Carbon emissions from fossil fuels rose two per cent last year to an all-time high, leaving earth on a worst-scenario track for global warming, according to scientists.

They also voiced concern for the world's oceans and forests, saying the capacity of these fabled "sinks" to soak up dangerous greenhouse gases was fading.

They placed the spotlight on surging emissions by China and developing countries, explaining that a huge chunk of this carbon comes from exporting goods that are consumed in rich nations.

The paper, published by the peer-reviewed journal Nature Geoscience, comes in the run-up to December 7-18 UN talks in Copenhagen aimed at crafting a pact to combat climate change from 2013.

Global emissions from fossil fuels in 2008 amounted to 8.7 billion tonnes of carbon, an increase of two per cent over 2007, the Global Carbon Project, gathering more than 30 climate specialists, reported.

Emissions last year were 29 per cent higher than in 2000, reflecting a sprint in economic growth this decade, and a massive 41 per cent greater than in 1990, the reference year for the UN's Kyoto Protocol.