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GENEVA —The battle to stem climate change may be lost as new information indicates the Amazon rain forest is turning from a carbon sink - or area that absorbs CO2 - into a source of carbon dioxide, the World Meteorological Organization warns.
The latest edition of the WMO's Greenhouse Gas Bulletin reports emissions of carbon dioxide, methane, and nitrous oxide once again broke all records last year.
The U.N. agency's report warns the concentrations of these greenhouse gas emissions into the atmosphere are driving climate change. It says carbon dioxide, the single most important greenhouse gas, accounts for approximately 66 percent of the warming effect on the climate.
The secretary-general of the World Meteorological Organization, Petteri Taalas, says about half of CO2 emissions remains in the atmosphere for centuries. He says the other half is taken up by oceans and land ecosystems.
He says it is not clear for how much longer forested areas, often referred to as the lungs of the Earth, will continue to act as effective carbon sinks.
"We have already seen some alarming indications that, for example, Amazonian rain forest ecosystem, which used to be a major sink of carbon, has become now a source of carbon, which is alarming," Taalas said. "And this is related to deforestation in the area and also changes in local climate because of this deforestation."
Oksana Tarasova, who heads the WMO's Atmospheric and Environment Research Division, says the WMO only now is revealing this new finding because it has taken nine years of observation to gather the measurement data set needed to understand the changes taking place. She says not all of the Amazon forest is turning from a carbon sink to a net producer of carbon.
"So, the Western part of the Amazonia still continues to work as a carbon sink at this point. But we do not know for how long that will continue this way," Tarasova said. "We are making the measurements there and keeping our track on what is happening there. ... I would take the whole Amazonia as a whole that is seen that it is a sink, but its capacity is substantially reduced."
Meteorologists say climate change negotiators at an upcoming conference in Scotland must take concrete action and make concrete pledges to reduce carbon dioxide emissions.
They say setting carbon neutral targets will not work in stemming climate change. They also warn the world is heading toward a temperature rise of 2.5 degrees Celsius by the end of this century. This, they say, is far more than the Paris Agreement target of 1.5 to two degrees Celsius above pre-industrial levels.