the climate brief Accurate Reporting of Climate Science

Algae under Arctic sea ice - ‘certainly not going to solve our CO2 problem’

• 12 Jun 2012, 14:00
• Verity Payne

We've found a 'solution' to the problem of increasing atmospheric carbon dioxide - or at least we have according to some commentators, who have made an impressive leap of reasoning from scientists discovering large algal blooms beneath thinning Arctic sea ice, to the suggestion that the blooms might "stave off the effects of global warming."

It's quite a claim. The reality is somewhat different, as we found out when we checked with the scientist who conducted the research.

A new paper, published in the journal Science last week, reveals that scientists have unexpectedly found big blooms of algae beneath Arctic sea ice. It seems that the thinning Arctic sea ice lets sunlight penetrate through to the ocean below, allowing these light-dependent algae to thrive and to grow faster than similar blooms out in open water.

The research paper says that the presence of these fast-growing algal blooms means that the amount of photosynthesis occurring in the Arctic Ocean has probably been underestimated, and might be as much as ten times higher than previously suggested.

Since photosynthesis is the process by which algae draws carbon dioxide out of the atmosphere and into the ocean, this algae growth might provide a negative feedback to Arctic sea ice melt, with more algae trapping more carbon dioxide, meaning there's less carbon dioxide available to cause warming.

It's entirely feasible that there might be a negative temperature feedback from the algae, although it seems unlikely that it would be big enough to counteract 'Arctic amplification' - the Arctic is warming at about twice the global rate, largely thanks to the loss of sea ice.

And a negative feedback which slows climate change slightly is a very different thing to 'solving' the problem altogether. The Science paper does not claim that these blooms are going to solve global warming, and more research is needed to fully determine the impact of this finding on global carbon cycles and the Arctic ecosystem.

We spoke with Professor Kevin Arrigo of Stanford University, a lead author of the paper. He told us:

"It is a negative feedback, but a very small one. It certainly is not going to solve our CO2 problem!"

So there you go - claims of this being a solution to our carbon dioxide problem are overselling the conclusions of this research by quite some way.

As an aside, we've pointed out that a significant amount of the Daily Mail's coverage of climate science over the past few months has been inaccurate, based on partisan blogs, and under some spectacularly misleading headlines. So it seems only fair to point out that the Mail coverage of this report was accurate, and with a reasonable headline: "'Like finding the Amazon rainforest in the Mojave Desert': Shock finding of 'massive' algal bloom under the Arctic ice". Encouraging stuff from the Mail.

While it's probably too much to hope for from lobby groups, we'd like to see the end of the media exaggerating climate findings for the sake of a good headline. Overstating climate findings - whether proclaiming a climate cure or a climate apocalypse - simply confuses matters. As we've said before, it's just not helpful.