Great! But what does this mean? In short it means that the two process are potentially linked over these timescales, which could implicate that gas emissions are driving seismicity (I am sure there are other possibilities though...). It confirms that volcanoes such as Etna are very dynamic and that sub-surface processes (which almost inevitably cause these fluctuations) rapidly alter the gas emissions that are recorded at the surface (or vice-versa). This is where my PhD research kicks in, why are we seeing these changes over these timescales? What is causing these very periodic structures? Of course this trend in emissions is not just seen at Etna but at other volcanoes worldwide. It could therefore be important for understanding the state of shallow magma pathways and storage areas in basaltic systems generally.