Climate change: Greenhouse gas concentrations again break records

Nov 25, 2019
New Delhi:  Atmospheric concentrations of carbon dioxide and other greenhouse gases once again reached new highs in 2018, a media report said on Monday.

Though the increase in CO2 was just above the average rise in the last decade, the levels of other warming gases like methane and nitrous oxide had surged by above average amounts, a BBC report quoted the World Meteorological Organization (WMO) as saying.

It said that since 1990, there was an increase of 43 per cent in the warming effect on the climate of longlived greenhouse gases.

The WMO report looks at the concentrations of warming gases in the atmosphere rather than just emissions.

Emissions refer to the amount of gases that go up into the atmosphere due to the use of fossil fuels, such as burning coal for electricity and from deforestation whereas concentrations are what’s left in the air after a complex series of interactions between the atmosphere, oceans, forests and land.

About 25 per cent of all carbon emissions are absorbed by the seas, and a similar amount by land and trees.

With the use of data from monitoring stations in the Arctic and across the world, researchers said that in 2018, CO2 concentrations reached 407.8 parts per million (ppm), compared with 405.5 ppm a year earlier.

This increase has been above average for the last 10 years and 147 per cent of the “pre-industrial” level in 1750.

The WMO also records the concentrations of other warming gases, including methane and nitrous oxide. About 40 per cent of the methane released into the air comes from natural sources and 60 per cent from human activities like cattle farming, rice cultivation and landfill dumps.

Methane is now at 259 per cent of the pre-industrial level. The increase over the past year was higher than both the previous annual rate and the average over the past 10 years.

“There is no sign of a slowdown, let alone a decline, in greenhouse gases concentration in the atmosphere despite all the commitments under the Paris agreement on climate change,” the report quoted WMO Secretary-General Petteri Taalas as saying.

“We need to translate the commitments into action and increase the level of ambition for the sake of the future welfare of mankind,” he added.

He said the last time our planet experienced comparable concentration of CO2 was three to five million years ago when the temperature was 2-3 degree Celsius warmer and sea level 10-20 metres higher than now.

Preliminary findings from this study, published during the UN Secretary General’s special climate summit last September, indicated that emissions continued to rise during 2018.

These reports will help delegates from almost 200 countries when they meet in Madrid next week for COP25, the annual round of international climate talks. IANS