Greenhouse gas levels reach record high

MANILA, Philippines — The levels of heat-trapping greenhouse gases in the atmosphere have reached another record high, according to a new report issued by the United Nations weather agency.

The World Meteorological Organization (WMO) said this record reveals that there is no sign of reversal of the upward trend responsible for climate change, sea level rise, ocean acidification and extreme weather.

The WMO Greenhouse Gas Bulletin shows that global concentrations of carbon dioxide (CO2), methane and nitrous oxide have been increasing steadily over the past years. The report also notes a resurgence of a potent greenhouse gas and ozone-depleting substance called CFC-11, which is regulated under an international agreement to protect the ozone layer. 

The bulletin reports specifically on atmospheric concentrations of greenhouse gases, which are what remain in the atmosphere following a complex process of emissions and absorptions. 

“The science is clear. Without rapid cuts in CO2 and other greenhouse gases, climate change will have increasingly destructive and irreversible impacts on life on Earth. The window of opportunity for action is almost closed,” said WMO secretary-general Petteri Taalas.

This new report, the WMO said, adds yet another building block of scientific evidence to inform decision-makers at the upcoming UN climate change conference – the COP 24 – planned from Dec. 2 to 14 in Poland. The key objective of this meeting is to adopt an implementation plan for the 2015 Paris Agreement.

Describing climate change as a “survival issue,” the UN said the world needs to move as soon as possible toward a green economy, generate low carbon technologies and move for a cultural shift in production and consumption patterns to keep temperatures from rising more than 1.5 degrees Celsius.

Since 1990, there has been a 41 percent increase in the warming effect by the various greenhouse gases on the climate – known as “radioactive forcing.” CO2 specifically accounts for about 82 percent of the increase in radioactive forcing over the past decade, according to figures quoted in the WMO report.   

“The last time the Earth experienced a comparable concentration of CO2 was three to five million years ago, when the temperature was 2 to 3°C warmer and sea level was 10 to 20 meters higher than now,” Taalas said. 

The WMO report comes on top of the evidence presented in the Intergovernmental Panel on Climate Change special report on global warming issued in October, which sounded the alarm on the need to reach zero net emissions of CO2 by mid-century to keep temperature increases to below 1.5°C.