Geoengineering – the “Plan B”
(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
