10 years of in-situ glacier monitoring on Freya Glacier (NE Greenland) History. Main Results. Accumulation anomaly 2017/18 Bernhard Hynek1, Daniel Binder1,2, Jakob Abermann3 Gernot Weyss1, Gernot Resch3, Marc Olefs1 Michele Citterio2, Wolfgang Schöner3 et al. 1 Zentralanstalt für Meteorologie und Geodynamik (ZAMG), Wien 2 Geological Survey of Denmark and Greenland (GEUS), Copenhagen 3 Universität Graz, Institut für Geographie und Raumforschung, Graz presented at the General Assembly of the Austrian Polar Research Institute, Wien, Nov. 2018 Start of glacier monitoring by ZAMG in IPY 2007/2008 Zackenberg Research Station Wollaston Foreland A.P. Olsen Icecap Freya Glacier GrIS Payer Land Clavering Island Young Sound Skille Glacier (Vintergata Gl.) Daneborg Station Fig. 1: Map of Mass Balance and Fig. 2: Satellite Image of the Greenlandic East Fig. 3: Satellite Image of the Zackenberg Area with north Energy Balance Measurements in Cost in the Zackenberg Area with Clavering Island part of Clavering Island. Freya Glacier is about 15 km far Greenland until 1995 (Weidick, (Source: Google Earth). from the Zackenberg Station. In summer, Tyroler Fjord can 1995Zackenberg) Research Station, 74°N since 1995 open May - Octbe crossed by Zodiac. (Source: Google Earth). Foto: B.Hynek Start of glacier monitoring by ZAMG in IPY 2007/2008 Zackenberg Research Station Wollaston Foreland A.P. Olsen Icecap Freya Glacier GrIS Payer Land Clavering Island Young Sound Skille Glacier (Vintergata Gl.) Daneborg Station Fig. 1: Map of Mass Balance and Fig. 2: Satellite Image of the Greenlandic East Fig. 3: Satellite Image of the Zackenberg Area with north Energy Balance Measurements in Cost in the Zackenberg Area with Clavering Island part of Clavering Island. Freya Glacier is about 15 km far Greenland until 1995 (Weidick, (Source: Google Earth). from the Zackenberg Station. In summer, Tyroler Fjord can 1995) be crossed by Zodiac. (Source: Google Earth). On Freya Glacier, mass and energy balance measurements have been carried out by Ahlmann et al in the 1930s. Two adjacent mass balance monitoring programs Fotos: B.Hynek A.P. Olsen SE outlet glacier Freya Glacier Monitoring by GEUS Monitoring by ZAMG Since 2007 Since 2007 Two adjacent mass balance monitoring programs Fotos: B.Hynek A.P. Olsen SE outlet glacier Freya Glacier Monitoring by GEUS Monitoring by ZAMG Since 2007 Since 2007 Zackenberg River Catchment IPY – studies by Ahlmann in late 1930s ~100 km² 5.3km² 550-1450 m a.s.l. SE 270-1300 m a.s.l. NW ~15 stakes ~15 stakes 3 AWS 1 AWS GLOF: camera, passive seismic, GPS 2 Cameras for snowline monitoring Fieldwork in May Fieldwork in August and May AWS Freya Glacier: first field work in 2007, first mass balance 2007/2008 All Fotos: B.Hynek Mass balance of Freya Glacier compared with Alpine Glaciers monitored by ZAMG meter water equivalent First spring fieldwork 2008 – Radar Survey Fotos: B.Hynek, G.Weyss, J.Abermann, M. Olefs Measurements of ice thickness distribution and thermal state The thickest ice found during a GPR survey in May 2008 is 200m, located at the confluence of the two accumulation areas. GPR-data suggest, that Freya Glacier is a polythermal glacier with temperate ice in a limited area only, at the ELA near the bottom of the glacier. Strain heating May 2008 GPR 40MHz Difficult years: three years without visit in spring: to warm, no funding… Spring 2009: it was not possible to cross the fjord to reach the glacier from Zackenberg Research Station because of ongoing surface melt. Foto: G. Weyss Time Series of winter and annual surface mass balance of Freya Glacier. There is a strong correlation between winter accumulation and annual mass balance. No data… 2011: The first Automatic Weather Station. EU-Interact Grants and ÖGPF student grants Spatial variability of surface mass balance - refreezing 12.8.2013 -1.5 m -0.8 m 2013 DEM of surface topography with a novel method -- second AWS ~900 terrestrial Fotos ~ 100 GCP‘s, visible on Images DEM 2013: structure from motion multiview stereo photogrammetry (terrestrial photos) Image Acquisition: Nikon D7100, 24Mpix, 20mm distance : 1km viewing angle: 25° DEM resolution: 1m Processed with PhotoScan Based on Area and DEM 2013 Reanalysis of mass balance mean RE rmse of GCPs [m] Part Cams [pixel] X Y Z TOT Lower 163 0.43 0.14 0.13 0.12 0.22 Upper 262 0.37 0.21 0.14 0.13 0.29 2016: Glacio-Live: Freya Glacier goes online – CAMS, GEUS-AWS and a new monitoring strategy Within the project Glacio-Live two automatic stations have been put up on the glacier in May 2016. An automatic weather station that measures the surface energy balance and the surface height change and two automatic cameras that monitor the snowline retreat during summer. Both stations transmit the data in near real time via Iridium Satellite network. Installation Kameras Freya Glacier 28.11.2018 Folie 16 Installation Kameras Freya Glacier 2016 Freya Glacier goes online – CAMS, GEUS-AWS and a new monitoring strategy Example Kleinfleißkees: Results from Rojs (2016). Daily orthofoto production and surface classification (ice/firn/snow) using the photo rectification and classification software Practise (Härer et al., 2016). The two cameras are monitoring the snow cover on the glacier during the summer season. From one location almost the whole glacier surface is visible. Current station network: 10 Cameras 28.11.2018 Folie 19 foto-webcam.eu Links: foto-webcam.eu/webcams/freya1 foto-webcam.eu/webcams/freya2 glacio-live.at Time Lapse Movie: https://www.youtube.com/watch?v=2SSiARL0XBg Installation CAMS Freya Gletscher 2016 28.11.2018 Folie 20 Accumulation anomaly over East Greenland in winter 2017/2018 Source: polarportal.org Foto: D. Binder, 2018 The AWS (4m tall) was burried in winter accumulation in May 2018 Fotos: D. Binder, 2018 Large avalanche deposits were visible on the surface of Freya Glacier. Fotos: D. Binder, 2018 Ground-penetrating radar (GPR) Survey 2018 Snow depth up to 10 m in avalanche deposits! Snow depth distribution and mass balance in 2017 and 2018 Time Series of mean winter snow depth Snowdepth distribution derived from Radar Survey (blue, in meter) and annual mass balance (grey in meter) of Freya Glacier Snow depth distribution and surface slope To what degree the surface mass balance of Freya Glacier influenced by avalanche deposits? Surface Slope DEM 2013 Conclusions: • Freya Glacier is a polythermal glacier with an maximum ice thickness of around 240 meters (2008). • The mean annual surface mass balance (2007-2017) was -0.45 m w.e./y. • This corresponds to a mean ice thickness loss of -5.5 m in the last 11 years. • Mean winter accumulation is 800 mm w.e. (8years mean value) • Variability of annual mass balance is dominated by winter precipitation anomaly. • Accumulation 2017/18 was twice as high as on average due to several heavy snow fall events. • Massive avalanche deposits were visible for the first time since 10 years of monitoring activities. Open Questions: • How large is the influence of refreezing on the surface mass balance? • Was the winter 2017/18 outstanding or did it happen more frequently in the past? • Can we expect heavy accumulation winters more often due to global warming? • Is or was the surface mass balance of Freya glacier significantly influenced by avalanches? • Are avalanche deposits responsible for the characteristic surface undulations of Freya Glacier? Thanks for your attention! References: Hynek, B. Weyss, G.; Binder, D.; Schöner, W.; Abermann, J.; Citterio, M. (2014): Mass balance of Freya Glacier, Greenland since 2007/2008. Zentralanstalt für Meteorologie und Geodynamik, Wien. PANGAEA, https://doi.org/10.1594/PANGAEA.831035 Hynek, B.; Binder, D.; Abermann, J.; Citterio, M. (2017): Mass Balance Freya Glacier 2014-15. Technical Report, Zentralanstalt für Meteorologie und Geodynamik, Wien, 21 pp, pdf Hynek B., G. Verhoeven, D. Binder, G. Boffi, and W. Schöner, 2014: Application of terrestrial ’structure-from-motion’ photogrammetry on a medium-size arctic valley glacier: potential, accuracy and limitations. Geophysical Research Abstracts Vol.16, EGU2014-1783, 2014 Hynek B., G. Weyss, D. Binder, and W. Schöner, 2013: Mass balance monitoring on Freya glacier. In Jensen, L.M., Rasch, M. and Schmidt N.M. (ed.), 2013. Zackenberg Ecological Research Operations, 18th Annual Report, 2012. Aarhus University, DCE - Danish Centre for Environment and Energy, 122 pp., 2013. Hynek B., Binder D., News Report on the Winter Accumulation Anomaly over East Greenland. 23.3.2018. zamg.ac.at. https://www.zamg.ac.at/cms/de/klima/news/ungewoehnlich-viel-schnee-in-groenland-zehn-jahre-arktisches-gletschermonitoring-der-zamg Machguth, H., Thomsen, H.H., Weidick, A., Ahlstøhm, A.P., Abermann, J., Andersen, M.L., Andersen, S.B., Bjørk, A.A., Box, J.E., Braithwaite, R.J., Bøggild, C.E., Citterio, M., Clement, P., Colgan, W., Fausto, R.S., Gleie, K., Gubler, S., Hasholt, B., Hynek, B., Knudsen, N.T., Larsen, S.H., Mernild, S.H., Oerlemans, J., Oerter, H., Olesen, O.B., Smeets, C.J.P.P., Steffen, K., Stober, M., Sugiyama, S., Van As, D., Van Den Broeke, M.R. and Van De Wal, R.S.W. 2016: Greenland surface mass-balance observations from the ice-sheet ablation area and local glaciers, Journal of Glaciology, 62(235), pp. 861–887. doi: 10.1017/jog.2016.75. Resch G., B. Hynek, G. Weyss, G. Heinrich and W. Schöner, 2018: Refreezing of melt water in the snow pack of Freya Glacier in North-East- Greenland. Geophysical Research Abstracts Vol.20, EGU2018-7738-2, 2018 Acknowledgements: This research was funded by the Austrian Federal Ministry of Science, Research and Economy (research projects Glacio-Live and FERMAP-Pilot), the European Union (EU-Interact) and the Austrian Polar Research Institute. .