scholarly journals Supplementary material to "Modelling the future evolution of glaciers in the European Alps under the EURO-CORDEX RCM ensemble"

Author(s):  
Harry Zekollari ◽  
Matthias Huss ◽  
Daniel Farinotti
2016 ◽  
Vol 10 (6) ◽  
pp. 2693-2719 ◽  
Author(s):  
Antoine Marmy ◽  
Jan Rajczak ◽  
Reynald Delaloye ◽  
Christin Hilbich ◽  
Martin Hoelzle ◽  
...  

Abstract. Permafrost is a widespread phenomenon in mountainous regions of the world such as the European Alps. Many important topics such as the future evolution of permafrost related to climate change and the detection of permafrost related to potential natural hazards sites are of major concern to our society. Numerical permafrost models are the only tools which allow for the projection of the future evolution of permafrost. Due to the complexity of the processes involved and the heterogeneity of Alpine terrain, models must be carefully calibrated, and results should be compared with observations at the site (borehole) scale. However, for large-scale applications, a site-specific model calibration for a multitude of grid points would be very time-consuming. To tackle this issue, this study presents a semi-automated calibration method using the Generalized Likelihood Uncertainty Estimation (GLUE) as implemented in a 1-D soil model (CoupModel) and applies it to six permafrost sites in the Swiss Alps. We show that this semi-automated calibration method is able to accurately reproduce the main thermal condition characteristics with some limitations at sites with unique conditions such as 3-D air or water circulation, which have to be calibrated manually. The calibration obtained was used for global and regional climate model (GCM/RCM)-based long-term climate projections under the A1B climate scenario (EU-ENSEMBLES project) specifically downscaled at each borehole site. The projection shows general permafrost degradation with thawing at 10 m, even partially reaching 20 m depth by the end of the century, but with different timing among the sites and with partly considerable uncertainties due to the spread of the applied climatic forcing.


2018 ◽  
Author(s):  
Harry Zekollari ◽  
Matthias Huss ◽  
Daniel Farinotti

Abstract. Glaciers in the European Alps play an important role in the hydrological cycle, act as a source for hydroelectricity and have a large touristic importance. The future evolution of these glaciers is driven by surface mass balance and ice flow processes, which the latter is to date not included in regional glacier projections for the Alps. Here, we model the future evolution of glaciers in the European Alps with GloGEMflow, an extended version of the Global Glacier Evolution Model (GloGEM), in which both surface mass balance and ice flow are explicitly accounted for. The mass balance model is calibrated with glacier-specific geodetic mass balances, and forced with high-resolution regional climate model (RCM) simulations from the EURO-CORDEX ensemble. The evolution of the total glacier volume in the coming decades is relatively similar under the various representative concentrations pathways (RCP2.6, 4.5 and 8.5), with volume losses of about 47–52 % in 2050 with respect to 2017. We find that under RCP2.6, the ice loss in the second part of the 21st century is relatively limited and that about one-third (36.8 % ± 11.1 %) of the present-day (2017) ice volume will still present in 2100. Under a strong warming (RCP8.5) the future evolution of the glaciers is dictated by a substantial increase in surface melt, and glaciers are projected to largely disappear by 2100 (94.4 ± 4.4 % volume loss vs. 2017). For a given RCP, differences in future changes are mainly determined by the driving global climate model, rather than by the RCM that is coupled to it, and these differences are larger than those arising from various model parameters. We find that under a limited warming, the inclusion of ice dynamics reduces the projected mass loss and that this effect increases with the glacier elevation range, implying that the inclusion of ice dynamics is likely to be important for global glacier evolution projections.


2021 ◽  
Author(s):  
Loris Compagno ◽  
Sarah Eggs ◽  
Matthias Huss ◽  
Harry Zekollari ◽  
Daniel Farinotti

Abstract. With the Paris Agreement, the urgency of limiting ongoing anthropogenic climate change has been recognized. More recent discussions have focused on the difference of limiting the increase in global average temperatures below 1.0, 1.5, or 2.0 °C compared to pre-industrial levels. Here, we assess the impacts that such different scenarios would have on both the future evolution of glaciers in the European Alps and the water resources they provide. Our results show that the different temperature targets 5 have important implications for the changes predicted until 2100, and that glaciers might start recovering after the end of the 21st century.


2015 ◽  
Vol 9 (5) ◽  
pp. 4787-4843 ◽  
Author(s):  
A. Marmy ◽  
J. Rajczak ◽  
R. Delaloye ◽  
C. Hilbich ◽  
M. Hoelzle ◽  
...  

Abstract. Permafrost is a widespread phenomenon in the European Alps. Many important topics such as the future evolution of permafrost related to climate change and the detection of permafrost related to potential natural hazards sites are of major concern to our society. Numerical permafrost models are the only tools which facilitate the projection of the future evolution of permafrost. Due to the complexity of the processes involved and the heterogeneity of Alpine terrain, models must be carefully calibrated and results should be compared with observations at the site (borehole) scale. However, a large number of local point data are necessary to obtain a broad overview of the thermal evolution of mountain permafrost over a larger area, such as the Swiss Alps, and the site-specific model calibration of each point would be time-consuming. To face this issue, this paper presents a semi-automated calibration method using the Generalized Likelihood Uncertainty Estimation (GLUE) as implemented in a 1-D soil model (CoupModel) and applies it to six permafrost sites in the Swiss Alps prior to long-term permafrost evolution simulations. We show that this automated calibration method is able to accurately reproduce the main thermal condition characteristics with some limitations at sites with unique conditions such as 3-D air or water circulation, which have to be calibrated manually. The calibration obtained was used for RCM-based long-term simulations under the A1B climate scenario specifically downscaled at each borehole site. The projection shows general permafrost degradation with thawing at 10 m, even partially reaching 20 m depths until the end of the century, but with different timing among the sites. The degradation is more rapid at bedrock sites whereas ice-rich sites with a blocky surface cover showed a reduced sensitivity to climate change. The snow cover duration is expected to be reduced drastically (between −20 to −37 %) impacting the ground thermal regime. However, the uncertainty range of permafrost projections is large, resulting mainly from the broad range of input climate data from the different GCM-RCM chains of the ENSEMBLES data set.


2019 ◽  
Vol 13 (4) ◽  
pp. 1125-1146 ◽  
Author(s):  
Harry Zekollari ◽  
Matthias Huss ◽  
Daniel Farinotti

Abstract. Glaciers in the European Alps play an important role in the hydrological cycle, act as a source for hydroelectricity and have a large touristic importance. The future evolution of these glaciers is driven by surface mass balance and ice flow processes, of which the latter is to date not included explicitly in regional glacier projections for the Alps. Here, we model the future evolution of glaciers in the European Alps with GloGEMflow, an extended version of the Global Glacier Evolution Model (GloGEM), in which both surface mass balance and ice flow are explicitly accounted for. The mass balance model is calibrated with glacier-specific geodetic mass balances and forced with high-resolution regional climate model (RCM) simulations from the EURO-CORDEX ensemble. The evolution of the total glacier volume in the coming decades is relatively similar under the various representative concentrations pathways (RCP2.6, 4.5 and 8.5), with volume losses of about 47 %–52 % in 2050 with respect to 2017. We find that under RCP2.6, the ice loss in the second part of the 21st century is relatively limited and that about one-third (36.8 % ± 11.1 %, multi-model mean ±1σ) of the present-day (2017) ice volume will still be present in 2100. Under a strong warming (RCP8.5) the future evolution of the glaciers is dictated by a substantial increase in surface melt, and glaciers are projected to largely disappear by 2100 (94.4±4.4 % volume loss vs. 2017). For a given RCP, differences in future changes are mainly determined by the driving global climate model (GCM), rather than by the RCM, and these differences are larger than those arising from various model parameters (e.g. flow parameters and cross-section parameterisation). We find that under a limited warming, the inclusion of ice dynamics reduces the projected mass loss and that this effect increases with the glacier elevation range, implying that the inclusion of ice dynamics is likely to be important for global glacier evolution projections.


2021 ◽  
Author(s):  
Loris Compagno ◽  
Sarah Eggs ◽  
Matthias Huss ◽  
Harry Zekollari ◽  
Daniel Farinotti

<p>With the Paris Agreement, leaders of the world have recognized the urgency of limiting ongoing, anthropogenic climate change. In preparation of the upcoming 26<sup>th</sup> UN Climate Change Conference of the Parties, discussions have been focusing on the difference of limiting the increase in global average temperatures below 1.0, 1.5, or 2.0°C compared to pre-industrial levels. Here, we assess the impacts that such different scenarios would have on both the future evolution of glaciers in the European Alps and the water resources they provide. We force the combined glacier mass balance and ice flow model GloGEMflow with climate projections from Coupled Model Intercomparison Project Phase 6 (CMIP6), and compute the area and volume evolution of all 3926 glaciers of the European Alps for the period 1990 to 2100. Our results show that the different temperature targets have important implications for the predicted changes: in a +1.0°C scenario, glaciers in the European Alpsare<span>  </span>projected to lose 44 ± 21 % of their 2020 ice volume; 68 ± 12 % in a +1.5 °C scenario; while 81 ± 8% in a +2.0°C scenario. The changes in glacier volume will strongly impact the water yield from presently-glacierized catchments, with 2080-2100 yearly average runoffs decreasing by 25 ± 6% (for a global warming of +1.0°C), 32 ± 8%, (+1.5°C) and 36 ± 10% (+2.0°C) when compared to 2000-2020 levels. Changes in peak runoff -- anticipated to occur 1 to 2 months earlier by the end of the century than it does today -- will be even more pronounced, with reductions of 23 ± 15 %, 29 ± 14 %, and 37 ± 15 % in the three warming scenarios, respectively.</p>


2021 ◽  
Vol 15 (6) ◽  
pp. 2593-2599
Author(s):  
Loris Compagno ◽  
Sarah Eggs ◽  
Matthias Huss ◽  
Harry Zekollari ◽  
Daniel Farinotti

Abstract. With the Paris Agreement, the urgency of limiting ongoing anthropogenic climate change has been recognised. More recent discussions have focused on the difference of limiting the increase in global average temperatures below 1.0, 1.5, or 2.0 ∘C compared to preindustrial levels. Here, we assess the impacts that such different scenarios would have on both the future evolution of glaciers in the European Alps and the water resources they provide. Our results show that even half-degree differences in global temperature targets have important implications for the changes predicted until 2100, and that – for the most optimistic scenarios – glaciers might start to partially recover, owing to possibly decreasing temperatures after the end of the 21st century.


2019 ◽  
pp. 75-89
Author(s):  
A.B. Lyubinin

The article comments on the concept of «socialism with Chinese specificity», which forms the ideological basis of the «Chinese miracle». The ideological origins of this concept, starting with Confucianism, are revealed. It has evolved to become increasingly pragmatic and to adapt to the realities of national and global development. The relation of this concept with the Marxist concept of socialism is shown. The article substantiates the fundamental theoretical thesis that in the objective-essential sense (in the elimination of, in particular, national specifics) Chinese society is a transitional form to socialism (a certain analogue of the Soviet society of the NEP period). The author talks about a «heterogeneous», «mixed» socio-economic system, the vector and nature of the future evolution of which will depend crucially on the strategic course of the CPC.


2021 ◽  
Vol 503 (1) ◽  
pp. 594-602
Author(s):  
R Schiavi ◽  
R Capuzzo-Dolcetta ◽  
I Y Georgiev ◽  
M Arca-Sedda ◽  
A Mastrobuono-Battisti

ABSTRACT We use direct N-body simulations to explore some possible scenarios for the future evolution of two massive clusters observed towards the centre of NGC 4654, a spiral galaxy with mass similar to that of the Milky Way. Using archival HST data, we obtain the photometric masses of the two clusters, M = 3 × 105 M⊙ and M = 1.7 × 106 M⊙, their half-light radii, Reff ∼ 4 pc and Reff ∼ 6 pc, and their projected distances from the photometric centre of the galaxy (both <22 pc). The knowledge of the structure and separation of these two clusters (∼24 pc) provides a unique view for studying the dynamics of a galactic central zone hosting massive clusters. Varying some of the unknown cluster orbital parameters, we carry out several N-body simulations showing that the future evolution of these clusters will inevitably result in their merger. We find that, mainly depending on the shape of their relative orbit, they will merge into the galactic centre in less than 82 Myr. In addition to the tidal interaction, a proper consideration of the dynamical friction braking would shorten the merging times up to few Myr. We also investigate the possibility to form a massive nuclear star cluster (NSC) in the centre of the galaxy by this process. Our analysis suggests that for low-eccentricity orbits, and relatively long merger times, the final merged cluster is spherical in shape, with an effective radius of few parsecs and a mass within the effective radius of the order of $10^5\, \mathrm{M_{\odot }}$. Because the central density of such a cluster is higher than that of the host galaxy, it is likely that this merger remnant could be the likely embryo of a future NSC.


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