The highest record for emission of greenhouse gases in the Earth’s atmosphere reached in 2011, according to new data published by the World Meteorological Organization (WMO).
According to WMO’s annual Greenhouse Gas Bulletin report that is released on Tuesday, the amount of carbon dioxide rose to 390.9 parts per million (ppm), up two ppm on 2010 levels. The one of the most important greenhouse gas emitted by humans is carbon dioxide and the increases recorded last year are in line with average rises seen each year over the last decade.
It is responsible for 85% of the increase in radiative forcing over the past decade and 81% over the last five years.
Combined with average yearly rises of 1.5 ppm during the 1990s, the WMO says radiative forcing (the warming effect on our climate) by long-lived greenhouse gases has now increased 30% since 1990.
“These billions of tons of additional carbon dioxide in our atmosphere will remain there for centuries, causing our planet to warm further and impacting on all aspects of life on Earth,” WMO secretary general Michel Jarraud said in a statement.
According to the WMO, about 375 billion tons of carbon has been released into the atmosphere since the industrial revolution began in 1750, with around half this amount being absorbed by carbon sinks. But natural carbon storage facilities like oceans and forests “will not necessarily continue in the future,” say the WMO.
“We’ve already seen that the oceans are becoming more acidic as a result of the carbon dioxide uptake, with potential repercussions for the underwater food chain and coral reefs,” Jarraud said in a statement.
The Swiss-based United Nations agency, which uses data from more than 50 countries to compile the report, also detailed rises in other greenhouse gases including methane and nitrous oxide.
Around 60% of methane released into the atmosphere comes from human activities such as farming, rice agriculture, fossil fuel exploitation, landfill and biomass burning, according to the WMO. In 2011, concentrations reached a new high of 1813 parts per billion (ppb), 259% higher than pre-industrial levels.
Emissions of nitrous oxide — 40% of which are estimated to come from human activity — reached 324.2 ppb, up one ppb on the 2010 figure and 120% higher than pre-industrial times.
Richard Allan, from the Department of Meteorology at the UK’s University of Reading, said the WMO’s latest data confirmed the trend in the rate of rise reported in recent decades.
“What it shows isn’t surprising, but it obviously has very important implications for the future well-being of the planet,” Allan told CNN.
Even if emission rises were halted now, the planet would continue to warm because of the time it takes for the climate system to return to equilibrium, he said.
“We are committed to the warming for a long time, even if we do take strong action against it now,” Allan said.