Reconstructing LGM paleoglaciers and their ELAs along the southern fringe of the Eastern European Alps

2021 ◽  
Author(s):  
Lukas Rettig ◽  
Francesco Ferrarese ◽  
Giovanni Monegato ◽  
Paolo Mozzi ◽  
Matteo Spagnolo
Keyword(s):  
Large Scale ◽  
Equilibrium Line ◽  
European Alps ◽  
The South ◽  
Equilibrium Line Altitude ◽  
Radiocarbon Dates ◽  
Mountainous Regions ◽  
South Eastern ◽  
Wide Range ◽  
Southern Fringe

<p>The reconstruction of paleoglaciers and specifically the calculation of their equilibrium line altitude (ELA) is an important source of quantitative paleoclimatic information in mountainous regions. During the Last Glacial Maximum (LGM), the prealpine massifs in the south-eastern part of the Alpine chain (Venetian Prealps, Carnic Prealps and Julian Prealps) hosted several small valley glaciers and local ice caps that were isolated from the larger ice-streams occupying the major valleys. Because of their small size and independent dynamics these glaciers can be considered as excellent indicators of local climatic conditions. Although this potential has long been recognised and the sediments and landforms related to these glaciations have been mapped in a few areas, a regional perspective on this type of glaciation is still lacking. This is primarily due to the wide range of methods of ELA reconstructions that has been applied historically, which makes a solid comparison between different localities difficult.</p><p>Here, we present a detailed re-evaluation of local LGM glaciation in the south-eastern Alps based on a large-scale survey of remote sensing data and targeted field work at selected localities. Recently developed GIS tools were applied for the reconstruction of paleoglacier geometries and ELAs (Pellitero et al. 2015, 2016). The obtained values are used both to discuss regional climatic patterns during the LGM and site-specific topographic factors. A specific focus is set on the Monte Cavallo group, where glacial sediments from the LGM are covering a thick sequence of interstadial lacustrine deposits. A set of new radiocarbon dates from this succession provides a first chronological control on the onset of glacier expansion in this part of the Alpine chain.</p><p> </p><p>References:</p><p>Pellitero, R. et al. 2015. A GIS tool for automatic calculation of glacier equilibrium-line altitudes. Computers & Geosciences 82: 55-62.</p><p>Pellitero, R. et al. 2016. GlaRe, a GIS tool to reconstruct the 3D surface of palaeoglaciers. Computers & Geosciences 94: 77-85.</p>

scholarly journals Semi-automated calibration method for modelling of mountain permafrost evolution in Switzerland

2016 ◽  
Vol 10 (6) ◽  
pp. 2693-2719 ◽  
Author(s):  
Antoine Marmy ◽  
Jan Rajczak ◽  
Reynald Delaloye ◽  
Christin Hilbich ◽  
Martin Hoelzle ◽  
...  
Keyword(s):  
Large Scale ◽  
Calibration Method ◽  
Swiss Alps ◽  
Climate Projections ◽  
European Alps ◽  
Permafrost Degradation ◽  
Future Evolution ◽  
Mountainous Regions ◽  
Automated Calibration ◽  
The Future

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.

scholarly journals Glacier equilibrium line altitude variations during the “Little Ice Age” in the Mediterranean Andes (30◦–37◦ S)

2019 ◽  
Author(s):  
Álvaro González-Reyes ◽  
Claudio Bravo ◽  
Mathias Vuille ◽  
Martin Jacques-Coper ◽  
Maisa Rojas ◽  
...  
Keyword(s):  
Little Ice Age ◽  
Pearson Correlation ◽  
Temporal Changes ◽  
Global Climate Models ◽  
Ice Age ◽  
Equilibrium Line ◽  
Equilibrium Line Altitude ◽  
Mountainous Regions ◽  
The Mean ◽  
The Mediterranean

Abstract. The "Little Ice Age" (LIA; 1500–1850 Common Era (CE)), has long been recognized as the last period when mountain glaciers in many regions of the Northern Hemisphere (NH) recorded extensive growth intervals in terms of their ice mass and frontal position. The knowledge about this relevant paleoclimatic interval is vast in mountainous regions such as the Alps and Rocky Mountains in North America. However, in extra-tropical Andean sub-regions such as the Mediterranean Andes of Chile and Argentina (MA; 30º–37º S), the LIA has been poorly documented. Paradoxically, the few climate reconstructions performed in the MA based on lake sediments and tree rings do not show clear evidence of a LIA climate anomaly as observed in the NH. In addition, recent studies have demonstrated temporal differences between mean air temperature variations across the last millennium between both hemispheres. This motivates our hypothesis that the LIA period was not associated with a significant climate perturbation in the MA region. Considering this background, we performed an experiment using daily climatic variables from three Global Climate Models (GCMs) to force a novel glaciological model. In this way, we simulated temporal variations of the glacier equilibrium-line altitude (ELA) to evaluate the glacier response during the period 1500–1848 CE. Overall, each GCM shows temporal changes in annual ELA, with anomalously low elevations during 1640–1670 and 1800–1848 CE. An interval with high ELA values was identified during 1550–1575 CE. The spectral properties of the mean annual ELA in each GCM present significant periodicities between 2–7 years, and also significant decadal to multi-decadal signals. In addition, significant and coherent cycles at interannual to multi-decadal scales were detected between modeled mean annual ELAs and the first EOF1 extracted from Sea Surface Temperature (SST) within the El Niño 3.4 of each GCM. Finally, significant Pearson correlation coefficients were obtained between the mean annual ELA and Pacific SST on interannual to multi-decadal timescales. According to our findings, we propose that Pacific SST variability was the main modulator of temporal changes of the ELA in the MA region of South America during 1500–1848 CE.

scholarly journals Characteristics of shallow thermally driven flow in the complex topography of the south-eastern Adriatic

2010 ◽  
Vol 28 (10) ◽  
pp. 1905-1922 ◽  
Author(s):  
M. T. Prtenjak ◽  
I. Tomažić ◽  
I. Kavčič ◽  
S. Đivanović
Keyword(s):  
Large Scale ◽  
Sea Breeze ◽  
Small Scale ◽  
The South ◽  
Fine Grid ◽  
Easterly Wind ◽  
Sodar Data ◽  
South Eastern ◽  
The North ◽  
Convergence Zones

Abstract. Characteristics of thermally induced flow, namely the sea breeze, are investigated along the south-eastern Adriatic. The chosen period 24–25 April 2006 favoured sea breeze development and simultaneously allowed a comparison of the large-scale wind influence (north-westerly wind versus south-easterly wind) and the complex terrain on the local circulations. Particular attention is paid to the small-scale formation of the wind field, convergence zones (CZs), channelling flows and small scale eddies, especially in the vicinity of two airports in the central part of south-eastern Adriatic. The results are based on wind measurements (from meteorological surface stations, radiosoundings, satellite data and sodar data) and further supplemented by model data at fine grid spacing. This study shows the formation of numerous irregular daytime and nighttime CZs, which occurred along the coastline in the lee of mountains and over the larger, elongated islands. The results show that the above mentioned airports are surrounded by daytime CZ formations within the lowermost 1000 m and associated updrafts of 1 m s−1, especially if CZs are maintained by the north-westerly large-scale winds. Whereas the daytime CZ was generated due to merged sea breezes, the weaker and shallower nighttime CZs were formed by wind convergence of the seaward breezes, and significantly modified by the large-scale flow of the topography (e.g., accelerated flow in the sea channels and substantial swirled flows around the islands). The passes between the coastal mountain peaks changed the inflow penetration, provoking the increase in wind speed of the channelled flow. The strongest sea breeze channelling was observed above the valley of the Neretva River, where the onshore flow reached 40 km inland with a strength of 8 m s−1, and the highly asymmetric offshore part was confined within the sea channel.

scholarly journals Large-scale and synoptic meteorology in the South-East Pacific during the observations campaign VOCALS-REx in Spring 2008

2011 ◽  
Vol 11 (1) ◽  
pp. 225-288 ◽  
Author(s):  
T. Toniazzo ◽  
S. J. Abel ◽  
R. Wood ◽  
C. R. Mechoso ◽  
G. Allen ◽  
...  
Keyword(s):  
Atmospheric Circulation ◽  
Large Scale ◽  
The South ◽  
Synoptic Meteorology ◽  
South Eastern ◽  
East Pacific ◽  
Intensive Observations

Abstract. We present a descriptive overview of the meteorology in the south eastern Subtropical Pacific during the VOCALS-REx intensive observations campaign, which took place in October and November 2008. We provide a summary of the day-to-day meteorological and cloud conditions. Our main aim is to provide some broader spatial and temporal meteorological context for the measurements made during VOCALS-REx, attempting to link the large-scale conditions of the atmospheric circulation with the locally observed conditions, also with a view of estimating the representativity of the specific season that was sampled by VOCALS-REx.

scholarly journals AN ONLINE 3D DATABASE SYSTEM FOR ENDANGERED ARCHITECTURAL AND ARCHAEOLOGICAL HERITAGE IN THE SOUTH-EASTERN MEDITERRANEAN

2017 ◽  
Vol XLII-2/W3 ◽  
pp. 1-8 ◽  
Author(s):  
D. Abate ◽  
A. Avgousti ◽  
M. Faka ◽  
S. Hermon ◽  
N. Bakirtzis ◽  
...  
Keyword(s):  
Eastern Mediterranean ◽  
The South ◽  
Archaeological Heritage ◽  
Heritage Sites ◽  
South Eastern ◽  
Digital Heritage ◽  
Wide Range ◽  
Outstanding Universal Value ◽  
Computer Scientists ◽  
3D Database

The World Heritage Convention, drawn by various international bodies in 1972, was designed to protect cultural or natural places of outstanding universal value so that future generations may be able to enjoy them. Responding to these principles as well as to the Charter on the Preservation of Digital heritage (Vancouver, 2003), this multidisciplinary project, which involves archaeologists, art historians, conservators and computer scientists, aims to create an open access, 3D interactive online geo-database of endangered architectural and archaeological heritage in the South Eastern Mediterranean basin; a region of tremendous cultural importance whose rech heritage is unfortunately threatened by both natural and human factors. A wide range of 3D modelling and topographic techniques have been applied to create accurate reconstructions of heritage sites, enriched by a extensive array of metadata.

scholarly journals PROSPECTS FOR OIL AND GAS PRESENCE IN THE SOUTH-EASTERN PART OF THE INNER FLYSCH COVERS OF THE UKRAINIAN CARPATHIANS

2019 ◽  
Vol 4 (181) ◽  
pp. 5-16
Author(s):  
Myroslav PAVLYUK ◽  
Volodymyr SHLAPINSKY ◽  
Olesya SAVCHAK ◽  
Myroslav TERNAVSKY ◽  
Lyubov HUZARSKA ◽  
...  
Keyword(s):  
Seismic Data ◽  
Hydrothermal Fluid ◽  
Large Scale ◽  
Oil And Gas ◽  
Significant Rise ◽  
Gas Composition ◽  
The South ◽  
Eastern Sector ◽  
South Eastern ◽  
The Given

We have studied the Cretaceous and Paleogene flysch of the Duklya-Chornohora, Burkut, Rakhiv, Marmarosh and Pieniny covers that in the south-eastern sector of the Ukrainian Carpathians near the Romanian border (Hutsulian segment) distinguish themselves by very inclined overthrust. Spatially the given tectonic units are in so-called hydrothermal fluid, unfavourable on the whole as to the presence of hydrocarbons in it on a large scale. But, within its limits the plots, small in area, with hydrocarbon prevalence in the gas composition are distinguished. Prospects for gas presence in the region should be connected with those of them that spatially are drown to the Transcarpathian trough. One such section is the Velikobychkovk sector of the Monastyretsky sub-cover, where it is proposed to lay a parametric well 1-Velikiy Bychkov, in order to reveal the possible para-autochthon of the Vezhany sub-cover and the Paleogene of the Dilovetsky sub-cover. In addition, according to seismic data, a significant rise in the pre-flysch base is forecast in this section of the Carpathians under the Marmarosh cover. The roof of this foundation at the location of the recommended well 1-Velikiy Bychkov may be at a depth of 5000–5500 m. It may be represented by the youngest deposits of the pre-Alpine complex – the Triassic strata, industrially oil and gas saturated in the neighboring countries.

scholarly journals Mesoscale Simulation of Tropical Cyclones in the South Pacific: Climatology and Interannual Variability

2011 ◽  
Vol 24 (1) ◽  
pp. 3-25 ◽  
Author(s):  
Nicolas C. Jourdain ◽  
Patrick Marchesiello ◽  
Christophe E. Menkes ◽  
Jérome Lefèvre ◽  
Emmanuel M. Vincent ◽  
...  
Keyword(s):  
Interannual Variability ◽  
Tropical Cyclones ◽  
Large Scale ◽  
Southern Oscillation ◽  
Regional Scale ◽  
South Pacific ◽  
South Pacific Convergence Zone ◽  
Dimensional Structure ◽  
The South ◽  
Wide Range

Abstract The Weather Research and Forecast model at ⅓° resolution is used to simulate the statistics of tropical cyclone (TC) activity in the present climate of the South Pacific. In addition to the large-scale conditions, the model is shown to reproduce a wide range of mesoscale convective systems. Tropical cyclones grow from the most intense of these systems formed along the South Pacific convergence zone (SPCZ) and sometimes develop into hurricanes. The three-dimensional structure of simulated tropical cyclones is in excellent agreement with dropsondes and satellite observations. The mean seasonal and spatial distributions of TC genesis and occurrence are also in good agreement with the Joint Typhoon Warning Center (JTWC) data. It is noted, however, that the spatial pattern of TC activity is shifted to the northeast because of a similar bias in the environmental forcing. Over the whole genesis area, 8.2 ± 3.5 cyclones are produced seasonally in the model, compared with 6.6 ± 3.0 in the JTWC data. Part of the interannual variability is associated with El Niño–Southern Oscillation (ENSO). ENSO-driven displacement of the SPCZ position produces a dipole pattern of correlation and results in a weaker correlation when the opposing correlations of the dipole are amalgamated over the entire South Pacific region. As a result, environmentally forced variability at the regional scale is relatively weak, that is, of comparable order to stochastic variability (±1.7 cyclones yr−1), which is estimated from a 10-yr climatological simulation. Stochastic variability appears essentially related to mesoscale interactions, which also affect TC tracks and the resulting occurrence.

scholarly journals MODIS-derived interannual variability of the equilibrium-line altitude across the Tibetan Plateau

2016 ◽  
Vol 57 (71) ◽  
pp. 140-154 ◽  
Author(s):  
Marinka Spiess ◽  
Christoph Schneider ◽  
Fabien Maussion
Keyword(s):  
Tibetan Plateau ◽  
Large Scale ◽  
Equilibrium Line ◽  
Climate Indices ◽  
The Tibetan Plateau ◽  
Equilibrium Line Altitude ◽  
Winter Temperatures ◽  
Moderate Resolution ◽  
Moderate Resolution Imaging Spectroradiometer ◽  
Positive Correlations

Abstract.Using the Moderate Resolution Imaging Spectroradiometer (MODIS) Level 1 radiance Swath Data (MOD02QKM) with a spatial resolution of 250 m, we derive snowlines during July–September 2001–12 for several mountain ranges distributed across the Tibetan Plateau (TP). Radiance bands 1 and 2 are projected to the study area and processed automatically. The discrimination between snow and ice is done using a k-mean cluster analysis and the snowlines are delineated based on a fixed percentile of the snow-cover altitude. The highest transient snowline altitude is then taken as a proxy for the equilibrium-line altitude (ELA). In the absence of measured glaciological, meteorological or hydrological data, our ELA time series enable better understanding of atmosphere-cryosphere couplings on the TP. Interannual ELA variability is linked to local and remote climate indices using a correlation analysis. Southerly flow and higher temperatures are linked with a higher ELA in most regions. Eastern and Trans-Himalayan sites show positive correlations between winter temperatures and ELA. As winter temperatures are substantially below zero, this suggests an enhancement of winter sublimation as opposed to a reduction in accumulation. It appears that large-scale atmospheric forcing has varying and sometimes opposite influences on the annual ELA in different regions on the TP.

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