On Apr 12, 7:47*am, Falcon wrote:
In article , Tom P wrote...
On 04/12/2011 01:39 AM, Roger Coppock wrote:
The satellite record, in all its current interpretations, shows that
the air near the surface is warming. For background on the satellite
temperature proxy please see:
http://en.wikipedia.org/wiki/Satelli...e_measurements
The URL below is one of the more conservative records from the
University of Alabama at Huntsville.
http://vortex.nsstc.uah.edu/public/m...tglhmam_5.4The global
data are graphed hehttp://members.cox.net/rcoppock/UAH-MSU.jpg
The Remote Sensing Systems Lower Troposphere (TLT) analysis also shows
a temperature rise above the surface of the land and sea.
http://www.remss.com/data/msu/monthl...nthly_MSU_AMSU
_Channel_TLT_Anomalies_Land_and_Ocean_v03_3.txt The data from 82.5N to
70S are graphed hehttp://members.cox.net/rcoppock/RSS-MSU.jpg
The trend is very much dependent on the latitude. If you look at the
figures for the various latitude bands, the positive trend is most
dramatic for 60/82, and nearly as strong for -20/20, whereas the trend
for -70/70 is almost zero - which seems to indicate that temperate
latitudes are not warming??
It's also time-dependent. Roger's not the only one who can draw pretty
graphs, but in this example http://i55.tinypic.com/iwrg35.png you can see
how useful a linear trend line is, depending on what you want to show.
Any and all linear tend lines are useless without at the very least
some information on the reliability of the slope calculated. No
confidence interval = no value.
Also the residuals need to be calculated to ensure that original data
are homoscedastic, or again the result is questionable.
The
data is from Roger's thoughtfully provided source. I added another trend
line that's probably a little more representative of what's been happening
lately.
By taking a shorter time line, significance of any trend will be
lowered. It seems certain that the weak down-turn your graph shows
results from random fluctuations rather than any real change in the
rate of warming.
snip