Reconstruction of LGM ice extents in Europe indicates a cold and dry climate with precipitation patterns similar to present day

2020 ◽  
Author(s):  
Vjeran Višnjević ◽  
Frederic Herman ◽  
Günther Prasicek
Keyword(s):  
Precipitation Pattern ◽  
Mountain Range ◽  
Ice Flow ◽  
Last Glacial Period ◽  
Temperature And Precipitation ◽  
Westerly Winds ◽  
The Alps ◽  
Precipitation Changes ◽  
Climate Proxies ◽  
The Last Glacial

<p> </p><p>During the pinnacle of the last glacial period 21 kyr ago, the Alps and the Pyrenees were largely covered by ice. Climate was colder and most likely drier, but the magnitudes of temperature and precipitation changes remain poorly constrained. This is in part because climate proxies are not sufficiently accurate, and because there are unknowns on the past position of the Westerly winds and, consequently, the intensity of the moisture flow towards Europe. A new inverse method combined with an ice flow model enables us to infer past climate from mapped ice extents. In the case of the Alps, all of the presented scenarios recover an increase in the position of the ELA across the mountain range from west to east, and a decrease from north to south, pointing to a dominantly zonal circulation with Westerlies bringing moisture from the Atlantic. This is supported by the Pyrenees reconstruction, where the method recovers a clear N-S gradient for all scenarios, indicating that the moisture source from the direction of the Atlantic. While the precipitation pattern was probably not much different from today, mean temperatures were ~9.3 ± 2.97˚C lower in the Alps and ~6.6 ± 1.6˚C lower in the Pyrenees. Our results match pollen-based reconstructions if the climate was 60% dryer than today.</p><p> </p>

scholarly journals Species rediscovery or lucky endemic? Looking for the supposed missing species Leistus punctatissimus through a biogeographer’s eye (Coleoptera, Carabidae)

ZooKeys ◽  
2018 ◽  
Vol 740 ◽  
pp. 97-108
Author(s):  
Pizzolotto Roberto ◽  
Brandmayr Pietro
Keyword(s):  
Climate Change ◽  
Endemic Species ◽  
Ecological Factors ◽  
Type Locality ◽  
Suitable Habitat ◽  
Mountain Range ◽  
Glacial Period ◽  
Last Glacial Period ◽  
Last Glacial ◽  
The Last Glacial

Is it correct to look for a supposedly missing species by focusing research at the type locality? A species can be declared extinct because for an unusual amount of time it has not been seen again; however, in the frame of the climate change it is likely that a supposedly missing species is a lucky survivor not seen because it was not searched for in the correct environment. We used the strictly endemic Leistus punctatissimus Breit, 1914 (Coleoptera, Carabidae) as the case study for testing the latter hypothesis vs. the type locality approach. On the basis of past unsuccessful searches in the Dolomites (a mountain range in the eastern Alps, Italy) driven by the type locality approach, a study area was selected where climate change may have exerted environmental constraints on endemic species. Five pitfall traps were used in each of seven sample sites, at an average altitude of 2600 m a.s.l., within a high altitude alpine plateau covered by scarce patchy vegetation. Leistus punctatissimus was rediscovered, far from its type locality, after one hundred years since its first collection. It was part of a group of species well adapted to the extreme ecological factors of the alpine environments above the vegetation line. Following a biogeographical approach (i.e., the biogeographer’s eye rather than the collector’s eye) it was possible to find an endemic species of the alpine ecological landscape in places from where it probably had never disappeared. The supposed refugial area was a nunatak during the last glacial period, where Leistus punctatissimus found suitable habitat conditions, and from where it alternated between downward and uphill changes in its distribution range after the last glacial period, under the effect of climate change. From such a perspective, it can be concluded that the type locality may be the wrong place to look for a supposedly extinct species.

A Comparison of Deep Antarctic Ice Cores and Their Implications for Climate Between 65,000 and 15,000 Years Ago

1989 ◽  
Vol 31 (2) ◽  
pp. 135-150 ◽  
Author(s):  
J. Jouzel ◽  
G. Raisbeck ◽  
J.P. Benoist ◽  
F. Yiou ◽  
C. Lorius ◽  
...  
Keyword(s):  
Ice Cores ◽  
Gas Content ◽  
Precipitation Rate ◽  
Glacial Period ◽  
Last Glacial Period ◽  
Last Glacial ◽  
Temperature And Precipitation ◽  
Elevation Changes ◽  
Antarctic Continent ◽  
The Last Glacial

AbstractThree ice cores drilled in the central part of the Antarctic continent extend back to the last glacial period: one from West Antarctica (Byrd) and two from East Antarctica (Vostok and Dome C). This period is also partly covered by a few cores from the coastal areas. In these cores, climatic information is mostly derived from the isotopic profiles (δD or δ18O) from which surface temperature and, more indirectly, precipitation rate can be estimated. The main objective has been to compare thoroughly the three deep ice cores for the main part of the last glacial period (from ca. 65,000–15,000 yr B.P.). The time scales have been examined in detail and a new 40,000 yr chronology for the Dome C core adopted. Special emphasis is placed on the link between the concentration of 10Be and past accumulation changes and on the use of peaks in the concentration of this cosmogenic isotope as stratigraphic markers. Elevation changes of the ice sheet, derived from gas content and isotopic data, bear directly on interpretations of past temperature and precipitation rate changes.

scholarly journals Climatic and glaciological information inferred from air-content measurements of a Law Dome (East Antarctica) ice core

1999 ◽  
Vol 45 (150) ◽  
pp. 255-263 ◽  
Author(s):  
Marc Delmotte ◽  
Dominique Raynaud ◽  
Vin Morgan ◽  
Jean Jouzel
Keyword(s):  
Ice Core ◽  
East Antarctica ◽  
Seasonal Temperature ◽  
Last Deglaciation ◽  
Last Glacial Period ◽  
Annual Variations ◽  
Air Content ◽  
Temperature And Precipitation ◽  
Elevation Changes ◽  
The Last Glacial

AbstractThe total air content(V)of ice has been measured along the Dome Summit South (DSS) core from Law Dome, East Antarctica. The main features of this record are the very well-preserved sub-annual fluctuations ofV(down to at least 900 m depth) and the significant increase of theVvalues during the last deglaciation. The sub-annual variations reflect changes in close-off porosity, and we interpret theVseasonal peaks as tracers of depth-hoar layers. For the longer time-scale, the largeVfluctuations observed are interpreted in terms of elevation and/or close-off porosity changes under different assumptions. We analyze the possible influence of a different global pressure field and/or a change in seasonal temperature and precipitation cycles during the last glacial period. Our estimates of surface elevation changes derived from theVdata are then compared with independent reconstructions of past elevations.

scholarly journals Species rediscovery or lucky endemic? Looking for the supposed missing species Leistus punctatissimus through a biogeographer’s eye (Coleoptera, Carabidae)

ZooKeys ◽  
2018 ◽  
Vol 740 ◽  
pp. 115-126 ◽  
Author(s):  
Roberto Pizzolotto ◽  
Pietro Brandmayr
Keyword(s):  
Climate Change ◽  
Endemic Species ◽  
Ecological Factors ◽  
Type Locality ◽  
Suitable Habitat ◽  
Mountain Range ◽  
Glacial Period ◽  
Last Glacial Period ◽  
Last Glacial ◽  
The Last Glacial

Is it correct to look for a supposedly missing species by focusing research at the type locality? A species can be declared extinct because for an unusual amount of time it has not been seen again; however, in the frame of the climate change it is likely that a supposedly missing species is a lucky survivor not seen because it was not searched for in the correct environment. We used the strictly endemic Leistuspunctatissimus Breit, 1914 (Coleoptera, Carabidae) as the case study for testing the latter hypothesis vs. the type locality approach. On the basis of past unsuccessful searches in the Dolomites (a mountain range in the eastern Alps, Italy) driven by the type locality approach, a study area was selected where climate change may have exerted environmental constraints on endemic species. Five pitfall traps were used in each of seven sample sites, at an average altitude of 2600 m a.s.l., within a high altitude alpine plateau covered by scarce patchy vegetation. Leistuspunctatissimus was rediscovered, far from its type locality, after one hundred years since its first collection. It was part of a group of species well adapted to the extreme ecological factors of the alpine environments above the vegetation line. Following a biogeographical approach (i.e., the biogeographer’s eye rather than the collector’s eye) it was possible to find an endemic species of the alpine ecological landscape in places from where it probably had never disappeared. The supposed refugial area was a nunatak during the last glacial period, where Leistuspunctatissimus found suitable habitat conditions, and from where it alternated between downward and uphill changes in its distribution range after the last glacial period, under the effect of climate change. From such a perspective, it can be concluded that the type locality may be the wrong place to look for a supposedly extinct species.

scholarly journals Modelling last glacial cycle ice dynamics in the Alps

2018 ◽  
Author(s):  
Julien Seguinot ◽  
Guillaume Jouvet ◽  
Matthias Huss ◽  
Martin Funk ◽  
Susan Ivy-Ochs ◽  
...  
Keyword(s):  
Last Glacial Maximum ◽  
Ice Sheet ◽  
Glacial Maximum ◽  
Climate Forcing ◽  
European Alps ◽  
Glacial Cycle ◽  
Ice Flow ◽  
Last Glacial ◽  
The Alps ◽  
The Last Glacial

Abstract. The European Alps, cradle of pioneer glacial studies, are one of the regions where geological markers of past glaciations are most abundant and well-studied. Such conditions make the region ideal for testing numerical glacier models based on simplified ice flow physics against field-based reconstructions, and vice-versa. Here, we use the Parallel Ice Sheet Model (PISM) to model the entire last glacial cycle (120–0 ka) in the Alps, using horizontal resolutions of 2 and 1 km and up to 576 processors. Climate forcing is derived using present-day climate data from WorldClim and the ERA-Interim reanalysis, and time-dependent temperature offsets from multiple palaeo-climate proxies, among which only the EPICA ice core record yields glaciation during marine oxygen isotope stages 4 (69–62 ka) and 2 (34–18 ka) spatially and temporally consistent with the geological reconstructions, while the other records used result in excessive early glacial cycle ice cover and a late Last Glacial Maximum. Despite the low variability of this Antarctic-based climate forcing, our simulation depicts a highly dynamic ice sheet, showing that Alpine glaciers may have advanced many times over the foreland during the last glacial cycle. Ice flow patterns during peak glaciation are largely governed by subglacial topography but include occasional transfluences and self-sustained ice domes. Modelled maximum ice surface is 861 m higher than observed trimline elevations in the upper Rhone Valley, yet our simulation predicts little erosion at high elevation due to cold-based ice. Finally, the Last Glacial Maximum advance, often considered synchronous, is here modelled as a time-transgressive event, with some glacier lobes reaching their maximum as early as 27 ka, and some as late as 21 ka.

scholarly journals Climatic and glaciological information inferred from air-content measurements of a Law Dome (East Antarctica) ice core

1999 ◽  
Vol 45 (150) ◽  
pp. 255-263 ◽  
Author(s):  
Marc Delmotte ◽  
Dominique Raynaud ◽  
Vin Morgan ◽  
Jean Jouzel
Keyword(s):  
Ice Core ◽  
East Antarctica ◽  
Seasonal Temperature ◽  
Last Deglaciation ◽  
Last Glacial Period ◽  
Annual Variations ◽  
Air Content ◽  
Temperature And Precipitation ◽  
Elevation Changes ◽  
The Last Glacial

AbstractThe total air content (V) of ice has been measured along the Dome Summit South (DSS) core from Law Dome, East Antarctica. The main features of this record are the very well-preserved sub-annual fluctuations of V (down to at least 900 m depth) and the significant increase of the V values during the last deglaciation. The sub-annual variations reflect changes in close-off porosity, and we interpret the V seasonal peaks as tracers of depth-hoar layers. For the longer time-scale, the large V fluctuations observed are interpreted in terms of elevation and/or close-off porosity changes under different assumptions. We analyze the possible influence of a different global pressure field and/or a change in seasonal temperature and precipitation cycles during the last glacial period. Our estimates of surface elevation changes derived from the V data are then compared with independent reconstructions of past elevations.

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