atmosphere and measuring the reflections at the CO2 wavelengths. ...

  But, that is not the same as measuring a difference in output radiation through the CO2. 

   Or we need theory that is beyond the scope of this discussion. 

   Final conclusion?  I still suspect excess fossil fuel CO2 causing warming, on a very slow time scale, but with an enormous inertia. Sooner or later fossil fuels extraction will require as much energy to extract as is obtained from the fuel. That will be the end of fossil fuels for energy use. Fossil fuels are used for a lot of other purposes.  Moving long distance travel to renewable energy is very difficult. But most other energy uses seem simple enough to change to renewable.  If we think long term, we should be trying to preserve the planet for future generations. We don't seem to be doing that. 

 

  On your side?  I suspect it is don't worry. Don't let the government interfere with free enterprise. 

 

ted

   

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