Carbon dioxide as indicator of the greenhouse gas effect:
- The rapidly rising concentration of carbon dioxide in the atmosphere is one of the best indicators of the manner in which the planet has been warming up.
- The higher the concentration of carbon dioxide, the greater the greenhouse gas effect that causes the Earth’s atmosphere to heat up.
Trends:
- When direct measurements began at the Mouna Loa observatory in 1958, concentrations were around 315 ppm.
- Currently, the carbon dioxide concentration is growing at more than 2 ppm per year, and scientists say the growth rate is likely to reach 3 ppm a year from this year.
Reason for increasing concentration:
- The increase in atmospheric concentrations is caused by the carbon dioxide being constantly emitted in different, mostly man-made, processes.
- In recent years, the growth in global carbon dioxide emissions has slowed down considerably. However, the rapid rise in the atmospheric concentrations is due to the fact that carbon dioxide has a very long lifespan in the atmosphere, between 100 and 300 years.
The 2ºC equivalence:
- The global target is to keep the rise in average surface temperatures below 2ºC higher than during pre-industrial times, and if possible below 1.5°C.
- The carbon dioxide concentration level corresponding to a 2ºC rise in global temperatures is generally understood to be 450 ppm. At current rates of growth, that level would be reached in less than 12 years, that is by 2030.
