On 25/06/18 11:31, Alastair wrote:
On Monday, 25 June 2018 10:42:03 UTC+1, Graham P Davis wrote:

If you look at the graph in the following section, you'll see the
extrapolated curve reaches near +1.7C by 2040. As this anomaly is based
on my own estimate of the mean temperature for the pre-industrial era
rather than the rather dubious Met Office figure, that equates to +1.5C
using their baseline.
http://www.scarlet-jade.com/science/...ange/#analysis


Graham,

What is the Met Office/IPCC base line?

Is it described anywhere?

Cheers, Alastair.


They use 1850-1900 as that's the earliest period for which they have
data but that's after the start of the industrial era so would have
already experienced warming from increased CO2.

In 1850, CO2 was about 285 and rose to 296 by 1900. So the Met Office /
IPCC pre-industrial period had CO2 levels 5-16ppm above the level
accepted as being representative of the pre-industrial era (280ppm).

I've described my reasons for not using the Met Office / IPCC baseline
in the "latest data" section below the above link. I probably should
have placed it in the previous section.

--
Graham P Davis, Bracknell, Berks. Web-site: http://www.scarlet-jade.com/
"There is nothing more frustrating than playing hide and seek with a
deaf wolf." [Benton Fraser]
OS: Linux [openSUSE Tumbleweed]