Introduction to the 'Weathering Crust' team

The weathering crust (or "WC") team, led by Prof Martyn Tranter, are based at Aarhus University and are responsible for measuring, monitoring and modelling ice surface change. This includes all processes that affect the albedo (brightness) of the surface and control how rapidly the ice melts. Of particular importance are the changing architecture of the surface “weathering crust” – a thin porous layer that forms seasonally across the Greenland Ice Sheet’s melting zone, the accumulation of light-absorbing glacier algae, and the drainage of melt water towards the sea. These processes are interlinked in complex ways and determine the contribution of the ice sheet to global sea levels. The team is currently made up of four researchers:

 Dr Joseph Cook (Senior Researcher)

Joseph is responsible for the overall work package strategy and has particular expertise in albedo measurement and modelling. He has developed the BioSNICAR models for calculating the albedo-reducing effects of glacier algae and published extensively on the interactions between biological and  physical processes on ice surfaces. His field work experience includes >15 on-ice camps in Greenland in all seasons and he has explored deep beneath the ice sheet surface in a series of ice caving expeditions.

Shunan Feng (PhD student)

Shunan is interested in understanding the process and climate response of earth surface, particularly time series analysis by combining in-situ measurements, remote sensing and other geospatial data. This had led him to focus on remote sensing during his bachelor study and specialize in glaciology during master study in Uppsala University. He also worked as remote sensing associate in the International Committee of the Red Cross. His role in Deep Purple will be trying to monitor the variability of the albedo and biogeoprocessing of rotting ice surfaces in the Dark Zone of the Greenland Ice Sheet at different scales. The understanding of the albedo evolution of the GrIS will require unprecedented spatial, spectral and temporal resolution datasets from the ground and the air, new techniques for bridging across spatial scales and advanced analytical techniques for spatiotemporal changes. Novel algorithms of albedo calculation, methods of spectral analysis in detecting, classifying the glacier algae and estimating the pigment concentration etc. will be experimented to link the variation of albedo with glacier algae growth. We will try to bridge the gap between field measurement, UAV, and various satellite platform and upscale the optimized methods to large area.

Lou Chevrollier (PhD student)

Lou studied energy and environmental engineering in France before finding her way into natural sciences. She is interested in micro scale processes and before joining the DP project, she has been working with plankton and metal pollution combining modelling and field-oriented methods. She is also fascinated by light interactions, from the diffraction patterns on butterfly wings to the atmospheric particle scattering coloring the sky in blue and the high reflectivity of cryospheric surfaces, blinding us when hiking in mountains. In the WC group, she will be looking into the small scale processes driving albedo variability, trying to disentangle the role of the different light absorption particles (LAPs) and weathered crust dynamics in the darkening, combining field measurements and modelling experiments. In particular, she will work on refining numerical models to better reproduce and understand the role of glacier algae among the other light absorbing particles and within the changing ice structure.

Dr Ian Stevens (Postdoc)

Ian completed his PhD exploring the eco-hydrology of glacial surfaces at Aberystwyth University, studying the physical parameters of the near-surface weathering crust and the microbial abundance of surface meltwaters at field sites across the Northern Hemisphere from the high Arctic to the European Alps. His research interest focuses on elucidating hydrological processes within the weathering crust, exploring water, particulate and microbial fluxes through this aquifer to the channelised supraglacial hydrological system. To achieve this goals, Ian has a passion for method development, including designing and building custom sensors to measure previously unrecorded parameters. Ian’s role in DEEP PURPLE will be to continue to obtain empirical measurements of the weathering crust, informing modelling and upscaling approaches, and enabling assessment the provision of water to ice-surface algae.