‘CO2 emissions in 2020 above decadal average’

What is the News?

The World Meteorological Organization (WMO) has released its Greenhouse Gas Bulletin Report ahead of COP26 in Glasgow, UK.

What are the key findings of the Report?

Carbon Dioxide(CO2)

Carbon dioxide (CO2) is the most significant greenhouse gas. It has reached 413.2 parts per million in 2020 and is 149% of the pre-industrial level. 

However, the increase in CO2 from 2019 to 2020 was slightly lower than that observed from 2018 to 2019 but higher than the average annual growth rate over the past decade. 

This is despite the approximately 5.6% drop in fossil fuel CO2 emissions in 2020 due to restrictions related to the pandemic.

Absorption of CO2

Roughly half of today’s human-emitted CO2 remains in the atmosphere and the other half is absorbed by oceans and land ecosystems, the Bulletin flagged.

However, the ability of land ecosystems and oceans to act as “sinks” may become less effective in future, thus reducing their ability to absorb carbon dioxide and act as a buffer against larger temperature increases.

Methane

Methane is a powerful greenhouse gas which remains in the atmosphere for about a decade. Methane accounts for about 16% of the warming effect of long-lived greenhouse gases.

Approximately 40% of methane is emitted into the atmosphere by natural sources (for example, wetlands and termites), and about 60% comes from anthropogenic sources (for example, ruminants, rice agriculture, fossil fuel exploitation, landfills and biomass burning).

Currently,  Methane (CH4) is 262% of the levels in 1750 when human activities started disrupting Earth’s natural equilibrium. 

Nitrous Oxide

Nitrous Oxide is both powerful greenhouse gas and an ozone-depleting chemical. It accounts for about 7% of the radiative forcing by long-lived greenhouse gases.

N2O is emitted into the atmosphere from both natural sources (approximately 60%) and anthropogenic sources (approximately 40%), including biomass burning, fertilizer use, and various industrial processes.

Currently, nitrous oxide (N2O)  is 123% of the levels in 1750 when human activities started disrupting Earth’s natural equilibrium. 

Source: This post is based on the article “CO2 emissions in 2020 above decadal average” published in “The Hindu” on 26th October 2021.