Hornsund area extracted from different archive data. Detailed description of the source data and accuracy data for glaciers from hydrological basin of Hornsund can be found in: Błaszczyk M., Jania J.A., Kolondra L., 2013: Fluctuations of tidewater glaciers in Hornsund Fiord (Southern Svalbard) since the beginning of the 20th century. Polish Polar Research, 34( 4): 327-352. http://journals.pan.pl/dlibra/publication/114504/edition/99557/content

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

Relative humidity 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.

Ice condition directly at the Hansbreen front is obtained from visual interpretation of oblique pictures taken at 3 h intervals by Canon EOS 1000D time-lapse photography (Figure 1) for the period 2010–2015 (https://ppdb.us.edu.pl/geonetwork/srv/pol/catalog.search;jsessionid=muhaqbum8pz21xknjo0crhodn?node=srv#/metadata/cf6a17fd-ec3a-4ff6-8232-67a0dc5957d4) 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.

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.

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.

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.

Ice front position of the tidewater glaciers in Hornsund was examined during the following periods: 1899–1936–1960/1961–1976–1990–2001–2005–2010. For the period 1899–1990, several archival maps of varying accuracy were used, sometimes difficult to assess. For the period 1976–2010 multispectral and radar satellite images were used. Detailed description of the source data and accuracy can be found in: Błaszczyk M., Jania J.A., Kolondra L., 2013: Fluctuations of tidewater glaciers in Hornsund Fiord (Southern Svalbard) since the beginning of the 20th century. Polish Polar Research, 34(4): 327-352.

The base contain: 1. List (*xls) of terrophotogrammetric photographs taken by member of Polish Expedition on Iceland in 1968 (zone of Skeidarárjökull). 2. Skaning above photographs with resolution of 2400 dpi, file format *.tif and *.jpg (400 dpi). All photographs were taken by means of instrument type Phototheodolite Zeiss 19/1318 on glass plates. Authors of photographs: Tadeusz Konysz. Fot better identification of all photographs was prepared presentations (in *.pptx and *.pdf formats), where photographs there are arranged in in common practise, classic form used for terrophotogrammetric stereoscopic photographs: A, AL, AR, B, BL, BR (the meaning of a letter: A - right photogrammetric station and photograph taken in normal case [90°]; B - left photogrammetric station and photograph taken in normal case [90°]; AL - photograph taken from right station in left direction; AR - photograph taken from right station in right direction; BL - photograph taken from left station in left direction; BR - photograph taken from left station in right direction). Other photographs (e.g. panoramic) has additional informations. All names of photogrammetric stations and name of objects (in Polish language) was taken from the author’s collection of data.

Glaciers facies extents of Langjökull delivered from unsupervised classifications of fully-polarimetric SAR data (ALOS-2 PALSAR, RADARSAT-2) for 2018 year. Date of SAR images acquisitions: 12, 16 Mar 2018 (Fine Quad Pol RADARSAT-2), 17 Mar 2018 (High Sensitive Quad Pol ALOS-2 PALSAR). Method of classification: H-a Wishart Classification. Results validated with terrestrial measurements (shallow ice cores drilling, Ground Penetrating Radar measurements). Research done with cooperation with University of Iceland and supported by the European Space Agency, Third Party Miassions. Overwiew of results of RADATSAT-2 (16 Mar 2018; Fine Quad Pol) classification of south part of Langjökull. Black line - contour of Langjökull; other colours - different scattering properties of SAR microwaves. For more details please contact Barbara Barzycka (bbarzycka@us.edu.pl).