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Université de Fribourg

Possible species-flock scenario for the evolution of the cyprinid genus Capoeta (Cypriniformes: Cyprinidae) within late Neogene lake systems of the Armenian Highland

Ayvazyan, Anna ; Vasilyan, Davit ; Böhme, Madelaine

In: PLOS ONE, 2019, vol. 14, no. 5, p. e0215543

We studied 4 Ma old isolated pharyngeal teeth from lake sediments of Çevirme (Tekman Palaeolake, Erzurum Province). Based on shape characters defined for 3D models of modern species, we found that the Pliocene lake constitutes sympatric occurrence of four Capoeta species (C. cf. umbla, C. cf. baliki, C. cf. sieboldi and C. sp. sevangi/capoeta), whose modern relatives belong to a monophyletic...

Université de Fribourg

Strong contrast in mass and energy balance between a coastal mountain glacier and the Greenland ice sheet

Abermann, Jakob ; As, Dirk Van ; Wacker, Stefan ; Langley, Kirsty ; Machguth, Horst ; Fausto, Robert Schjøtt

In: Journal of Glaciology, 2019, vol. 65, no. 250, p. 263–269

We show a strong difference in surface mass and energy balance of a mountain glacier and two sites on the ice sheet at 64°N in West Greenland using stake and automated weather station observations. Net surface mass balance is on average 2.2 m w.e. less negative at the coast compared with the ice sheet in the same elevation. We find a larger energy turnover at the ice sheet margin on...

Université de Fribourg

GlacierMIP – A model intercomparison of global-scale glacier mass-balance models and projections

Hock, Regine ; Bliss, Andrew ; Marzeion, Ben ; Giesen, Rianne H. ; Hirabayashi, Yukiko ; Huss, Matthias ; Radić, Valentina ; Slangen, Aimée B. A.

In: Journal of Glaciology, 2019, vol. 65, no. 251, p. 453–467

Global-scale 21st-century glacier mass change projections from six published global glacier models are systematically compared as part of the Glacier Model Intercomparison Project. In total 214 projections of annual glacier mass and area forced by 25 General Circulation Models (GCMs) and four Representative Concentration Pathways (RCP) emission scenarios and aggregated into 19 glacier ...

Université de Fribourg

Disappearing world heritage glaciers as a keystone of nature conservation in a changing climate

Bosson, J.‐B. ; Huss, Matthias ; Osipova, E.

In: Earth’s Future, 2019, vol. 7, no. 4, p. 469–479

Since 1972, the United Nations Educational, Scientific and Cultural Organization (UNESCO) World Heritage Convention aims to identify and protect sites of Outstanding Universal Value for future generations. However, growing impacts of climate change are of the utmost concern for the integrity of many sites. Here, we inventory the glaciers present in natural World Heritage sites for the first...

Université de Fribourg

Calibrated ice thickness estimate for all glaciers in Austria

Helfricht, Kay ; Huss, Matthias ; Fischer, Andrea ; Otto, Jan-Christoph

In: Frontiers in Earth Science, 2019, vol. 7, p. -

Knowledge on ice thickness distribution and total ice volume is a prerequisite for computing future glacier change for both glaciological and hydrological applications. Various ice thickness estimation methods have been developed but regional differences in fundamental model parameters are substantial. Parameters calibrated with measured data at specific points in time and space can vary when...

Université de Fribourg

A non-archaeopterygid avialan theropod from the Late Jurassic of southern Germany

Rauhut, Oliver W. M. ; Tischlinger, Helmut ; Foth, Christian

In: eLife, 2019, vol. 8, p. e43789

The Late Jurassic ‘Solnhofen Limestones’ are famous for their exceptionally preserved fossils, including the urvogel Archaeopteryx, which has played a pivotal role in the discussion of bird origins. Here we describe a new, non-archaeopterygid avialan from the Lower Tithonian Mörnsheim Formation of the Solnhofen Archipelago, Alcmonavis poeschli gen. et sp. nov. Represented by a right...

Université de Fribourg

Northern Hemisphere permafrost map based on TTOP modelling for 2000–2016 at 1 km2 scale

Obu, Jaroslav ; Westermann, Sebastian ; Bartsch, Annett ; Berdnikov, Nikolai ; Christiansen, Hanne H. ; Dashtseren, Avirmed ; Delaloye, Reynald ; Elberling, Bo ; Etzelmüller, Bernd ; Kholodov, Alexander ; Khomutov, Artem ; Kääb, Andreas ; Leibman, Marina O. ; Lewkowicz, Antoni G. ; Panda, Santosh K. ; Romanovskyh, Vladimir ; Wayk, Robert G. ; Westergaard-Nielsen, Andreas ; Wu, Tonghua ; Yamkhin, Jambaljav ; Zou, Defu

In: Earth-Science Reviews, 2019, vol. 193, p. 299–316

Permafrost is a key element of the cryosphere and an essential climate variable in the Global Climate Observing System. There is no remote-sensing method available to reliably monitor the permafrost thermal state. To estimate permafrost distribution at a hemispheric scale, we employ an equilibrium state model for the temperature at the top of the permafrost (TTOP model) for the 2000–2016...

Université de Fribourg

On trends and patterns in macroevolution: Williston’s law and the branchiostegal series of extant and extinct osteichthyans

Ascarrunz, Eduardo ; Sánchez-Villagra, Marcelo R. ; Betancur, Ricardo ; Laurin, Michel

In: BMC Evolutionary Biology, 2019, vol. 19, no. 1, p. 117

The branchiostegal series consists of an alignment of bony elements in the posterior portion of the skull of osteichthyan vertebrates. We trace the evolution of the number of elements in a comprehensive survey that includes 440 extant and 66 extinct species. Using a newly updated actinopterygian tree in combination with phylogenetic comparative analyses, we test whether osteichthyan...