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.

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

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.

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. Site Information The borehole near the UMK station in Kaffioyra was located at the existing meteorological garden, about 100 m from the shoreline. The drilling was carried out on 20-21.07.2023. The substrate is dominated by loose sandy-gravel beach sediments. A large amount of fine material and the formation of a core in a small part of the hole made it possible to reach a depth of 10.0 m below sea level. 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)

• Discharge measurements were conducted from May/June/July to September/October in the years 2007–2012. Direct observation periods were 62, 51, 61, 40, 121, and 35 days in the consecutive years. The data set was obtained from CTD-DIVER DI 261 or Mini-Diver (Van Essen Instruments, Delft, The Netherlands) logger with barometric compensation by BaroDiver (Schlumberger, Houston, TX, USA) with 10-min intervals and flow velocities were measured with a SEBA F1 current meter (SEBA Hydrometrie GmbH, Kaufbeuren, Germany). Mean daily discharge and total runoff in the hydrologically active season was calculated on the basis of the 24h running average of the water level and a rating curve (Appendix 1). More details have been reported by Majchrowska E., Ignatiuk D., Jania J., Marszałek H., Wąsik M., 2015: Seasonal and interannual variability in runoff from the Werenskioldbreen catchment, Spitsbergen. Polish Polar Research vol. 36, no. 3, pp. 197–224. doi: 10.1515/popore−2015−0014 • Hydrological data for Werenskioldbreen - archive of the University of Silesia. The base contain mean daily discharge in the years: 1972, 1973, 1974, 1979, 1980, 1983, 1985, 1986, 1988, 1998, 2007, 2008, 2009, 2010, 2011, 2012, 2013, 2017 (18 hydrologically active seasons) – Appendix 2

Dataset contains snowpack density derived from shallow snow cores. Fieldwork has been done during peak of accumulation on several glaciers in the region of Hornsund, Svalbard: Amundsenisen (2013) Werenskioldbreen (2013, 2015) Nannbreen (2013) Flatbreen (2013, 2018) Storbreen (2013, 2018) Results might be valuable i.a. for mass-balance estimations or GPR survey validation. Acknowledgements: Research Council of Norway, Arctic Field Grant 2013: Spatial distribution of snow cover and drainage systems on the glaciers on Wedel Jarlsberg Land (RiS ID: 6158); the National Science Centre PRELUDIUM 4: Role of meltwater from snow cover for supplying drainage systems of the Spitsbergen glaciers (2012/07/N/ST10/03784); Citation: LASKA M.,GRABIEC M.,IGNATIUK D.,BUDZIK T.,2017. Snow deposition patterns on southern Spitsbergen glaciers, Svalbard, in relation to recent meteorological conditions and local topography. Geografiska Annaler, Series A: Physical Geography, 99(3): 262–287. doi:10.1080/04353676.2017.1327321