Part of: Prelims and GS III – Conservation related issues; Climate change
Context A report from the World Meteorological Organisation (WMO) said the increase in CO2 from 2019 to 2020 was slightly lower than that observed from 2018 to 2019.
However, it is higher than the average annual growth rate over the past decade.
Updated data shows that the pandemic disruption in 2020 didn’t significantly dent overall greenhouse gas emissions.
Key Findings
The National Oceanic and Atmospheric Administration (NOAA) Annual Greenhouse Gas Index (AGGI) shows that from 1990 to 2020, radiative forcing (warming effect) by long-lived greenhouse gases (LLGHGs) increased by 47%, with CO2 accounting for about 80% of this increase.
Methane: The increase from 2019 to 2020 was higher than that observed from 2018 to 2019 and also higher than the average annual growth rate over the past decade.
Nitrous oxides: The increase was higher and also than the average annual growth rate over the past 10 years.
Carbon dioxide (CO2): It reached 413.2 parts per million in 2020 and is 149% of the pre-industrial level.
Roughly half of the CO2 emitted by human activities today remains in the atmosphere. The other half is taken up by oceans and land ecosystems.
Concerns raised
WMO has flagged concern that the ability of land ecosystems and oceans to act as ‘sinks’ may become less effective in future, thus reducing their ability to absorb CO2 and act as a buffer against larger temperature increases.
It has also pointed out that At the current rate of increase in greenhouse gas concentrations, we will see a temperature increase by the end of this century far in excess of the Paris Agreement targets of 1.5 to 2 degrees Celsius above pre-industrial levels.
