Experimental data: measurement campaign Hintereisferner Experiment, HEFEX.

The HEFEX micrometeorological measurement campaign was conducted during three weeks in August 2018. Measurement towers were installed on the 1. and 2. August and removed on 22. August. The measurement network consisted of five 3-m tripod towers  located at an along- and an across-glacier transect to capture the spatial variations of the atmospheric flow system at the glacier and associated heat exchange processes. The across-glacier transect consisted of three turbulence towers installed from the peripheral zones of the glacier towards the centreline. The location of the across-glacier transect coincides with where the valley of Langtaufererjochferner discharges into the valley of the Hintereisferner glacier. In this area, thermal flows from the surrounding area were hypothesized to influence the surface of Hintereisferner. All stations were installed at comparatively flat areas of the glacier with slope angles varying between 6 and 8°. Measurement towers were installed directly at the ice surface. Due to pronounced changes in the ice surface caused by strong ice melt during the measurement campaign, frequent visual inspection and small adjustments to the location of the towers were essential for good data quality. This mainly consisted of repositioning the tower feet to ensure the tower stability and re-levelling the sensors. Post-processing of data, i.e. correction of data for height changes and rotation of the mast further ensured data quality