The Greenland Ecosystem Monitoring Program has maintained a mooring in Young Sound -Tyrolerfjord, approximately 15 km from the outer sill (74.322° N, 20.269° W). This mooring has been serviced and re-deployed every August from 2003 to 2015. mZERO was equipped with a CTD (Sea-Bird SBE37SMP). The mean sensor depth was ~ 63 m depth (+/- 2.7 m; range: 69 m (2008-2009) - 62 m (2009-2010; 2012-2013)). The CTD sampling interval varied between 15 and 20 min (2003-2009) to 10 min (2009-2015). Data gaps exist due to mooring malfunction, or when redeployment was hampered by ice conditions. Accuracy of the temperature and conductivity sensor is ±0.002 °C and ± 0.0003 S m-1, respectively. Water column:Water column MarineBasis Zackenberg:The MarineBasis programme collects physical, chemical and biological data from the Greenland coastal zone. Work is focused in two fjord systems (Godthåbsfjord and Young Sund) both influenced by glaciers connected to the Greenland Ice Sheet.