The butterfly effect of shale gas
From an observation station located in Switzerland, researchers from the InfraRed Group of Atmospheric and Solar Physics of the University of Liege have identified a potentially worrying phenomenon that could lead to air quality degradation: since 2009, the level of ethane in the atmosphere has increased by 5% per year while previously, it was decreasing by 1%. The explanation for this increase can be found several thousand kilometers away in the United States where the massive exploitation of shale gas contained underground is certainly not without consequences.
At the summit of Jungfraujoch
Amazingly, this leaking of ethane was not identified in the US but from the snow-capped summits of the Jungfraujoch station, in the middle of the Swiss Alps. The station is an international scientific observatory which is also home to the Laboratory of Atmospheric and Solar Physics of ULg among others. It is here that measurements of infrared radiation were carried out at high altitude in order to avoid interference from water which is abundant in the lower layers of the atmosphere and which could interfere with the results.
Watch out for bad ozone
Ethane should not be taken lightly! While this gas is not polluting in itself, its degradation makes it dangerous. It ends up by forming ozone in the troposphere. This is “bad” ozone which is found nearer to ground level and reaching a height of ten kilometers. It is a major pollutant for human beings and the biosphere which is the exact opposite of “good” ozone present at higher altitudes and protecting us from the sun’s ultraviolet rays. “It is due to this bad ozone that there are sometimes pollution-alert days in summer when people are advised not to practise sport or to go outside if they are suffering from asthma… It is also an oxidant which is dangerous for vegetation and construction materials (roofs, chassis etc.)”, Explains Emmanuel Mahieu. More seriously still, ethane is emitted at the same time as methane, a more efficient greenhouse gas than CO2.