Our work tackles a range of research questions, across the globe and across timescales. We have three primary themes: ice-climate interactions, ice sheet processes, and landscape evolution.
The cryosphere — the frozen components of Earth's system — is inherently linked to the climate. Our work investigates how glaciers and ice sheets respond to anthropogenic and natural climate variability.
We are particularly interested in the relationship between the atmosphere and the surface mass balance of ice sheets and temperate glaciers, and the oceanic processes that drive ice sheet advance and retreat.
Ice Sheet Processes
The flow of ice, and the dynamic response of glaciers and ice sheets to changes in the climate, are dependent on several fundamental processes. Our research aims to better understand such processes.
We are particularly interested in the roles of basal sliding, ice deformation, bed topography and ice shelf buttressing in limiting or enhancing ice mass loss, and the timescales over which they are important.
A landscape is the product of multiple geological processes that act on a range of timescales. Our work looks to better understand how glacial, climatic and tectonic processes modify the landscape.
We are particularly interested in erosion and elevation change in polar and alpine regions, and the relationship with glaciers and ice sheets.
We use a combination of approaches in our research. These are primarily focused around observations, numerical modelling and geochronology.
An important part of our work involves the collection and analysis of observational data from glaciers and ice sheets in various parts of the globe.
In Antarctica, we assess modern ice sheet changes from satellite observations, survey the present-day thickness of the ice sheet (ICECAP), and collect geological data from the ice sheet margins.
This information is used to determine past and present changes in the size of the ice sheet, and as inputs to our ice sheet models.
Geochronology comprises a number of techniques to determine the age of rocks and events in the geological past.
Our principle approach is cosmogenic nuclide exposure dating, which we use to constrain past changes in the size of glaciers and ice sheets.
In 2021, we will have a new purpose-built cosmogenic nuclide laboratory to carry out our geochemistry.
A selection of publications from our team.
Regional-scale abrupt Mid-Holocene ice sheet thinning in the western Ross Sea, Antarctica
Jones, R.S.*, Whitmore, R.J.*, Mackintosh, A.N., Norton, K.P., Eaves, S.R., Stutz, J. and Christl, M. (*Joint-lead)
The length of modern observations is too short to confidently evaluate how bed topography influences ice sheet response to climate warming on centennial time scales. In this study, cosmogenic exposure records of ice sheet thinning demonstrate that a regional-scale Antarctic ice loss event occurred in the Mid-Holocene. An episode of abrupt glacier thinning is shown to be near-identical in timing, rate and magnitude to that recorded at another glacier 100 km away. The data indicate that ocean warming most likely drove grounding-line retreat and ice drawdown, which then accelerated as a result of marine ice sheet instability.
Anthropogenic warming forces extreme annual glacier mass loss
Vargo, L.J., Anderson, B.A., Dadić, R., Horgan, H.J., Mackintosh, A.N., King, A.D. & Lorrey, A.M.
Nature Climate Change
Direct links between human-induced climate warming and extreme glacier mass-loss years have not yet been documented. In this study, event attribution methods and glacier mass balance modelling is applied across New Zealand’s Southern Alps. Extreme mass loss is estimated to be at least six times (2011) and ten times (2018) (>90% confidence) more likely to occur with anthropogenic forcing than without. These results suggest that there will be an increasingly visible human fingerprint on extreme glacier mass-loss years in the coming decades.
Southern Ocean carbon sink enhanced by sea-ice feedbacks at the Antarctic Cold Reversal
Fogwill, C.J., Turney, C.S.M., Menviel, L., ..., Mackintosh, A., ..., Cooper, A.
The Southern Ocean occupies 14% of the Earth’s surface and plays a fundamental role in the global carbon cycle and climate. Using a highly resolved horizontal ice core and transient climate modelling, this study indicates that sea-ice biological feedbacks enhanced CO2 sequestration and created a substantial regional marine carbon sink, which contributed to the plateau in CO2 during the ACR.
Totten Glacier subglacial hydrology determined from geophysics and modeling
Dow, C.F., McCormack, F.S., Young, D.A., Greenbaum, J.S., Roberts, J.L. and Blankenship, D.D.
Earth and Planetary Science Letters
The subglacial hydrology of the Aurora Subglacial Basin, East Antarctica, was investigated using the GlaDS subglacial hydrology model. A distributed hydrological system was simulated in the deep interior of the basin with a highly channelised system in the approach to the Totten Glacier grounding line. The results highlight the role of basal hydrology in influencing ice dynamics, particularly close to the grounding line in a region that is key for glacier stability.