Goaltide Daily Current Affairs 2021

Oct 26, 2021

Current Affair 1:
Greenhouse Gas Bulletin

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Points given below are very important for Prelims.

The abundance of heat-trapping greenhouse gases in the atmosphere once again reached a new record last year, with the annual rate of increase above the 2011-2020 average. That trend has continued in 2021, according to the World Meteorological Organization (WMO) Greenhouse Gas Bulletin.

Concentration of carbon dioxide (CO2), the most important greenhouse gas, reached 413.2 parts per million in 2020 and is 149% of the pre-industrial level. Methane (CH4) is 262% and nitrous oxide (N2O)  is 123% of the levels in 1750 when human activities started disrupting Earth’s natural equilibrium.

Highlights of the Bulletin

Carbon sinks

  1. 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.
  2. The part of CO2 which remains in the atmosphere, is an important indicator of the balance between sources and sinks. It changes from year to year due to natural variability.
  3. Ongoing climate change and related feedbacks, like more frequent droughts and the connected increased occurrence and intensification of wildfires might reduce CO2 uptake by land ecosystems.
  4. Such changes are already happening, and the Bulletin gives an example of transition of the part of Amazonia from a carbon sink to a carbon source. Ocean uptake might also be reduced due to higher sea surface temperatures, decreased pH due to CO2 uptake and slowing of the meridional ocean circulation due to increased melting of sea ice.

Carbon Dioxide

Carbon dioxide is the single most important greenhouse gas in the atmosphere, accounting for approximately 66% of the warming effect on the climate, mainly because of fossil fuel combustion and cement production.

The globally averaged concentrations for CO2 reached a new high of 413.2 ppm in 2020. The increase in CO2 from 2019 to 2020 was slightly smaller than 2018 to 2019 but larger than the average annual growth rate over the last decade. This is despite the approximately 5.6% drop in fossil fuel CO2 emissions in 2020 due to the COVID-19 restrictions.


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, according to the US National Oceanic and Atmospheric Administration (NOAA). 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).

Reducing atmospheric methane in the short term could support the achievement of the Paris Agreement and help in reaching many Sustainable Development Goals due to multiple co-benefits of methane mitigation.

Nitrous Oxide

Nitrous Oxide is both a powerful greenhouse gas and 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 oceans, soils, biomass burning, fertilizer use, and various industrial processes.

Global human-induced N2O emissions, which are dominated by nitrogen additions to croplands, increased by 30% over the past four decades. Agriculture, owing to the use of nitrogen fertilizers and manure, contributes 70% of all anthropogenic N2O emissions. This increase was mainly responsible for the growth in the atmospheric burden of N2O.

Current Affair 2:
Biodiversity Hotspots:


A biodiversity hotspot is a biogeographic region that is both a significant reservoir of biodiversity and is threatened with destruction.

Conservation International was a pioneer in defining and promoting the concept of hotspots. The Conservation International Foundation (CI) is a non-profit organization that operates internationally in over 30 countries across six continents with a wide range of partners in order to empower societies to responsibly and sustainably care for nature for the well-being of humanity.


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