ALBERT

All Library Books, journals and Electronic Records Telegrafenberg

feed icon rss

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
  • 1
    Publication Date: 2023-02-08
    Description: Abstract
    Description: This data publication is supplementary to the study on headwall erosion rates at Glacier d'Otemma in Switzerland, by Wetterauer et al. (2022). Debris on glacier surfaces stems from steep bedrock hillslopes that tower above the ice, so-called headwalls. Recently, rock walls in high-alpine glacial environments experience increased destabilization due to climate warming. Since supraglacial debris alters the melt behaviour of the ice underneath, increased headwall erosion and debris delivery to glacier surfaces will modify glacial mass balances. Therefore, we expect that the response of glaciers to climate change is likely linked to how headwall erosion responds to climate change. As headwall debris is deposited on the ice surface of valley glaciers it is passively transported downglacier, both supra- and englacially. Where two glaciers join, debris along their margins is merged to form medial moraines. Since medial moraine debris tends to be older downglacier, systematic downglacier-sampling of medial moraine debris and the measurement of in situ-produced cosmogenic 10Be concentrations ([10Be]) hold the potential to assess long-term (〉10^2-10^4 yrs) headwall erosion rates through time. However, to obtain the cosmogenic signals of headwall erosion, [10Be] within supraglacial debris need to be corrected for glacial transport time, as cosmogenic nuclides continue to accumulate during exposure and transport. This additional 10Be accumulation during debris transport can be accounted for by simple downglacier debris trajectory modelling. Providing our 10Be dataset together with detailed information on our 1-D modelling approach is the main objective of this data publication. The data is presented as one single xlsx-file with three different tables. A detailed description of the sample processing and the debris trajectory model are provided in the data description file of this data publication. For more information see our study Wetterauer et al. (2022).
    Description: Other
    Description: The data were collected as part of the project “COLD”, which investigates the Climate Sensitivity of Glacial Landscape Dynamics with a focus on the European Alps. This research receives funding from the European Research Council (ERC) under the European Union's Horizon 2020 research and innovation program under grant agreement 759639.
    Keywords: Alpine glaciers ; medial moraines ; cosmogenic 10Be ; grain size ; headwall erosion rates ; supraglacial debris ; EARTH SCIENCE 〉 LAND SURFACE 〉 EROSION/SEDIMENTATION 〉 EROSION ; EARTH SCIENCE 〉 SOLID EARTH 〉 GEOCHEMISTRY 〉 GEOCHEMICAL PROPERTIES 〉 CHEMICAL CONCENTRATIONS ; EARTH SCIENCE 〉 SOLID EARTH 〉 GEOCHEMISTRY 〉 GEOCHEMICAL PROPERTIES 〉 ISOTOPES ; EARTH SCIENCE 〉 SOLID EARTH 〉 GEOMORPHIC LANDFORMS/PROCESSES 〉 GLACIAL LANDFORMS 〉 MORAINES 〉 MEDIAL MORAINE
    Type: Dataset , Dataset
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 2
    Publication Date: 2023-12-20
    Description: Abstract
    Description: At valley glaciers, rockwall erosion supplies debris to glacier surfaces. Once deposited on the ice, rockwall debris is passively entrained and becomes part of the glacial system, e.g., forming medial moraines as downglacier transport continues. Where debris occurs supraglacial, it modifies ice ablation and, thus, changes in rockwall erosion and debris supply rates modify glacial debris cover and mass balance and may affect glacier retreat in response to climate change. Yet, estimates on rockwall erosion rates close to glacier surfaces are few and quantifying spatiotemporal supply patterns is not trivial. This data publication is supplementary to the study on rockwall erosion rates at five Swiss valley glaciers around Pigne d’Arolla, by Wetterauer & Scherler (2023). We temporally and spatially assess rockwall erosion by measuring in situ-produced cosmogenic 10Be concentrations ('[10Be]measured') in medial moraine debris, which we systematically sampled along downglacier-profiles, and by comparing records from various medial moraines, which are supplied by rockwalls differing in exposure and morphology. However, as '[10Be]measured' within supraglacial debris is the sum of '[10Be]rockwall', accumulated during rockwall erosion, and '[10Be]transport', accumulated during post-depositional downglacier transport, medial moraine '[10Be]measured' should be corrected for '[10Be]transport'. If glacier velocities through time are known, '[10Be]transport' can be estimated by downglacier debris trajectory modelling. Providing our 10Be dataset and ~40-year records of glacier surface velocities from four of the five valley glaciers (Glacier du Brenay, Glacier de Cheilon, Glacier de Pièce, Glacier de Tsijiore Nouve) is the main objective of this data publication. The dataset of the fifth glacier (Glacier d’Otemma) has already been published as case study by Wetterauer et al. (2022a,b).
    Description: Other
    Description: The data were collected as part of the project “COLD”, which investigates the Climate Sensitivity of Glacial Landscape Dynamics with a focus on the European Alps. This research receives funding from the European Research Council (ERC) under the European Union's Horizon 2020 research and innovation program under grant agreement 759639.
    Keywords: Alpine glaciers ; medial moraines ; cosmogenic 10Be ; rockwall erosion rates ; supraglacial debris ; glacier surface velocities ; boulder tracking ; EARTH SCIENCE 〉 LAND SURFACE 〉 EROSION/SEDIMENTATION 〉 EROSION ; EARTH SCIENCE 〉 SOLID EARTH 〉 GEOCHEMISTRY 〉 GEOCHEMICAL PROPERTIES 〉 CHEMICAL CONCENTRATIONS ; EARTH SCIENCE 〉 SOLID EARTH 〉 GEOCHEMISTRY 〉 GEOCHEMICAL PROPERTIES 〉 ISOTOPES ; EARTH SCIENCE 〉 SOLID EARTH 〉 GEOMORPHIC LANDFORMS/PROCESSES 〉 GLACIAL LANDFORMS 〉 MORAINES 〉 MEDIAL MORAINE
    Type: Dataset , Dataset
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 3
    Publication Date: 2022-10-04
    Description: Climate change affects the stability and erosion of high‐alpine rock walls above glaciers (headwalls) that deliver debris to glacier surfaces. Since supraglacial debris in the ablation zone alters the melt behaviour of the underlying ice, the responses of debris‐covered glaciers and of headwalls to climate change may be coupled. In this study, we analyse the beryllium‐10 (10Be)‐cosmogenic nuclide concentration history of glacial headwalls delivering debris to the Glacier d'Otemma in Switzerland. By systematic downglacier‐profile‐sampling of two parallel medial moraines, we assess changes in headwall erosion through time for small, well‐defined debris source areas. We compute apparent headwall erosion rates from 10Be concentrations ([10Be]), measured in 15 amalgamated medial moraine debris samples. To estimate both the additional 10Be production during glacial debris transport and the age of our samples we combine our field‐based data with a simple model that simulates downglacier debris trajectories. Furthermore, we evaluate additional grain size fractions for eight samples to test for stochastic mass wasting effects on [10Be]. Our results indicate that [10Be] along the medial moraines vary systematically with time and consistently for different grain sizes. [10Be] are higher for older debris, closer to the glacier terminus, and lower for younger debris, closer to the glacier head. Computed apparent headwall erosion rates vary between ~0.6 and 10.8 mm yr−1, increasing over a maximum time span of ~200 years towards the present. As ice cover retreats, newly exposed headwall surfaces may become susceptible to enhanced weathering and erosion, expand to lower elevations, and contribute formerly shielded bedrock of likely different [10Be]. Hence, we suggest that recently lower [10Be] reflect the deglaciation of the debris source areas since the end of the Little Ice Age.
    Description: In glacial landscapes, systematic downglacier‐sampling of medial moraine debris holds the potential to assess changes in headwall erosion through time. Cosmogenic beryllium‐10 (10Be) concentrations within the medial moraines of Glacier d'Otemma, Switzerland, broadly increase downglacier and translate into increasing headwall erosion rates towards the present. These trends may reflect processes associated with the exposure of new bedrock surfaces across recently deglaciating source headwalls.
    Description: European Research Council (ERC) H2020‐EU.1.1.
    Description: https://doi.org/10.5880/GFZ.3.3.2021.007
    Keywords: ddc:551
    Language: English
    Type: doc-type:article
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...