Those listening closely may have heard a creaking sound emanating from Holyrood this afternoon. Not the sound of another roof beam falling in, but the sound of the all party consensus on climate change being stretched.

The Transport, Infrastructure and Climate Change Committee rejected the Government’s statutory instrument setting out annual climate targets for the next decade.

Were they right to do so? Will it make a difference? It’s actually a difficult call.

The Government plan is slightly more ambitious than that recommended by the Committee on Climate Change. And it reaches the 42% target for 2020. But it relies heavily – perhaps too heavily – on the effective working of the European carbon trading system (the Emissions Trading Scheme or ETS), and starts off very slowly – in contradiction to the SNP’s 2007 manifesto pledge to move immediately to 3% per annum cuts.

The Committee was rightly concerned about the limited ambition of the Government targets until 2013. The Climate Change (Scotland) Act also requires ministers to take account of a fair and safe cumulative budget when setting annual targets. And the shape of the trajectory in the early years makes a much bigger difference to the total cumulative budget than it does later on.

Early and sustained cuts will be essential if Scotland is to not only meet its fine 2020 target, but do so in a way that makes a fair global contribution to addressing the problem.

But on the other hand, there is little point setting more ambitious targets in the next few years if we cannot meet them. Government policy shifts can only deliver so much in a matter of months … you may have noticed that the UK Government’s welcome commitment to the 10:10 campaign goal only applies to Government bodies’ own emissions, not the country’s emissions.

As the Climate Change Minister Stewart Stevenson has emphasised, working to enhance delivery now is more important than setting tougher targets.

But there are things that can be done – or begun – now that will deliver a more rapid decline in emissions. Expanding the universal home insulation scheme, especially if done instead of spending on emissions-generating projects such as a second Forth Crossing, would make a massive difference. Effective peatland management and protection could save millions of tonnes of carbon.

And in the short term there is an even bigger prize in locking in as much as possible of the dramatic emissions cut resulting from the economic recession. UK figures suggest that 2009 emissions were down by over 8%. This isn’t taken account of in the Government’s proposed targets.

We must recognise that some of this reduction will have happened in the ‘traded sector’ – so won’t count directly against the Scottish targets (which treat the traded sector – electricity generation, refineries, other big industry etc – as delivering the European average reduction resulting from the ETS). But estimates suggest transport emissions fell 6.5% and even household emissions 4.5% and, unlike electricity generation, these sources are not covered by the ETS.

So on balance the Committee may have been right to reject the Government’s targets. But if they not to simply delay action, and instead come back with new targets which deliver more ambitious cumulative reductions, they must also show how those targets can be delivered – with practical measures to lock in the ’emissions silver lining’ of the recession.

In addition, we all have to begin to address the shortcomings of carbon trading in the ETS. The recession may have cut emissions, but because of the way the ETS works (or fails to) it means that many companies will

have banked emissions permits that will simply allow them to emit more in the future, while undermining the future price of carbon in the scheme, further discouraging business action to cut emissions.

That won’t be good news for the new UK administration either: the Conservative and Liberal Democrat pledge to provide a floor price for carbon in the ETS might encourage emissions reduction, but could come at a high cost to the public purse. Carbon taxes, or simply tougher regulation, would seem a far better bet for future Scottish, UK and European climate policy.