SINGAPORE — The latest tally of greenhouse-gas emissions blamed for warming the world shows that China has emerged as the top polluter, ahead of the United States, by an increasingly big margin.

Released last month, the scientific findings of the Global Carbon Project show that, in 2007, over half the world's emissions came from high-growth developing economies led by China and India, and that this share is rising because emissions from developed economies are growing less fast.

The project's Australia-based executive director, Pep Canadell, said China alone accounted for 60 percent of emissions growth last year. This was due to China's heavy reliance on coal for generating electricity and oil for transport fuels. Yet the world's most populous nation is also a global leader in harnessing renewable energy, particularly hydro, wind, solar and biomass power.