(Photo: Prof. Thomas Pettke, Institute for Geology, University Bern)

Cough pastilles? Ingredients for your Christmas baking?
No, these green crystals, which can be up to a centimetre in size, are actually olivine, the major constituent of the earth’s mantle.

This is what it looks like in vulcanic rock, in this case from Mount Erebus in Antarctica. (Photo by Hannes Grobe, Alfred Wegener Institute).
So what is the green rock doing on the ice blog? Well when olivine weathers and decomposes, it can remove carbon dioxide from the atmosphere. Scientists have been conducting experiments to find out how much, and whether artificially weathering the mineral could help counteract ocean acidification.
Researchers from the Alfred Wegener Institute for Polar and Marine Research in the Helmholtz Association and the KlimaCampus of Hamburg University have just published some model calculations. They say around a ton of olivine dissolved in water would be necessary for each ton of CO2 that could be transferred from the atmosphere to the ocean using this method.They assume the method is not suitable to neutralise present-day greenhouse gas emissions completely, but could be interesting on some scale as just one factor of many.
The Alfred Wegener Institute stresses it is not out to pave the way for the commercial implementation geoengineering measures with this research. “It makes an important contribution to improving the scientific database on geoengineering methods,” says Prof. Karin Lochte,the Director of the Institute.
Given the lack of progress on the large-scale emissions reductions that would be necessary to keep global warming to the 2 degree target, it’s hardly surprising that there is a strong interest in techniques like geo-engineering, whether it be installing mirrors in space or measures like this one.
Of course there are plenty of risks involved. The recent Biodiversity Conference in Nagoya, Japan, called for more information to help assess the potential effectiveness and the risks of geoengineering to the environment and biodiversity.
There’s more detail on all this on the AWI website

We haven’t heard a lot about the iron fertilisation controversy in the Antarctic for a while – at least not in the mainstream media.

(The German research vessel Polarstern, belonging to the Alfred Wegener Institute for Polar and Marine Research, conducting the research with Indian partners).

– See blog entries of 9.-15-1-2009 for the background –
Are you surprised to hear that the controversial experiment did not produce the desired results? Artificially fertlizing the ocean with iron is not a way to substantially reduce the concentration of CO2 in the atmosphere!
It seems the scientists on board the Polarstern were surprised by what did actually happen during the German-Indian experiment.

Mark Mattox has also been following this saga closely and conducted interviews both with the AWI and the ETC for this week’s edition of Living Planet, now available online.
Interview with Ulrich Bathmann, AWI
Interviw with Jim Thomas of the ETC

AWI insists it has looked into potential effects on the environment and biodiversity.
But the German Environment Ministry is quoted in a German newspaper and news agencies as having expressed concern that Germany’s credibility as a leading power in the protection of biodiversity could be undermined by this experiment.
Yes indeed, Minister Gabriel.
One just wonders how this could get this far, with the ship already steaming ahead to the Antartic, without the concerns of environment groups and the Convention on Biodiversity issue being adequately addressed.
The Research Ministry (which provides a considerable amount of funding to the AWI), is now having the project examined by 2 independent scientific bodies.
Let’s see what happens next.
The official “Lohafex” position on the project and the controversy

A few more facts about the iron fertilization idea. Why am I talking about this now? It’s not new, but the increasing concern about the urgency of combatting climate change and the fact that this large-scale experiment is underway in nature, with as yet unresearched possible consequences, make this a good time to take a closer look.
First a bit more background:
Scientists believe “fertilizing” the ocean surface with trace amounts of iron will lead to blooms of phytoplankton, which soak up carbon dioxide in the marine plants. When the phytoplankton die, they sink to the depths of the ocean, with the carbon safely “locked” inside their cells, potentially storing it for decades or centuries in sediments on the ocean floor.
The trouble is we don’t know exactly how much carbon can be captured and stored this way, for how long, or, more crucially, what it means for the ecosystems of the ocean. This is being referred to as “geo-engineering” and sometimes seems to be taking us into the realms of science fiction stories. What does it mean for the species in the ocean, ocean acidity or the level of oxygen in the water?
Some scientists even fear it could lead to the release of nitrous oxide, another powerful greenhouse gas.
Interest in ocean fertilization is not driven by purely scientific or altruistic considerations. There is a commercial interest. Private companies have been working on the idea, because carbon credits can be sold.
It’s interesting that there is not a lot of big media coverage of it. The British Mail on Sunday did have a full page on it earlier this month. It outlines the questions – how much algae will sink to the bottom of the ocean, “safely” trapping Co2, and how long will it stay there? It also draws attention to the findings of a British scientist team that tiny particles of iron are released naturally into the sea, in the Southern Ocean, when icebergs melt. This proof that iron is occurring naturally in the region is, according to the paper, what led to the UN giving permission to move ahead with the experiment.
“Will green algae save the world from global warming?”
Nevertheless, the planned experiment is relatively large in scale and expected to produce a green algae bloom visible from space. Sceptical scientists say the negative effects may not become obvious until it’s too late to do anything about it.
More background on the Treehugger website