is able to be explained through the presence of hotspots. However, the volcanic systems are not always connected since the magma pathways open and close. For example, the Shinmoedake vertical connection was closed for approximately 300 years until reactivation. The changes in volume for the Aira and Kirishima systems suggest they had different inflation and deflation periods. Between 2009 and 2013, there was evidence of inflation in the Aira system. However, after the 2011 eruption at Kirishima, the Aira system experienced a deflation. This was Aira caldera's only deflation between 2009 and 2013. Inflation of Aira Caldera The magma storage underlying Aira Caldera has been feeding into the stratovolcano Sakurajima, expanding over time. However, there have been points in time where the chamber has deflated as a result of eruptions releasing the pressure built which cannot be explained by stress changes. Thus, it has been described as a consequence of magma withdrawing from the Aira system when Kirishima was replenishing. A prime example is the Sakurajima eruption in 1914 (approximately 1.5km3 in volume), which caused the magma chamber to sink 60cm. 58 people were killed in the eruption. For this amount of magma to erupt, it would take approximately 130 years for the chamber to refill as according to Dr James Hickey and his co-authors. Dr Hickey stated "These results were made possible by combining data from various monitoring methods and applying them to new numerical modelling techniques, moving away from older modelling methods that have been in use since the 1950s." Nevertheless, there are continuous measurements of the ground movement that indicate the area is now inflating. Recent GPS deformation measurements, amalgamated with geophysical data and computer modelling enable the reconstruction of the magma system beneath the caldera. Through this, Dr James Hickey and his co-authors were able to create a depiction of the tunnels beneath the caldera. They discovered that magma is filling the magma chamber at a faster rate than the Sakurajima volcano erupts. The reservoir is expanding each year as a volume of 14 million m3 is supplied to the system. Dr Haruhisa Nakamichi, Associate Professor at the Disaster Prevention Research Institute, Kyoto University, and co-author, said: "It is already passed by 100 years since the 1914 eruption, less than 30 years is left until a next expected big eruption, Kagoshima city office has prepared new evacuation plans from Sakurajima, after experiences of evacuation of the