Uh, perhaps. I'm fairly convinced about ozone depletion because we
can see precisely what's going on in the atmosphere; but in this case
all we have are old measurements which may not be very accurate.
> some scientists are not
> yet convinced that the atmosphere is also warming. but as the figure
> shows, the 1979-95 data series may be too short to show the trend.
Unfortunately they don't show the figure. They do show another figure
on another page which claims the surface increased in temperature by
0.6F in that time, which rather seems to contradict the atmospheric
data.
> Thus, even the surface temperature measurements--which show a
> steady warming trend over the last century--do not show much of a warming
> trend when one only considers data since 1979.
Uh, their own graphs show 0.6F increase at the surface since 1979. See
http://www.epa.gov/globalwarming/climate/index.html.
> Balloon data, which shows
> the same absence of warming over the 1979-95 period shows a significant
> warming trend from 1958 to 1993.
Their own graphs show a large temperature peak around 1941; on this
basis we could imply that 1958 was a particularly cold year, and hence
the warming is merely a coincidence. And I'm still puzzled as to how
the same set of data could show warming from 1958-1993 but cooling from
1979-1995; if it was only a few years, perhaps, but 1979 is close to
the midpoint of that range.
> Measurement errors associated with the
> new technology, and cyclical variations in temperature due to El Ninos,
Variations accounted for, errors checked against balloon measurements.
Hal added:
>We know that two decades is not really enough to expect to see a clear
>trend, and apparently it happened that the beginning of the interval was
>unusually warm, swamping the trend.
But that would imply that natural processes in the atmosphere can
swamp artificial changes, and hence global warming is a non-issue
anyway.
>Expanding the time frame as shown
>by the balloon measurements does appear to confirm the warming trend.
Did you find a source for those? They just state it and don't provide
a link. I'll check the NASA site.
Mark