How to cherry-pick your 'Global warming has stopped' argument - in pictures
- 03 Feb 2012, 13:40
- Robin Webster
How many pictures does it take to tell a story? The publishers
of the Mail clearly appreciate that it doesn't take too many to get
your point over, and in recent months have fallen back with
increasing frequency on using the same few images to tell the same
story about climate science.
Despite repeated explanations from scientists that global
temperature data shows that the earth is warming, the
Mail and its
fellow travellers prefer to argue a different story - that
'global warming has stopped' over the last decade (or so).
Sometimes (for example in article in last week's
Mail on Sunday) this is extended to argue (
wrongly) that we are about to enter a '
mini ice age' as a result of declining sun spot activity. This
is illustrated by
a painting of the frozen Thames that the MoS like so much they
apparently own the copyright on it.
Scientific
papers in fact show that changes in the sun's activities are
not likely to offset the impact of rising carbon dioxide levels and
a "mini ice age" is
pretty unlikely in the near future, but the Mail don't let that
get in the way of their assertion that 'if NASA scientists are
right the Thames will be freezing over again.' (NASA
scientists have not suggested this, as far as we can tell.)
Then, in order to back up their misleading
statement that "the rising trend in world temperatures stopped in
1997/1998/2000" (take your pick), there is usually a graph that
looks a bit like this, showing global temperatures as assessed by
the Hadley Centre over the past 15 years or so:
It does look convincing, right? Another notable use of this
graph comes from skeptic think-tank the Global Warming Policy
Foundation, who feature a version of it as their website
banner.
But while this graph is featured - whether by the Mail or the
GWPF - there rarely seems to be space to include a graph with a
longer timeline on the x-axis.
Of course, this would tend to slightly undermine the argument
that 'global warming has stopped', if only by revealing that there
have been many other periods over the past century when temperature
rise has 'stopped' over short periods - depending on where you
start and finish your measurement. Look at the big picture, and the
long-term global temperature trend hasn't changed - it's still
rising.
But never mind. That's usually as much detail as the Mail or the
climate skeptic think tanks provide.
An article on the climate science blog Skeptical
Science has also suggested a couple of other useful graphics
that it wouldn't be entirely surprising to find in future articles
which declare that 'global warming has stopped'.
First, focusing exclusively on temperature rise obscures the issue
of where all the extra heat energy the planet is trapping is going.
The vast majority of it enters the oceans, which warm much more
slowly than the atmosphere. So if you want to avoid covering that
fact, try this graph:
This figure is taken from a data by
Church et al, 2011.
The same argument has been equally well illustrated by this
graphic which uses data from the
IPCC's Fourth Assessment Report - as explained in the relevant
Skeptical Science post - to show where global heating is
going:
You could also argue that in order to fully understand the
heating effect caused by increased concentrations of carbon dioxide
in this atmosphere, it's a good idea to consider all of the
indicators of a warming world possible.
Or... you could ignore them.