A report (PDF) by scientists shows that emissions are outpacing the ability of ocean and land carbon sinks to soak up carbon dioxide from the atmosphere, according to the National Oceanic and Atmospheric Administration (NOAA). They are concerned that if natural sinks can't keep pace with the increased CO2 emission then the impacts of global warming will accelerate over the next century.
A recent study from the International Union for Conservation of Nature concluded that marine ecosystems including seagrass meadows, mangroves and salt marshes have a much greater capacity to trap carbon than land carbon sinks such as forests, and should be protected.
Two NOAA scientists were among a team of 31 who contributed to the Global Carbon Project report and the recent article, Trends in the sources and sinks of carbon dioxide, published in Nature Geosciences.
The team created a global CO2 budget from 1959 to 2008. Researchers say over this time period an average of 43 percent of each year's CO2 emissions remained in the atmosphere with a spike in global CO2 emissions from 2000 and 2008. This study also took into consideration emissions from changing land use, such as deforestation, logging and cultivation of cropland soils.
The study finds (PDF) that CO2 emissions have increased by 29 percent between 2000 and 2008 primarily due to increased manufacturing in developing countries and use of coal as fuel source. Coal is now the largest fossil-fuel source of CO2 emissions, according to the study, with over 90 percent of the growth in coal emissions from China and India.
Researchers also estimate that the amount of carbon dioxide that remains in the atmosphere and contributes to greenhouse warming has increased from 40 percent to 45 percent of emissions between 1959 and 2008.
Click here for key findings of the study.