Washington: It is emerging that the so-called hydrofluorocarbons (HFCs), a class of widely used chemical coolants, cause the far greater destruction of the ozone layer than previously thought. NASA says in a new study that HFCs will cause 0.035% depletion of the protective layer that shields the Earth’s surface from the harmful rays of the sun, ozone by 2050. Previously, scientists viewed the HFCs contribution as negligible to degradation of the ozone.
The ozone layer is made up of molecules capable of absorbing sun’s harmful radiation to prevent it from reaching the surface of the earth.
According to the space agency NASA, HFCs cause small but measurable adverse impact on the ozone. NASA estimates that HFCs will contribute to depletion of the ozone by 0.035% in the next 35 years.
How HFCs Cause Ozone Degradation?
NASA says that HFCs cause the destruction of the ozone in more than one way. In one instance, the space agency says that HFC emissions escalate warming of the stratosphere, thus catalyzing chemical reactions that cause the destruction of ozone molecules.
Another way in which HFC contributes to ozone degradation is that they speed up the upward movement of air that is ozone-poor. The latter contribution is more profound in the tropics.
Previously, classes of chemicals called hydrochlorofluorocarbons (HCFC) and chlorofluorocarbons (CFC) were widely used as coolants in homes and automobiles cooling. However, they have since been replaced by HFCs, which were considered to be less destructive to the ozone.
NASA’s new findings show that HFCs aren’t as more dangerous on the ozone as the previous coolants, their contribution to depletion of the protective blanket is not as small as previously known. HFC emissions have a linear impact on ozone change, reducing emissions by 50% will result in depletion of ozone being reduced by the same percentage.
It is hoped that the new NASA finding of HFCs and their impact on ozone will help inform the formulation of more robust environmental policies.
NASA’s finding of HFCs was published in the journal called Geophysical Research Letters.