BBC makes a locally-sourced meal of discussing Arctic sea ice melt
- 12 Sep 2012, 10:33
- Verity Payne and Freya Roberts
The BBC's fondness for
pitting non-experts against each other over particularly
complex areas of climate science reached surreal heights in a
segment on Arctic sea ice loss on
Newsnight last week. The debate between Conservative MP Peter
Lilley and the Green Party's new leader Natalie Bennett eventually
segued into an argument over the merits of locally-sourced
food.
The segment begins by revealing "new evidence suggesting melting
Arctic ice will have a dramatic effect on our climate", based on
calculations by University of Cambridge ocean physicist Professor
Peter Wadhams, who argues
that Arctic sea ice loss "is massively compounding the effects of
greenhouse gas emissions".
Given that scientists are
currently debating the implications of this year's
record-breaking sea ice melt, this statement really deserves to be
followed up by a discussion between Arctic climate experts. That
might be particularly important in this case because, as far as we
can find out, Wadhams's calculations have not yet been published in
a peer-reviewed journal.
Newsnight doesn't go for that approach. Instead it adopts a
format which has become
increasingly familiar at the BBC over the past few months -
orchestrating a fight between a couple of people with completely
opposed views about climate change and what to do about it.
Natalie Bennett, the new leader of the Green Party, focuses on
talking about local food - arguing that shortening food supply
chains will help curb greenhouse gas emissions. Meanwhile, Peter
Lilley MP, who has just written a
report criticising the Stern Review for climate skeptic
thinktank the Global Warming Policy Foundation, sticks to his own
comfort zone, arguing against any response to climate change where
the costs outweigh the benefits.
Neither offer any useful insights on Wadhams's calculations, or
on the current state of the Arctic sea ice.
Setting the scene - North Pole or Arctic
Ocean?
The report kicks off with Susan Watts, Newsnight science editor,
setting the scene: Arctic sea ice has declined since satellite
records began, and this year's summer sea ice melt has set a new
record low extent. She then looks to the future, saying:
"Estimates that the North Pole could be
ice-free in summer in a few years contrast with the official views
of the Met Office, that Arctic summers will not be completely free
of ice before the summers of 2030."
It's worth pointing out here that an ice-free North Pole and an
ice-free Arctic Ocean are quite different. An ice-free North Pole
means the presence of open water at the geographic North Pole, and
could be true even if the whole of the rest of the Arctic Ocean
were covered in sea ice.
A sea ice-free Arctic Ocean, in contrast, means the loss of
nearly all the sea ice in the whole of the Arctic Ocean -
scientists define it as ice coverage going below a specific, low
threshold. Wadhams has predicted both an
ice-free geographic North Pole and
a sea ice-free Arctic Ocean within the coming decade. But on
this occasion, Wadhams is discussing the loss of nearly all the sea
ice in the Arctic Ocean.
New evidence?
Watts then addresses Wadhams's new research. The decline of
Arctic sea ice exposes more open ocean water, which is darker and
can absorb more heat than the reflective sea ice it replaces.
Wadhams calculates that once the Arctic Ocean becomes sea ice-free,
over one per cent of the Earth's total surface will have changed
from reflective sea ice to heat-absorbing open water.
Wadhams suggests, if his
calculations are correct, that the change to the Earth's total
reflectivity caused by losing all Arctic sea ice will have a
warming effect for the whole globe of 1.3 watts per square metre -
Wadhams reckons this to be "the equivalent of about 20 years of
additional carbon dioxide being added by man".
As far as we can find Wadhams's work has yet to be published in
a peer-reviewed journal, and is rather larger than previous
estimates. For example, other
studies
based on observations suggest that the losing all Arctic sea ice
would have a global warming effect of around 0.3 watts per square
metre. And
climate modelling puts the figure even lower.
Lilley on ice
A discussion putting Wadhams' work in context and comparing it
to other similar studies would have clearly been useful.But instead
Newsnight enlisted a couple of politicians to offer generic and
predictable talking points about climate change.
Lilley even asserts that he "was told to come on [Newsnight] and
not discuss the science" - this seems an unusual booking approach
from Newsnight, given the starting point of the segment. But that
doesn't stop him from dismissing Wadhams's work:
"[Newsnight has] presented something
which purports to be new evidence that contains nothing new, which
is tendentious, not peer-reviewed, by a well known alarmist, and
absolute bunkum... compared with the IPCC."
Lilley sticks to projections from the Intergovernmental Panel on
Climate Change (IPCC)'s 2007 report, arguing that the Arctic
shouldn't be ice free until at least the 2070s.
But there are good reasons to move beyond the IPCC on this
particular issue. IPCC models have since been found to underestimate
Arctic sea ice loss, and
peer-reviewed literature from the last few years does seem to
suggest that we are talking decades rather than centuries before we
see a seasonally ice-free summer - although it's
hard to pinpoint an exact date much more accurately than
this.
Interestingly, Lilley says he agrees with the basic tenets of
climate science and that he is happy "to take the UN
Intergovernmental Panel on Climate Change assessment as a correct
projection of what the likely trends were going to be". Yet, as Bob
Ward has pointed out, in his response to the Stern report he
rejects one the IPCC's fundamental findings.
The odd couple
After this cursory discussion of the sea ice, the discussion
moves on to "what needs to be done, or what can be done" about
man-made climate change. Neither interviewee has anything
particularly new to offer. Lilley suggests we "only do things where
the costs are less than the benefits", while Bennett makes
some general points about the importance of tackling climate change
and developing green industries. She also focuses on
food supply chains, saying:
"Well, what we'd like to do is to
relocalise our industries, bring farming back into the UK, stop
flying peas from Peru and beans from Kenya, we want to bring jobs,
we want to bring industries back into the UK, all of these are
things which are very much positive for the UK and are good for
reducing our carbon emissions at the same time."
Sounds nice, but unfortunately this a rather simplistic view of
the
link between food miles and emissions. For example, other
factors besides where food has come from, such as the use of energy
intensive farm practices or even the energy used in cooking the
product at home, can often make a bigger overall difference to
carbon emissions.
Lilley ends by saying:
"But hang on, I do want to resent the
idea that we should impoverish people of Kenya and Peru by stopping
trading with them. That seems to be manifestly cruel."
A piecemeal assemblage of slightly left-field Arctic sea ice
science and arguments over local food and the Stern review. Read
the rough transcript
- the programme really descends into a bizarre ending of
cross-cutting conversations. It's hard to understand how, over a
year after the BBC Trust reviewed the corporation's science
coverage, paying particular attention to topics such as climate
change, this is what we end up with.