The UK's summary of greenhouse gas emissions for 2009 are now out.

So, what did 2009 mean for climate change?

2009 was defined by one monolithic event: the recession. Whilst damaging beyond count for the economy, the recession was not bad in terms of greenhouse gas emissions, which fell markedly.

The pertinent statistics

• Greenhouse gas emissions in 2009 fell by 8.7% compared to 2008 (566.3 million tonnes of carbon dioxide equivalent vs 620.5 million tonnes)
• In what sectors can we see these falls?
  • Energy supply: 11% fall
  • Business: 11.8% fall
  • Industry: 36.5% fall
  • Transport: 4.2%
  • Residential: 5.8%
• Carbon dioxide itself fell by 9.8%

How do we account for the reductions?

Decreased economic activity is certainly a factor. Whether or not we can view this as a 'good' thing for the environment is a moot point - the recession certainly caused a lot of environmental and sustainability spending to be scaled back.

At LoCO2 Energy, we would love to assume that the reduction in carbon emissions could be accounted for by increased uptake of renewable energy in homes and businesses. However, it would appear that the reductions can be accounted for on the most part by the growth of another zero carbon, and controversial, energy source: nuclear fusion.

An interesting aside

One of the big victories in the carbon emission battle over the last 20 years in the UK has been methane emissions.

Methane is a comparatively small component of total greenhouse gas emissions (around 8% in the UK) but, pound for pound, has far more global warming potential than carbon dioxide.

Between 1990 and 2009 methane emissions fell by a whopping 61%.

There are two main sources of methane emissions in the UK, which together account for more than two thirds of all emissions.

• Agriculture: 41%
• Landfill: 37%

There were major reductions in the sources for these emissions:

• Landfill: down by 72%
• Agriculture: down by 19%

The statistical release doesn't go into any detail about how these reductions were achieved, particularly at landfill sites, but you might suggest that less rubbish going to the dumps (perhaps through an increase in recycling) and more capture of landfill gas for energy production may take some of the credit.