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.

The monitoring of the mass balance of the Werenskioldbreen (Wedel Jarlsberg Land, Spitsbergen, Svalbard) in the years 1999-2002 and 2009-2018. It is calculated on the base of 4 to 9 ablation stakes (depend on year). The mass balance is determined by conducting field surveys on floating calendar dates (floating-date system). Data have also been submitted to the World Glacier Monitoring Sevice (WGMS, https://wgms.ch)

• 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

The base contain: 1. List (*xls) of terrophotogrammetric photographs taken by Poles na Spitsbergen from 1934 till 2016: 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: Antoni Rogala-Zawadzki, Cezary Lipert, Stanisław Rudowski, Leszek Kolondra, Jacek Jania, Jerzy Wach, Krzysztof Migała, Janusz Karkoszka, Małgorzata Błaszczyk and other unknown members of Polish Expeditions organized by Institute of Geophysic Polish Academy of Science in Station HORNSUND. Fot better identification of all photographs was prepared presentations (in *.pptx and *.pdf formats), where photographs there are arranged in 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. Boths kind of presentation are prepared in chronological and tematical (for objects) order.

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

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.

Dataset contains surface elevation along spring GPR profiles performed on Hansbreen and Werenskioldbreen. Fieldwork has been done with dGPS device in kinematic mode at the end of ablation season in 2013 and 2015 to compare it with spring GPR survey and calculate surface ablation. 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)

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).

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.