On Tue, 19 Aug 2008 07:33:14 -0700 (PDT), David
wrote:

On Aug 18, 5:47*pm, Eric Stevens wrote:
...
All this at a time when even NASA (read Hansen) is being forced to
re-evaluate downwards its estimates of temperature rise over the last
century. It is futile to try to reach conclusions from correllations
(or lack thereof) with a curve which has not yet been established with
a reasonable degree of confidence.
...

I say the Smith and Reynolds analysis has already established
the curve with a reasonable degree of confidence -

Brett Anderson - Accuweather
http://global-warming.accuweather.co...temperatu.html

"Keep in mind, the Smith and Reynolds analysis
takes into account record that go back 128 years."


Over which period urban heat islands have grown to swallow the sites
of weather stations; buildings have grown up around the weather
stations to shield them from the wind etc.

Its only in the last 10 years that serious corrections have started to
be made for these effects and the historical data has had to be
significantly amended. See the comments to the article in the URL you
have cited in which e.g. the effect of omitting Siberia from the data
is discussed.

Then there is
http://icecap.us/index.php/go/joes-b..._the_serious_d
which includes the graph at
http://icecap.us/images/uploads/ipccchart.jpg which demonstrates the
divergence between climate models and actual temperature. I've
actually seen better and longer term analysis than this but that's not
really relevant. My point is that we cannot determine whether or not
the climate is significantly warming or not while there is still so
much uncertainty about the historical record.



Eric Stevens