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)

In the years 2009-2019, 49 samplings (shallow drilling or snowpits) were made on the glacier during the spring measurement campaigns in order to determine the bulk snow density and SWE. The average density of snow cover ranges from 386 to 447 kg/m3. The dataset includes part of the results from the project “Hindcasting and projections of hydro-climatic conditions of Southern 350 Spitsbergen” (grant no. 2017/27/B/ST10/01269) financed by the Polish National Science Centre, “Arctic climate system study of ocean, sea ice, and glaciers interactions in Svalbard area”—AWAKE2 (Pol-Nor/198675/ 17/2013), supported by the National Centre for Research and Development within the Polish–Norwegian Research Cooperation Programme and the SvalGlac—Sensitivity of Svalbard glaciers to climate change, the ESF Project, the project Integrated Arctic 355 Observing System (INTAROS)- Horizon 2020, the ice2sea 7th FP projects. The studies were carried out as part of the scientific activity of the Centre for Polar Studies (University of Silesia in Katowice) with the use of research and logistic equipment of the Polar Laboratory of the University of Silesia in Katowice.

1. Dataset of UAV vertical aerial photos of front and ice melange in the north part of Tunabreen, obtained in spring 2017. Area covered: ~1600x~800m. Used UAV: Phantom 3 Advanced, flight height: 100m. Data obtained during fieldwork supported by Svalbard Science Forum, Arctic Field Grant 2017 with cooperation with University of Maine (USA) and the University Centre in Svalbard (Norway).

Time-lapse cameras In order to determine the state of coverage of the area, e.g. period of snow cover on a tundra, the extent of the glacier front, etc., it is necessary to perform photographic imaging at a specific time interval. This will allow for precise diagnosis of snow conditions. The camera is installed at the main entrance to the NCU Polar Station. The lens is pointed in a westerly direction, towards Prins Karls Forland 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)

Glacier velocities are derived from the displacements of stakes installed close to the front of Hansbreen. Measurements of stakes position were conducted in 2008-2009, 2010-2011, 2013-2014 and 2015, with precise dGPS receiver (Leica 1230, accuracy ±5cm) and with time intervals from 3 hours to a few days.

Hansbreen velocity is measured with a Global Navigation Satellite Systems (GNSS) receiver that sampled location every 3 hours at stake 4MONIT located approximately 3.5 km upstream of the glacier terminus (N77°02’ E15°28’). Monitoring of the glacier is conducted by Institute of Geophysics Polish Academy of Science. We calculate the daily speed based on each midnight positions (with a horizontal accuracy of ±4 cm).

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

Dataset contains results of GPR survey performed with 800 MHz antennas for snow depth calculation. Fieldwork has been done during peak of accumulation, along repeated profiles on several glaciers in the region of Hornsund, Svalbard: Amundsenisen (2013) Werenskioldbreen (2013, 2014, 2015) Nannbreen (2013) Ariebreen (2014) Flatbreen (2018) Storbreen (2018) 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); References: 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

Englacial water pressure was recorded by placing HOBO 250-Foot Depth Water Level Data Loggers in the center of Crystal Cave (N77°02' E15°34', 174 m) channel system (Hansbreen glacier). Data loggers were set to record values every 30 minutes, resampled to daily in post-processing, and have a resolution of 2.55 kPa for a typical error of 3.8 cm water level. Water pressure was converted in water level. Sensor was placed in the cave by drilling anchor points into the ice above a vertical shaft, then hanging cables down in the center of conduit. Stabilization cables were used to keep sensors from attaching to and freezing into ice walls by manually rappelling down to the sensor and attaching it to three horizontal cables, anchored into the ice walls at about 120 degrees apart. Senor was installed in Crystal Cave at about 100 m total distance from the cave entrance, in ice about 74 m thick. The sensor was installed 28 m above the glacier bed and 46 m below the ice surface.

Downwelling shortwave flux in air measurements from AWS located on the Werenskioldbreen. The sensors are installed on a mast that is mounted in the glacier ice. During the season, the distance between the glacier's surface and the sensors increases. The station is serviced at least once a year between March and April.