IAS Gyan

Daily News Analysis

How global warming might affect food security

19th October, 2020 Environment

Context: Alarm call: Scientists warn higher temperatures during the ‘growing season’ in the tropics and sub-tropic regions will greatly affect crop productivity. 


  • Between the year 1870 (the first industrial revolution) and today, the global temperature has risen by almost 2 degrees Celsius.
  • This has come about due to more fossil burning (oil, natural gas, coal), which has also increased the carbon dioxide (abbreviated as CO2) levels from 280 ppm to 400 ppm.
  • This heating has caused glaciers (and snow capping mountains) to melt and the sea level to rise.
  • The October 2 issue of National Geographic Magazine warns that the glaciers in Garhwal, Uttarakhand may virtually disappear by 2035.

Ocean acidification

  • The rise in CO2 levels has also acidified the ocean, leading to weakening the shells and skeletons of animals living in the sea, climate.org.
  • On land, the rise in CO2 levels has both positive and negative effects.
  • This being a ‘Green House Gas’, it traps the Sun’s heat from the atmosphere and warms the temperature, aids in the photosynthesis of plants, making them grow more, but at the same time restricts the plant’s ability to absorb nitrogen, thus restricting crop growth.

How will this CO2 level heating affect food security in the coming years?

  • Higher temperatures during the ‘growing season’ in the tropics and sub-tropic regions (India and our neighbours, Saharan and Sub-Saharan Africa and parts of South America) will greatly affect crop productivity, and that this would be the ‘norm’.
  • Given this double whammy of affecting ocean life and food security.