Back to ocean acidification, greenhouse gas, etc

Here's a round up of interesting stuff about greenhouse issues, all in one post so that readers who don't believe in it can skip right over!

* There's a study out on Great Barrier Reef coral which indicates ocean acidification (lowering of the ocean pH) has already been underway for some time. (Seems very technical work, and I wouldn't be surprised if other scientists argue about this.)

* It seems that at least some molluscs get heavier shells with more CO2 in the water, rather than lighter. This paper is based on some tank experiments, and is pretty noteworthy because it seems to show how little is properly understood about the biological processes in calcification.

The authors note, however, that heavier shell production (or just normal shell production) in some species seems to be at a price. (Like less muscle, reproductive changes.) It's still not a very encouraging sign that everything is OK under increased ocean acidification. (In fact, I seem to recall some article that was about a period in prehistory when molluscs ruled the oceans. Must go looking for that.)

* Ross Gittens writes this morning about the Rudd ETS and Penny Wong's recent counterattack on the idea that individual efforts to "reduce carbon footprint" don't change emissions overall. Ross says Rudd and Wong are being misleading in their claims:

It's true only in an arithmetic sense that anything we do "contributes directly" to Australia meeting its emissions target. Everything contributes to the bottom line of the sum. But, because the bottom line is controlled under the scheme, any helpful contribution we might make just leaves more scope for others to make unhelpful contributions.

When Wong says strong actions on our part help make it easier for governments to set lower emissions targets in future, the future she means is after 2020. As it stands, the only changes governments can make under the scheme are to the "trajectory" or path we travel to get to an unchanged destination level of emissions in 2020.

Why has the Government constructed its scheme in such a strange, off-putting way, which fact it has then wanted to conceal and obfuscate?

So, the point that individual actions to live more frugally leaves more room for industry to increase CO2 is correct.

(As I understand it, a carbon tax can't be really based on a set target, so there is a degree of guesswork involved in knowing where to set the tax so as to achieve a desired level of reduction. However, monitoring its progress should be a much simpler task, I would have thought; and you remove a lot of the "money for nothing" aspects of permit trading and derivatives markets that make me so sceptical of ETS as a concept.)

* I asked over at Harry Clarke's blog last night, but don't know the answer yet. Has anyone done any extensive work on how a carbon tax would work? ETS has been in favour for so long, I don't think there has ever been much in the way of discussion in the popular media about how you could make a carbon tax work.

My assumption had been that a carbon tax would mean each country concentrates on assessing it's own emissions, and the effect the tax is having on them. However, I suppose it is possible to have a system of credits involved too, and if credits could be gained for overseas offsets, you would have much of the same rorting possible as has been shown under the present European ETS.