When the results of the review finally arrived in July, however, they actually recognized and criticized such confusion. Steve Jones, emeritus professor of genetics at University College London, who carried out part of the review, praised the BBC for “its high quality… clear, accurate and impartial” science coverage. But he added that at times an “over-rigid” application of editorial guidelines blinded the BBC to the “non-contentious” nature of some stories and led it give “undue attention to marginal opinion.”

That view of the BBC’s coverage echoed a more forceful reproach that former BBC correspondent and editor Mark Brayne made in September 2010, when he told CliamteProgress’s Joe Romm that:

On climate change, that BBC journalistic urgency to be seen to be fair now means, after a period between Al Gore’s Inconvenient Truth and the disaster of Copenhagen when global warming was everywhere in the output, that the Corporation has been bending over backwards to reflect the opposite, sceptical view.

That’s going a bit far. Asked about Brayne’s comment at the time, BBC spokeswoman Laura Zetterberg wrote in an e-mail:

We cover a range of environmental and scientific stories and will continue to do so in an impartial and open minded way, examining and weighing up all the material facts. We don’t endorse a specific argument - our job is to help audiences understand the debates around climate change and ensure that our coverage represents a range of views and interpretations.

That’s a perfectly reasonable response, as long as BBC editors and reporters adhere to the impartial review’s strong admonition to avoid “false balance.” They seem to be doing just that.

The decision to offer Frozen Planet’s climate-change episode as an optional extra is, for the most part, an entirely different matter, although it does lend credence to accusations that the BBC’s climate coverage isn’t as vigorous as it used to be. Its marketing strategy may be fairly “standard,” as it claims, but if the last episode’s format was so different that it set it apart from the others, one has to question the episode’s editorial approach.

A complete and comprehensive series about the poles simply must include a discussion of climate change, and it’s up to the journalists involved to make that discussion is cohesive, so that viewers get the full picture, rather than six-sevenths.

If you'd like to get email from CJR writers and editors, add your email address to our newsletter roll and we'll be in touch.

Curtis Brainard writes on science and environment reporting. Follow him on Twitter @cbrainard.