Last year at the UN climate change talks in Cancun, it was agreed that cutting emissions sufficiently to limit the world's temperature increase to 2°C would require a far‑reaching transformation of the global energy system. To limit the world's temperature increase to 2°C, it was agreed that the long-term concentration of greenhouse gases in the atmosphere would need to be limited to around 450 parts per million of carbon-dioxide (CO2). Sadly, the International Energy Agency has just released figures indicating that energy-related CO2 emissions in 2010 were the highest ever, reaching 30.6 Gigatonnes (Gt). This means that to achieve the 2020 target, where emissions must not be greater than 32 Gt, emissions will need to rise less over the next ten years in total than they did between 2009 and 2010.

"Our latest estimates are another wake-up call," said Dr Fatih Birol, Chief Economist at the IEA who oversees the annual World Energy Outlook, the Agency's flagship publication.

"The world has edged incredibly close to the level of emissions that should not be reached until 2020 if the 2ºC target is to be attained. Given the shrinking room for manœuvre in 2020, unless bold and decisive decisions are made very soon, it will be extremely challenging to succeed in achieving this global goal agreed in Cancun."

The IEA estimates that 40% of global emissions came from OECD countries in 2010, but OECD countries only account for 25% of emissions growth compared to 2009. Non-OECD countries - led by China and India - saw much stronger increases in emissions as their economic growth accelerated.

That said, OECD countries emitted 10 tonnes of CO2 per capita on average, compared with 5.8 tonnes per capita for China, and 1.5 tonnes per capita in India.

In terms of fuels, 44% of the estimated CO2 emissions in 2010 came from coal, 36% from oil, and 20% from natural gas.