2021 Sixth Warmest Year

• 19 Jan 2022

For Prelims: La Niña, wildfires, Intergovernmental Panel on Climate Change (IPCC), Heatwaves, South West Monsoon

For Mains: Rising Temperature of Earth and its impact, Steps taken in this direction

Why in News

Recently, two American agencies have released data showing that 2021 was the world’s sixth warmest year on record.

• And the last 10 years were the warmest since record-keeping began in 1880.
• The data was collected by the US. space agency NASA and the National Oceanic and Atmospheric Administration (NOAA).

Key Points

• Earth in 2021:
  • Earth in 2021 was about 1.1 degrees Celsius warmer than the late 19^th century average, the start of the industrial revolution.
• Northern and Southern Hemisphere:
  • The Northern Hemisphere land surface temperature was the third highest on record — 2016 (second) and 2020 (first) were warmer.
  • The 2021 Southern Hemisphere surface temperature was the ninth highest on record.
• Sea Surface Temperatures:
  • Record-high sea surface temperatures were observed across parts of the Atlantic and Pacific oceans.
  • The upper ocean heat content was record high in 2021, surpassing the previous record set in 2020.
  • The seven highest ocean heat content have all occurred in the last seven years (2015-2021).
• Antarctic Sea:
  • Antarctic sea ice extent during December 2021 was 3.55 million square miles.
  • This value is 11.6% below average and was the third-smallest December extent on record.
  • Only December of 2016 and 2018 had a smaller extent.
• Effects of La Niña:
  • Effects of La Niña kept world temperatures lower.
    • La Niña is a weather pattern that happens in the Pacific Ocean but affects weather around the world.
    • A La Niña event happens when ocean surface waters cool along the Pacific coast of the South American tropics. This takes place about every two to seven years.
• Reasons for the Warming Trend:
  • This warming trend around the globe is due to human activities that have increased emissions of carbon dioxide and other greenhouse gases into the atmosphere.
    • The planet is already seeing the effects of global warming: Arctic sea ice is declining, sea levels are rising, wildfires are becoming more severe and animal migration patterns are shifting.

Rising Temperature in India

• The Intergovernmental Panel on Climate Change (IPCC) released the first part of its Sixth Assessment Report (AR6) titled Climate Change 2021: The Physical Science Basis in August, 2021.
• Indian Sub-continent Specific Findings:
  • Heatwaves: Heatwaves and humid heat stress will be more intense and frequent during the 21^st century over South Asia.
  • Monsoon: Changes in monsoon precipitation are also expected, with both annual and summer monsoon precipitation projected to increase.
    • The South West Monsoon has declined over the past few decades because of the increase of aerosols, but once this reduces, the country will experience heavy monsoon rainfall.
  • Sea Temperature: The Indian Ocean, which includes the Arabian Sea and Bay of Bengal, has warmed faster than the global average.
    • The sea surface temperature over the Indian ocean is likely to increase by 1 to 2 °C when there is 1.5°C to 2°C global warming.
• Recent Climate Related Measures by India:
  • An ambitious climate action vision with five elements has been unveiled at UNFCCC COP26.
    • Taking non-fossil energy capacity to 500 GW by 2030.
    • Meeting 50% of energy requirements from renewable energy by 2030.
    • Reducing total projected carbon emissions by one billion tons by 2030.
    • Reducing the carbon intensity of the economy to less than 45% by 2030.
    • Achieving the target of “net zero” by 2070.
  • India now ranks fourth in terms of installed renewable energy capacity and non-fossil energy has increased by more than 25% in the past seven years and reached 40% of the total energy mix.
  • India has also taken the lead in initiatives such as the International Solar Alliance (ISA) and Coalition for Disaster Resilient Infrastructure (CDRI).

Source: DTE