ICE: Interactions between Climate and Earth surface processes

Financially supported by the CIRM, our group organized a one-week workshop in Château-d’Œx (August 26-30, 2024), bringing together 30 international glaciologists to discuss recent advances in numerical modeling of glacier evolution under various climate scenarios . In recent years, the glaciological community has made significant progress in developing open-source models for projecting glacier dynamics. For example, these models have allowed the simulation of the reduction of Alpine glaciers, a study from our group. The global model OGGM (Open Global Glacier Model) has existed for several years, supporting a community of over 200 users with annual workshops since 2016. Since 2021, our team has also been developing the IGM model, integrating artificial intelligence to surpass computational limitations. With around 60 users worldwide, IGM is applied in various contexts. In this dynamic, this joint OGGM-IGM workshop is organized to bring together these two communities, foster exchanges, and shape the future of open-source glacier modeling. Primarily intended for PhD students and post-doctoral researchers in glacier modeling, this event covers a range of topics: data assimilation, paleoclimatic and global modeling, visualization techniques, data management, and model comparison. Each participant presents their work, and excursions around Château-d’Œx as well as social events will help create a collaborative and friendly environment.

This year we returned to Les Diablerets for our annual group retreat. We hiked from the Col des Mosses to Lac Lioson before pausing for lunch, whilst some of the group continued the hike back to Les Diablerets. The theme of this years retreat was work-life balance and how to prioritise effectively in an academic career – after the hike we had an interesting discussion that gave all of us a lot to reflect on.

The group has expanded a lot over the past 12 months, and it was great to welcome Tancrede, Sarah and Maxime who have recently joined/will soon join as post-docs. The PIs cooked dinner and many thanks to Samuel, Salome and Brandon for the cookies and cake that fuelled our competitive spirit in the post-dinner quiz and games…!

We are happy to welcome three new group members working on glacier modelling with the “Instructed Glacier Model” :

Kejdi Lleshi has a master in Geophysics obtained at Universite Grenoble Alpes, France, and did a master’s thesis in Grenoble on “Icequake localization using full wavefield time reverse imaging”. Kejdi starts his PhD on paleo glacier modelling using new Machine Learning emulation techniques.

Daniel Bonser has a master’s in physics obtained at the University of Exeter, UK, and did a master’s thesis on “Quantum Optimal Control to Decipher Avian Magnetoreception”. Daniel starts also a PhD in paleo glacier modelling that includes new ML acceleration techniques to explore long-time scales.

Samuel Cook has a PhD in Glaciology obtained from Cambridge in November 2020. Samuel got a 2-year-long postdoc from the faculty and will work on ML-aided inverse modelling to infer the basal conditions of glaciers, having spent the last two years working on data assimilation as a postdoc at IGE in Grenoble.

At the end of June, Leif, Xiaoxia, Audrey and Kathy went to the Vispa valley, Switzerland, for the first fieldwork of this year (which was also Kathy’s first geological expedition!) for Xiaoxia’s PhD research. Xiaoxia’s project is part of the ERC supported ICED project, which aims to investigate the timing of overdeepened valley formation and relate it to glacial/interglacial cycles using novel OSL and ESR thermochronometry. Samples were collected along the  Saas and Matter Vispa rivers to determine the  timing of valley incision. The trip started at the conjunction of the Rhone and Vispa valleys before migrating towards the Saas Vispa river valley- which is characterized by a deep valley. Although the original aim was to collect samples as close to the river as possible, most of the place were inaccessible. In the end, the team managed to successfully collect 11 samples which will be processed at the University of Lausanne in the next few months.

Ian Delaney has recently submitted a paper about modeling subglacial erosion and sediment transport. Here, he and group members Leif Anderson and Frederic Herman developed a two-dimensional model that erodes bedrock and transports sediment in response to hydraulic conditions and sediment availability below the glacier. 

Here are a couple of videos showing the model’s behavior as applied to Griesgletscher here in Switzerland. Hopefully, the accompanying manuscript will be available in the coming months. 

This video shows subglacial conditions such as the size of the subglacial channels, the water flow, and the water velocity as they respond to hydrological forcing. We also show the changes in routing that occur in the domain by evaluating the number of cells that feed into a cell (receiver cells). 

The second video shows the spatial distribution of subglacial water discharge and sediment discharge. The top panel shows the total water transport in sediment from the catchment and the response of the sediment thickness across the catchment to sediment transport. 

Please feel free to contact Ian about the research at ianarburua.delaney@unil.ch.

Updated 20.10.23:

Christoph and Georgina are looking for a PhD candidate to work on a global Quaternary sediment dynamics!

Wind-blown deposits accumulate under specific climatic conditions, and therefore provide valuable archives of palaeoenvironmental change. Over the past few decades, an enormous amount of data has been generated constraining these records (timing of deposition, environmental properties). In this project, we seek to create a database of these data and to apply innovative data mining techniques to explore patterns of global palaeoenvironmental change.

The ideal candidate will have experience of quantitative geoscience and/or data science, with programming skills in R/MATLAB or similar and GIS/Spatial data analysis skills. An interest in palaeoenvironmental change is essential. Deadline is November 15th 2023 and applications must be made via the UNIL jobs portal here.

Last week many members of ICE participated in the first virtual Luminescence and Electron Spin Resonance Dating (LED) conference. The conference organisers did a fantastic job of creating a dynamic online event, comprising a combination of zoom sessions, pre-recorded oral and poster presentations and the opportunity to discuss and socialise with colleagues via GatherTown. All of the PhD students did brilliantly at presenting their research, including Yuni and Xiaoxia who started earlier this year.

Yuni presented preliminary results of luminescence dating on fluvial sediments from Indonesia, whilst Xiaoxia presented her first ESR dose response curves for samples collected at Sion, which she is using to develop the ESR-thermochronometry technique. Chloé showed why the choice of temperatures for isothermal decay measurements is crucial for deriving robust thermal kinetic parameters from feldspar minerals, whilst Joanne presented her first luminescence palaeothermometry ages from Gornergrat, Zermatt. Joanne’s presentation was very well received by the community and she was awarded the Ann Wintle prize for best application – congratulations Joanne!

In addition to the PhD students, the senior researchers from ICE were also very active. Melanie presented her final results from exploring the effect of chemical weathering on the luminescence properties of feldspar, whilst Christoph presented his initial results from trying to apply rock surface exposure dating to pebbles from the Nazca lines in Peru.

The next LED meeting will take place in Denmark in 2023 – we are really looking forward to seeing our colleagues again in person and to discussing the latest developments in luminescence and ESR dating together then.

Joanne’s latest work on reducing variation in OSL rock surface dating profiles is to be published in Quaternary Geochronology! Through numerous experiments, her paper explores the influence of various measurement parameters on scatter observed in OSL-depth profiles measured from rock surfaces exposed in Zermatt, Switzerland. The results of the study highlight the potential impact of thermal lag, and concludes by suggesting that future OSL rock surface dating studies place samples in metal cups, reduce heating rates and increase preheating and holding times to minimise this effect.

You can read Joanne’s article here.