Global CO2 emissions exceed IPCC worst case scenario

A comprehensive report released today by the Global Carbon Project contains the grim news that global CO2 emissions are exceeding the most pessimistic IPCC emissions scenario. The annual mean growth of atmospheric CO2 increased from 2.0 ppm (parts per million) during the first half of the decade and from 1.8 ppm in 2006,  to 2.2 ppm in 2007.  This increase in the growth of emissions makes IPCC stabilization scenarios of 450 ppm – 650 ppm doubtful.

Annual mean growth rates of atmospheric CO2 concentration.

The report “Carbon budget and trends 2007” is a sobering synthetic analysis of the world’s carbon budget, including the sources and sinks of CO2 parsed by nation, continent, human activity and ecosystem.

Despite the increasing international sense of urgency, the growth rate of emissions continued to speed up, bringing the atmospheric CO2 concentration to 383 parts per million (ppm) in 2007.  Anthropogenic CO2 emissions have been growing about four times faster since 2000 than during the previous decade, despite efforts to curb emissions in a number of Kyoto Protocol signatory countries.

Dr. Pep Canadell, executive director of the Global Carbon Project said “This new update of thecarbon budget shows the acceleration of both CO2 emissions and atmospheric accumulationare unprecedented and most astonishing during a decade of intense international developments to address climate change.”

Fossil Fuel Emissions: Actual vs. IPCC Scenarios

Some of the report highlights are excerpted below:

Atmospheric CO2 growth: Annual mean growth rate of atmospheric CO2 was 2.2 ppm per year in 2007 (up from 1.8 ppm in 2006), and above the 2.0 ppm average for the period 2000-2007. The average annual mean growth rate for the previous 20 years was about 1.5 ppm per year. This increase brought the atmospheric CO2 concentration to 383 ppm in 2007, 37% above the concentration at the start of the industrial revolution (about 280 ppm in 1750).  The present concentration is the highest during the last 650,000 years and probably during the last 20 million years. [ppm =  parts per million].

Regional fossil fuel emissions
The biggest increase in emissions has taken place in developing countries, largely in China and India, while developed countries have been growing slowly. The largest regional shift was that China passed the U.S. in 2006 to become the largest CO2 emitter, and India will soon overtake Russia to become the third largest emitter. Currently, more than half of the global emissions come from less developed countries. From a historical perspective, developing countries with 80% of the world’s population still account for only 20% of the cumulative emissions since 1751; the poorest countries in the world, with 800 million people, have contributed less than 1% of these cumulative emissions.

Conclusions: Anthropogenic CO2 emissions have been growing about four times faster since 2000 than during the previous decade, and despite efforts to curb emissions in a number of countries which are signatories of the Kyoto Protocol. Emissions from the combustion of fossil fuel and land use change reached the mark of 10 billion tones of carbon in 2007. Natural CO2 sinks are growing, but more slowly than atmospheric CO2, which has been growing at 2 ppm per year since 2000. This is 33% faster than during the previous 20 years. All of these changes characterize a carbon cycle that is generating stronger climate forcing and sooner than expected.


Global Carbon Project (2008) Carbon budget and trends 2007, [, 26 September 2008]”

2 thoughts on “Global CO2 emissions exceed IPCC worst case scenario

  1. Is it really grim news that CO2 emissions have exceeded the worst case scenario, when at the same time temperature in the atmosphere and ocean have plummeted? On the contrary I would say it indicates that the IPCC worst case scenarios on temperature is exaggerated.

  2. Pingback: Gravity’s Rainbow » Blog Archive » Faster and faster

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