The database contains irregular meteorological data collected from the Hans Glacier (Hansbreen) in the years 2007-2017 as part of the polar expeditions of the University of Silesia in Spitsbergen / Svalbard. Data from three automatic weather stations. Measured elements: air temperature, air humidity, wind direction, wind speed, elements of radiation balance, others.

Bathymetry at the front of tidewater glaciers derived from different sources. Bathymetry data in Hansbukta and Burgerbukta have been collected by the Norwegian Hydrographic Service using a multi-beam survey during 2007–2008. Later measurements in Hansbukta were collected with single beam profiling at the Hansbreen front in 2015. Data format: grid (6m), UTM 33X. Single echo-sounding data collected during summer 2011, by the University of Silesia.

Permafrost monitoring System of thermistors (temperature strings with loggers) to monitor the ground thermal state Precise data on the thermal state of the frozen ground is one of the key missing components of the environmental monitoring at the research stations spread across Spitsbergen. The CRIOS project will allow us to equip the newly established borehole with precise temperature strings that will record ground thermal changes over the next couple of years. A system of temperature strings will be used in the monitoring of the thermal state of permafrost in drilled boreholes. Devices were tested in severe weather and are commonly used for permafrost monitoring by other research groups working in polar regions. The hole in the vicinity of the UAM station in Petuniabukta was delineated at a distance of about 50 m from the shoreline, in the zone between the Polish and Czech stations. The drilling was carried out on 22-23.07.2023. The bedrock is built up by siltstone and sandstone. At the drilling site, they are covered by thick-bedded beach sediments. During the drilling, a depth of 7 meters below sea level was reached, and with no further drilling progress, a decision was made to install a string to the depth obtained. CRIOS – Cryosphere Integrated Observation Network on Svalbard Project financed from the EEA Financial Mechanism 2014-2021 operated by the National Science Centre in Poland Agreement no. UMO-2022/43/7/ST10/00001 to a predefined project no. 2022/43/7/ST10/00001 Project period: 08.09.2022 - 30.04.2024 (2029)

Radar satellite (SAR) images for Hornsund: ERS-1, ERS-2, ENVISAT, ALOS Palsar, TerraSAR-X, TandemX-1, acquired between 1992 and 2014. 210 archival SAR data were provided at the SLC level, so that both radiometric and geometric corrections were applied using the same methods, and with the same digital elevation model (2008 DEM SPOT developed by the IPY-SPIRIT Project; Korona et al., 2009). The SAR data were processed in BEAM (http://www.brockmann-consult.de/cms/web/beam).

1. Two high-quality UAV movies taken in Hornsund fiord on 15th Sep 2016 with Phantom 3 Advanced usage. The movies are focused on Horyzont II ship during unloading goods to the Polish Polar Station Hornsund. Format file: .MOV. 2. Dataset consist six UAV movies taken in neighborhood of stake no. 4 of Hansbreen, one taken in the vicinty of stake no. 6 of Hansbreen and two on Tuvbreen. The movies from stake no. 4 show the ablation zone, crevasses, glaciers in the area and a team of University of Silesia scientists during maintanance of automatic weather station (AWS). The movie from stake no. 6 presents the surface of Hansbreen towards accumulation zone. The movies from Tuvbreen show the area around, surface of the glacier and University of Silesia team. UAV: Phantom 3 Advanced. Format file: .MOV. 3. One high-quality UAV movie taken from West morain of Paierbreen 22nd Aug 2016 with Phantom 3 Advanced usage. The movie is focused on the front of Paierlbreen. Format file: .MOV. 4. Two high-quality UAV movies taken on Silesiabreen 23nd Aug 2016 with Phantom 3 Advanced usage. The movie is focused on the snowline of Silesiabreen, University of Silesia scietists while fieldwork and neighbourhood. 5. UAV movie of Storbreen upper ablation area in 21st Aug 2016. 6. Three high-quality UAV movies taken from vicinity of Treskelen in Hornsund on 12 Sep 2016 with Phantom 3 Advanced usage. The movies are focused on the University of Silesia team during automatic weather station maintanance, sailing boat operated by scientists and Hornsund fiord. 7. A high-quality UAV movie taken from vicinity of Brateggbreen on 5 Sep 2016 with Phantom 3 Advanced usage. The movie is focused on Brateggbreen front and its proglacial lake. Format file: .MOV. 8. UAV movies of Werenskoildbreen front and morain in summer 2016

Results of supervised classification of six Landsat 8 images acquired on: 25 May, 3 June, 22 June, 15 July, 4 August and 20 August 2014, covering glaciers in Hornsund fiord. Method of classification: Maximum Likelihood. The results show variability of snow cover areas in melting period of 2014 for glaciers located in Hornsund fiord and larger than 9 km2 (Körberbreen, Samarinbreen, Chomjakovbreen, Mendelejevbreen, Svalisbreen, Hornbreen, Storbreen, Kvalfangarbreen, Mühlbacherbreen, Paierlbreen and Hansbreen). For more information, please check: https://doi.org/10.3390/w9100804 Overview: Results of Maximum Likelihood classification of Landsat 8 images for analysed glaciers. Red - snow cover, yellow - glacier ice, black - debirs, grey - cloud cover.

Thermal structure of selected S Spitsbergen glaciers was derived from ground based radio-echo sounding (RES). The division between cold and temperate ice layers is based on indirect interpretation of GPR (ground penetrating radar) image. Cold ice layer is virtually “transparent” for radio waves, while temperate ice layer is characterised by numerous diffractions on water inclusions. The database contains results from 479.7 km of RES profiles acquired in 2007-2014 on 12 glaciers in Wedel Jarlsberg Land and Torell Land (S Spitsbergen) including: Amundsenisen, Austre Torellbreen, Vestre Torellbreen, Hansbreen, Storbreen, Hornbreen, Hambergbreen, Recherchebreen, Scottbreen, Renardbreen, Werenskioldbreen and Ariebreen. Basic characteristics of investigated glaciers and its thermal structure is provided in table 1 (supplementary information). The surveys used GPR antennas in range 25-200 MHz, selected according to expected ice depth. Thanks to that on 87% of the profiles ice/bed interface has been identified. The radar system was pulled behind the snowmobile moving with velocity c. 20 km h-1. Applying trace interval 0.2-1.0 s, trace-to-trace distance was in range 1-5m. Trace positions were acquired by GNSS receivers working in navigation or differential mode with respective accuracy 3.0 m and 0.1m. RES data were processed applying standard filtering procedure (DC-offset, time-zero adjustment, 2-D filter, amplitude correction and bandpass filtering). Time-to-depth conversion used average radio wave velocity (RWV) for glacier ice 16.4 cm ns-1, 16.7 and 16.1 for cold and temperate ice respectively, based on CMP survey. More precise description of data collection, processing and quality is provided by Grabiec (2017). In S Spitsbergen polythermal glaciers are predominant. 57.8% of surveyed profiles consist of both: temperate and cold ice layers; 22.7% profiles is entirely temperate while 6.6% contains cold ice only (remaining profiles have undefined thermal structure). Studied glaciers represent broad spectrum of polythermal structure with cold-to-temperate ice ratio from 99:1% (Ariebreen) to 2:98% (accumulation zone of Vestre Torellbreen). The data were collected and processed under following projects: • IPY/269/2006 GLACIODYN The dynamic response of Arctic glaciers to global warming • UE FP7-ENV-2008-1 ice2sea Estimating the future contribution of continental ice to sea-level rise • PNRF-22-AI-1/07 AWAKE Arctic Climate and Environment of the Nordic Seas and the Svalbard – Greenland Area • NCBiR/PolarCLIMATE-2009/2-1/2010 SvalGlac Sensitivity of Svalbard glaciers to climate change • Pol-Nor/198675/17/2013 AWAKE-2 Arctic climate system study of ocean, sea ice and glaciers interactions in Svalbard area • 03/KNOW2/2014 KNOW Leading National Research Centre Reference: Grabiec M. 2017: Stan i współczesne zmiany systemów lodowcowych południowego Spitsbergenu w świetle badań metodami radarowymi. Wydawnictwo Uniwersytetu Śląskiego, 328 s.

Subglacial topography was derived from radio-echo sounding (RES) survey conducted in spring 2008 by the University of Silesia research team (M. Grabiec and J. Jania) in cooperation with the Institute of Geophysics Polish Academy of Sciences (D. Puczko) and the Maria Curie-Sklodowska University (G.Gajek). The profiles were acquired by the radar system equipped with 25 MHz unshielded antenna pulled behind snowmobile. Traces were recorded every 0.5 s, that translates into 1.5-2.0 trace-to-trace distance depending on the vehicle’s velocity. Traces were positioned by GNSS receiver working in differential mode with 3D accuracy ± 1m. In total over 100 km of RES profiles were acquired on Hansbreen, 66 km on Werenskioldbreen and 43 km on Renardbreen. RES data were processed using standard procedure including: DC-offset, time-zero adjustment, 2-D filter, amplitude correction, bandpass filtering and migration. Time-to-depth conversion applied average radio-wave velocity in glacier ice 16.4 cm ns-1 calculated based on CMP analysis performed on Hansbreen in the same season as the GPR profiling. The ice/bed interface was picked up semi-automatically with RMSE 5.3 ns (0.43 m) (Grabiec, 2017). Then the bedrock elevation data were interpolated over studied glaciers taking into account elevation of nonglaciated surroundings (Grabiec 2017) and bathymetry at the front of tidewater Hansbreen (Grabiec et al. 2012). Finally produced 100 m resolution DEMs are in UTM 33X WGS84 reference system. DEM of 300 m resolution is freely available. For 100 m resolution DEM please contact: mariusz.grabiec@us.edu.pl. The data were collected and processed under following projects: • IPY/269/2006 GLACIODYN The dynamic response of Arctic glaciers to global warming • UE FP7-ENV-2008-1 ice2sea Estimating the future contribution of continental ice to sea-level rise • PNRF-22-AI-1/07 AWAKE Arctic Climate and Environment of the Nordic Seas and the Svalbard – Greenland Area • 03/KNOW2/2014 KNOW Leading National Research Centre Reference: Grabiec M., Jania J., Puczko D., Kolondra L., and Budzik T., 2012: Surface and bed morphology of Hansbreen, a tidewater glacier in Spitsbergen. Polish Polar Research 38(2): 111-138. Grabiec M. 2017: Stan i współczesne zmiany systemów lodowcowych południowego Spitsbergenu w świetle badań metodami radarowymi. Wydawnictwo Uniwersytetu Śląskiego, 328 s. Decaux, L., Grabiec, M., Ignatiuk, D., and Jania, J. 2018: Role of discrete recharge from the supraglacial drainage system for modelling of subglacial conduits pattern of Svalbard polythermal glaciers, The Cryosphere Discuss., https://doi.org/10.5194/tc-2017-219, in review.

Inventory of tidewater glaciers delineated from archival satellite images (Aster, Landsat) acquired in the period 1999-2006. Shapefiles have basic information in the attribute table (name, ID, area, length, front type of tidewater glaciers). When a tidewater glacier has a compound basin, only that part of it feeding the calving front was taken into consideration and presented here as the tidewater glacier. This implies that tributary glaciers clearly separated from the main basin by moraines are not included in the database. Similarly, marginal sections of tidewater glaciers that terminate on land are not included in the Inventory. Detailed description of the source data and accuracy can be found in: Błaszczyk M., Jania J., Hagen J.O. 2009: Tidewater glaciers of Svalbard: Recent changes and estimates of calving fluxes. Polish Polar Research, 30(2): 85-142. http://www.polish.polar.pan.pl/ppr30/PPR30-085.pdf

Meteorological data from Flat Glacier (Flatbreen) - air temperature.