The positions of the glacier termini in Hornsund are derived with very high frequency in the period 1991–2018. Over 230 multispectral and Synthetic Aperture Radar (SAR) data were used: LANDSAT 5, LANDSAT 7, LANDSAT 8, Terra ASTER, Alos AVNIR, SPOT 5, ERS-1, ERS-2, ENVISAT, Alos PALSAR, TerraSAR-X, TanDEM-X, and Sentinel-1. SAR data were used to detect any variability in the glacier front during the polar night. The satellite data were digitized manually to obtain the ice cliff position. Multispectral images were orthorectified and geocoded in PCI Geomatica and ArcGIS software. SAR data were usually provided at the SLC level, so that both radiometric and geometric corrections could be 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). Sentinel data downloaded from the Sentinel’s Data Hub were already processed. Data not published.

On the basis of glaciological and meteorological data collected on Werenskioldbreen, daily surface ablation for the period May - November for years 2009-2020 was calculated (PPD, temperature ablation model). 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.

The dataset includes point winter and summer mass balance measurements on ablation stakes in 2009-2020 and the calculated point annual mass balance. 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.

Average terminus height above sea level for the period 1992–1996, 2000 and 2010 was acquired with an accuracy of ±1.5 m, using terrestrial photogrammetry. The glacier terminus height in September 2009 and 2015 was measured using precise laser scanning with an accuracy of ±0.5 m. The height data obtained using photogrammetry and a laser scanner are averaged along the ice face. The database is the supplement to the paper: Małgorzata Błaszczyk, Jacek A. Jania, Michał Ciepły, Mariusz Grabiec, Dariusz Ignatiuk, Leszek Kolondra, Aleksandra Kruss, Bartłomiej Luks, Mateusz Moskalik, Tadeusz Pastusiak, Agnieszka Strzelewicz, Waldemar Walczowski, Tomasz Wawrzyniak. “Factors controlling terminus position of Hansbreen, a tidewater glacier in Svalbard”, Journal of Geophysical Research - Earth Surface, https://doi.org/10.1029/2020JF005763.

Precipitation measurements were made at AWS at Polish olar Station Hornsund (N77°00' E15°33') with a multi-type gauge that measured both solid and liquid. Results were into liquid water equivalent in millimeters. Precipitation measurements are slightly offset temporally, with a day defined as beginning at 6 a.m. on the observed day and ending 6 a.m. on the day after.

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.

Firn extents of Hansbreen and Werenskoildbreen delivered from unsupervised classifications of single, dual and fully-polarimetric SAR data (ALOS-2 PALSAR, RADARSAT-2, Sentinel-1, ERS-2 SAR) between 2011 and 2017. Methods of classification: unsupervised ISO classification, H-a Wishart Classification. Results validated with terrestrial measurements (shallow ice cores drilling, Ground Penetrating Radar measurements). Research supported by the European Space Agency, Third Party Missions grant and Svalbard Science Forum, Arctic Field Grant 2018. For more details, please e-mail to this adress: bbarzycka@us.edu.pl.

The ortophotomap of Hornsund Fiord with changes to the front positions of tidewater glaciers. The front positions are based on different cartographical maps and satellite data. The base map is Sentinel 2 satellite image acquired on 6 July 2018. Citation: Kolondra L., 2018. Hornsund Fiord - Changes to the front positions of tidewater glaciers. University of Silesia, Faculty of Earth Sciences.

Air temperature 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 instruments are serviced at least once a year between March and April.

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.