Carbon dioxide levels and Global Warming

The global concentrations of carbon dioxide in the atmosphere are at dangerously higher levels. The higher the concentration of carbon dioxide, the greater the greenhouse gas which causes the Earth’s atmosphere to heat up. Hence the levels of carbon dioxide are one of the best indicators of the manner in which the planet has been warming up.

Why Carbon dioxide levels are increasing?

  • The increase in levels of carbon dioxide is attributed to different, mostly man-made, processes.
  • The increased in the concentration of carbon dioxide is also attributed to the fact that carbon dioxide has a very long lifespan in the atmosphere, between 100 and 300 years. Hence even if the emissions were to miraculously reduce to zero all of a sudden it would have no impact on the atmospheric concentrations in the near term.
  • Almost half of the emitted carbon dioxide is absorbed by plants and oceans, leaving the other half to go into the atmosphere. An addition of about 7.5 billion tonnes of carbon dioxide to the atmosphere leads to a 1 ppm rise in its atmospheric concentration.
  • It is estimated that in 2018 about 18.6 billion tonnes of carbon dioxide, would have been added to the atmosphere, leading to rising of 2.48 ppm in atmospheric concentrations.

Carbon dioxide and Global Warming

The carbon dioxide concentration level corresponding to a 2ºC rise in global temperatures target set under Paris climate deal is generally understood to be 450 ppm (it is now around  415). With the current trends that levels would be reached in less than 12 years that is by 2030.

The report of the Intergovernmental Panel on Climate Change has stressed on the need to achieve net zero emissions of all greenhouse gases, not just carbon dioxide, by 2050 to keep alive any realistic chances of restraining the temperature rise to within 1.5ºC. The net zero needs to be achieved by 2075 to attain the 2ºC target.