In the final episode of the BBC's Africa documentary, broadcast
last week, veteran nature presenter Sir David Attenborough said
that "some parts of the continent have become 3.5 degrees Celsius
hotter in the past 20 years".
This prompted a fair bit of discussion, and rightly so - the BBC
has since called the statement "disputable" and removed it from
repeats of the programme. But if the BBC got it wrong, what could
it have said? Here we look through the scientific literature to
find some material the BBC could have used instead.
The issue came to light with a flurry of inquisitive Twitter
users expressing surprise at the 3.5 degree claim shortly
the programme aired last Wednesday. The Guardian's
Leo Hickmantook a closer look with a blog post headlined 'BBC
exaggerated climate change in David Attenborough's Africa' - and
the story was widely picked up in other papers. The
Telegraph and the
Daily Mail all covered the story yesterday - the latter
calling the episode "an embarrassing climbdown over climate change
The BBC swiftly
removed the offending phrase from Sunday's repeat, with
the admission that Attenborough's words "should have been more
carefully scripted". All that remains in the programme as broadcast
is a rather vague statement that "Africa's climate is certainly
Looking for temperature trends across Africa is not like looking
for trends in the UK or elsewhere in the Northern Hemisphere.
Temperature measurements are only
quite patchyacross the continent, and where measurements do
exist they don't extend very far back in time.
With temperature data only available for relatively short
periods of time, it's harder to spot long term changes - or trends.
And gaps in the geographical coverage make it hard to see how
widespread any detected trends are.