How Defra’s new emissions stats only tell half the story1

You almost certainly won’t have spotted the publication of Defra’s new set of statistics on agriculture and climate change yesterday. But before you nod off, check out this clever piece of spin by the statisticians.

Between 1990 and 2009, total greenhouse gas (GHG) emissions from UK agriculture are estimated to have fallen by 21%.

So far, so good: it looks like British farmers have been doing their bit with cutting carbon. And assuredly many have – whether that’s meant cutting excessive fertiliser use, using biofuels to run farm machinery or planting more trees.

But then take a look at this chart. It shows UK agricultural self-sufficiency – the extent to which we grow our own food compared to relying on imports – and is plotted using official data available on the Defra website prepared for another publication.

Notice anything similar between the two graphs?

Could it possibly be that a continuous decline in UK agricultural production over the past two decades helps explain the resultant drop in agricultural emissions?

I’ll leave readers to speculate.

But whilst there is no statistical analysis of this in the report released yesterday, it does at least acknowledge the strong possibility that it is happening – and warns against it being confused for real emissions savings.

As the report states in its introduction: “A decline in agricultural activity in the UK may well lead to a decline in domestic GHG emissions (and vice versa), but …  As in other sectors, it would not make sense to drive down emissions from UK agriculture by relying more on the import of products that are at least as GHG intensive: this would effectively export the emission effect of food consumption, causing ‘carbon leakage’.”

But until we start to measure the emissions we’re outsourcing, and work to either plug the leaks or alter consumption patterns, official statistics will continue to tell only half the story.