Charlie Riedel / AP, file

A flock of geese fly past a smokestack at the Jeffery Energy Center coal power plant near Emmitt, Kansas, in this Jan. 10, 2009 photo.

Greenhouse gases reached a new record level in 2011, the World Meteorological Organization said Tuesday.

The body, an agency of the United Nations, said in a statement that there had been a 30 percent increase in the warming effect on the climate between 1990 and 2011.

It said the level of carbon dioxide – which accounts for about 80 percent of the warming effect – and other so-called greenhouse gases such as methane and nitrous oxide had reached the carbon dioxide-equivalent of 473 parts per million in 2011.

The three gases are closely linked to human activities such as fossil fuel use, deforestation and intensive agriculture.

Further warming
WMO Secretary-General Michel Jarraud said in the statement that billions of tons of carbon dioxide emitted since the start of the industrial age in 1750 would “remain there for centuries, causing our planet to warm further and impacting on all aspects of life on earth.”

“Future emissions will only compound the situation,” he said.

Jarraud said about half of the carbon dioxide emitted as a result of human activity had been absorbed by carbon sinks such as forests and oceans.

“But this will not necessarily continue in the future,” he said. “We have 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.”

“There are many additional interactions between greenhouse gases, Earth’s biosphere and oceans, and we need to boost our monitoring capability and scientific knowledge in order to better understand these,” he added.

Ed Jones / AFP - Getty Images, file

Heavy traffic passes Tiananmen Square outside the opening session of the Chinese Communist Party's five-yearly Congress at the Great Hall of the People in Beijing on Nov. 8.

A warmer, more acidic ocean poses a threat to coral and shellfish.

In July, researchers found that coral reefs had collapsed along Panama's Pacific Coast for 2,500 years due to natural climate cycles.

Coral in Caribbean, Florida in sharp decline, 'no signs of slowing,' report finds

Study co-author Richard Aronson, a biology professor at Florida Institute of Technology, said the discovery showed that reducing greenhouse gas emissions should prevent this from happening again or enable the coral to recover if there was a widespread collapse.

Reuters contributed to this report.

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