Unusual Arctic warming explained by overlooked greenhouse gases

The same gases that caused holes in Earth’s ozone layer in the past century are responsible for the rapid warming of the Arctic as well, according to a new study published in Nature . Scientists looked at the effect of these gases in climate simulations between 1955 and 2005. They found that the gases accounted for up to half of the warming and sea-ice loss of the Arctic during that period, Nature reports. These so-called ozone-depleting substances (ODSs) are considered potent greenhouse gases and include organic chlorine and bromine compounds such as chlorofluorocarbons. The researchers also concluded that the warming was caused directly by the gases and not because of their interactions with the ozone layer. ODSs in the atmosphere are declining since they were banned in the 1980s, following concerns over the ozone layer hole over Antarctica. Scientists would need to replicate these findings in order to explore the contribution of ODSs to global warming during the past decades.