Washington: Buildings destroyed by the 2011 Tohoku earthquake released thousands of tonnes of climate-warming and ozone-depleting chemicals into the atmosphere, finds a new study.
The new study suggests that the thousands of buildings destroyed and damaged during the 9.0 magnitude earthquake and tsunami that struck Japan four years ago released 6,600 tonnes of gases stored in insulation, appliances and other equipment into the atmosphere.
Emissions of these chemicals, called halocarbons, increased by 21 percent to 91 percent over typical levels, according to the study slated to be published in Geophysical Research Letters.
"What we found is a new mechanism of halocarbon emissions coming from the earthquake," said Takuya Saito, a senior researcher at the National Institute for Environmental Studies in Tsukuba, Japan, and lead author of the study.
The study is the first to examine emissions of these gases following a natural disaster.
Halocarbons released as a result of the earthquake include chemicals that deplete the ozone layer and contribute to global warming -- including some gases that are no longer used.
These include chlorofluorocarbons like CFC-11, a powerful ozone-depleting chemical used in foam insulation until it was phased out in 1996, and hydrochlorofluorocarbons like HCFC-22, an ozone-depleting refrigerant which is in the process of being phased out.
Among other halocarbons released by the earthquake were hydrofluorocarbons, or HFCs, and sulfur hexafluoride -- both potent greenhouse gases.
The emissions of the six halocarbons released from Japan in 2011 are equivalent to the discharge of 1,300 tonnes of CFC-11 alone, revealed the research.
The total emissions of the six chemicals are also equivalent to the release of 19.2 million tonnes of carbon dioxide into the atmosphere, according to authors.