BITE BACK - Carbon Attack

Written by staff reporter Tuesday, 23 June 2009 00:00

The increase in temperatures through global warming is already having an effect – the bleaching event of 1998, for instance, lost us 20 per cent of the world’s coral – but the sea is subject to a more insidious consequence of this CO2, and that is its increasing acidification. Since the start of the Industrial Revolution, the pH levels in the sea have been steadily falling, with a drop so far of about 0.1 pH units, but this is rapidly accelerating as we pump out yet more carbon dioxide.

The oceans absorb approximately one third of the CO2 emitted to the atmosphere by the burning of fossil fuels. By the end of the century, we may well be seeing pH changes that are three times greater, and 100 times faster, than those that occurred when the Earth moved out of the ice age. Scientists are just beginning to understand how far-reaching its effects will be. Predictions are that the sea’s pH will drop by 0.4 pH units with a 60 per cent decrease in the concentration of calcium carbonate.

It is this drop in calcium carbonate that could signal the death knell for the many species that form a shell (such as sea urchins, snails and mussels) and for coral reefs, whose whole framework is based on calcium. Even the very basis of the marine food chain, plankton, would be badly affected, particularly the calcareous phytoplankton. Higher forms of marine life, such as invertebrates and fish, are not immune, either: CO2 accumulation leads to acidosis, lowering their resistance and reproductive ability.

We must be mindful of repercussions such as these as we see Gordon Brown’s government deciding to start building coal-fired power stations once again. Coal-fired power generation is historically responsible for most of the excess CO2 in the air today and causes half of all global carbon dioxide emissions. Had the new Kingsnorth power station in Kent been given the go-ahead, which very nearly happened, it would have produced around 8.4 million tonnes of CO2 every year.

The government is clearly still intent on a coal-fired power station programme, but is now stating that no new station can be built unless it can capture and bury at least 25 per cent of its emissions now, and 100 per cent by 2025. That sounds great, and is a huge improvement on its previous plans, but the truth is that carbon-capture technology is a long way from being finished. Furthermore, bearing in mind what is at stake for the world’s oceans, the idea that these new stations could be emitting three tonnes of CO2 for every tonne they capture for the next 15 years seems a highly irresponsible policy to be sanctioning. Just four new stations could emit up to 275 millions tons of CO2 in that time.

The solution is clear. If new coal-fired power stations are to be built, then, if the government is to meet its carbon targets, they need to capture 100 per cent of their emissions from day one, and existing plants also need to be updated. The stakes are just too high to consider any other alternative. If you go to http://findyourmp.parliament.uk/commons/l/ and enter your postcode, it will give you the name of your MP and their email address. Make it clear to them that if they really can’t find an alternative to using coal, then they must allow it only when it can be done in such a way that it doesn’t destroy our seas.