Atmospheric Carbon Dioxide Will Continue to Warm Earth For Centuries

Even if we attain zero carbon dioxide emission, the rise in the temperatures will continue, according to a new study.

The study, led by researchers at the Princeton University states that Earth's atmosphere will continue to warm our planet for the next hundreds of years even if carbon dioxide emission is curbed.

To prove this, the researchers simulated an Earth on which they stopped the carbon dioxide emission soon after 1,800 billion tons of carbon entered the atmosphere. The results of the computer model revealed that within 20 years almost 40 percent of the carbon was absorbed by the Earth's oceans and landmasses and 60 percent of the carbon within 100 years and 80 percent within 1,000 years.

According to theories a drop in the atmospheric carbon dioxide should have a cooling effect, but these overlooked the fact that oceans take in lesser heat over the years.

"Scientists have thought that the temperature stays constant or declines once emissions stop, but now we show that the possibility of a temperature increase cannot be excluded," said Frolicher, now a researcher at the Swiss Federal Institute of Technology in Zurich, in a statement. "This is illustrative of how difficult it may be to reverse climate change - we stop the emissions, but still get an increase in the global mean temperature."

In the studies conducted earlier, the researchers argued that a sudden stop in carbon emission would lead to decline or steadiness in the global temperature. But the researchers failed to include the fact that even oceans absorb less heat over time.

The gas that is not absorbed by the oceans remains in the atmosphere due to which there is no reduction in the global temperature.

As the ocean absorbed less and less heat it was seen that the planet warmed by 0.37 degree Celsius during the next 400 years. Though the amount is small, the heat continues to exist. Since the pre-industrial times the Earth has warmed by 0.85 degree Celsius.

According to estimates of the Intergovernmental Panel on Climate Change, a global temperature spike of 2 degree Celsius compared to the pre-industrial levels would interfere with the climate change on a larger scale. This can be avoided when humans make an effort to maintain the cumulative carbon dioxide emission lesser than 1,000 billion tons of carbon.

Frolicher says, "If our results are correct, the total carbon emissions required to stay below 2 degrees of warming would have to be three-quarters of previous estimates, only 750 billion tons instead of 1,000 billion tons of carbon. Thus, limiting the warming to 2 degrees would require keeping future cumulative carbon emissions below 250 billion tons, only half of the already emitted amount of 500 billion tons."

The findings were documented in Nature Climate Change.