DR JONATHAN CARRIVICK
PROJECTS & WORK IN PROGRESS
Modelling rapid landscape change due to outburst floods
(with collaborators in the UK, Iceland and New Zealand)
Outburst floods are a sudden release and advancing kinematic wave of water and sediment, with a peak discharge that is often several orders of magnitude greater than perennial flows. This project will provide data on transient phenomena within outburst floods. Specifically it will consider controls on outburst flood conveyance (i.e. the hydraulic evolution downstream) and resultant erosion and deposition patterns and characteristics. Particular controls to be examined are mobility of pre-existing sediment, bed roughness, flow sediment concentration and hydrograph shape. This will be examined in a series of flume experiments, in the Sorby Environmental Fluid Dynamics Laboratory (SEFDL).
Explicit quantification of water-sediment processes within outburst floods is essential for several reasons: 1. Outburst floods occur worldwide and are a natural hazard to life, property and infrastructure. 2. Although all outburst floods are a mix of water and sediment, models that fully integrate both are unreported. 3. Whilst sources of outbursts and trigger mechanisms of dam breaches are well known, flow behaviour is not, largely because of the inherent problems of directly measuring such sudden, powerful and rapidly-varying flows. Prediction of flow character is therefore currently impossible. 4. Management solutions to mitigate for outburst floods can only be produced when processes governing flow behaviour are well understood; i.e. parameterised and numerically modelled, and that model is validated against real-world data. These criteria must arise from an integrated and sustainable design approach. 5. Given climate change, there is a very real potential for alterations in air temperature and precipitation patterns to cause an increased frequency of ice- and moraine-dammed lake outbursts and landslide-triggered outbursts, and an increased magnitude of rainfall-induced outburst floods, for example. 6. Many outburst floods are sourced from natural lakes that are a water resource.
This project is funded by a NERC New Investigators Research Grant
Multi-scale changes in glaciation of the Antarctic Peninsula
( with Prof. Neil Glasser, Dr Bethan Davies, Prof. Mike Hambrey and Prof. John Smellie)
The main aim of this AFI project is to reconstruct the glacial history of the NE Antarctic Peninsula over centennial to millennial timescales. We have focused on the timing and style of post Last Glacial Maximum (LGM) retreat along the eastern margin of the Antarctic Peninsula Ice Sheet. During the Last Glacial Maximum, circa 18 cal. ka BP, ice draining from northeast Trinity Peninsula and from an ice dome over James Ross Island coalesced in Prince Gustav Channel. These glaciers formed a palaeo-ice stream flowing northwards and southwards to the shelf edge, resulting in an ice divide off northwest James Ross Island. However, the onshore interaction of Antarctic Peninsula-derived ice and an extended Mount Haddington Ice Cap on James Ross Island remains uncertain, and chronostratigraphy is poor, being largely based on radiocarbon dates, which are influenced by the large marine reservoir effect.
The principal outputs from a recent seven-week field season on the Ulu Peninsula, James Ross Island, are (1) a detailed geomorphological and sedimentological map of the Ulu Peninsula and (2) samples from granite erratic boulders for cosmogenic nuclide exposure age dating. Provisional mapping shows that the Ulu Peninsula has previously been overwhelmed by ice originating from Trinity Peninsula, depositing granitic erratics across the island. In coastal areas, these erratics are associated with glacial drifts containing numerous smaller Trinity Peninsula erratics. A key question is the age of the glacial incursion that deposited the granite erratics on the Ulu Peninsula. Two possibilities exist; (1) they represent an overriding Antarctic Peninsula Ice Sheet during the LGM, or (2) the Prince Gustav Ice Stream effectively isolated James Ross Island from Antarctic Peninsula ice, and these erratic boulders date from a pre-LGM glaciation. Cosmogenic nuclide exposure ages on these granite erratics will provide important information regarding Antarctic Peninsula ice stream dynamics during the LGM.
This project is funded by an Antarctic Funding Initiative (AFI) NERC Research Grant
Modelling Arctic Alpine glacier mass balance and runoff
(with Dr Dave Rippin)
The aims of this project are to i) reconstruct historical and modern mass balance of Kårsavagge, near Abisko, arctic Sweden, and ii) to infer the evolving dynamical and thermal regime of that glacier.
Briefly, this will involve the following field measurements; (i) a topographic survey of Kårsaglaciären surface topography (dGPS) and snow-ice interface (snow probing), (ii) GPR measurements of depth of ice to bedrock, (iii) collation of existing mass balance (via Tarfala/Stockholm) and climate records (via Abisko), (iv) Kårsavagge weather parameters (for energy balance modelling validation).
It is envisaged that this project will ultimately provide the basis for understanding the hydrological implications of regional climate change by quantifying winter snow melt events and spring snowpack retreat. This will be achieved by modelling the effects of air temperature and precipitation on glacial mass balance and runoff and river discharge (from glacial and groundwater sources). We are also interested in how cold based glaciers respond to dynamical thinning due to warming air temperatures.
This project is funded by The Royal Swedish Academy of Sciences’ Transnational Access Programme (ATANS), an EU-FP7 INTERACT logistics grant, the Royal Geographical Society (RGS) Peter Fleming award, a Royal Society Research Grant and by a NERC PhD studentship to Chris Williams.
Alpine glacier runoff and floodplain dynamics
(with Martin Geilhausen and Dr Lee Brown)
This project is complimentary to that being undertaken in Abisko, arctic Sweden (above). We are examining the Odenwinkelkees Glacier and its associated braidplain, in central Austria. We aim to examine the potential for linking glacier mass balance and runoff models with river hydraulic simulations to predict floodplain expansion and contraction cycles.
Using our knowledge of the Odenwinkelkees site, we are integrating research and teaching through online, on-demand access to telemetry-enabled field dataloggers. This project is funded by the University of Leeds Academic Development Fund and will integrate world-class research with undergraduate and taught masters learning. Specifically, we aim to enable real-time (online/on-demand) access to research-grade meteorological and hydrological data from a glacierized alpine catchment in Austria. Environmental sensors will be linked to automatic dataloggers with a telemetry facility. Students and staff will thus be able to obtain instantaneous and recorded data from these sensors via an internet connection, using a Global System for Mobile communications (GSM) link.
This project is supported by a EUFAR airborne LiDAR survey, a funded by a NERC PhD studentship to Neil Dickson, a Royal Geographical Society Geographical Fieldwork Grant, and by the University of Leeds Academic Development Fund.
Proglacial landscape development in Iceland
(with Dr Andrew Russell, Newcastle University, UK)
Iceland has numerous glaciated and active volcanos. The proglacial areas receive annual pulses of meltwater and sediment with the Spring melt, glacier ice melt and some permafrost melt. However they are also subjected to the impacts of episodic high-magnitude outburst floods or 'jökulhlaups'. We are studying two key sites.
Eyafjallajökull is located in SW Iceland. It erupted in April 2010 and the resultant ash plume grounded aircraft across Europe. The eruption also caused rapid melting of a large volume of ice and this meltwater and volcanic sediment formed a slurry-type flow known as a 'lahar'. This is the first lahar observed in Iceland. We are looking at the flow character and impacts of this lahar as it routed along the Markarfljot valley to the south coast of Iceland.
This project is supported by a NERC PhD project studentship to Kate Satines and by a NERC Urgency grant.
Kverkfjöll is located on the northern margin of Vatnajökull ice cap, Iceland. It is an alpine mountain, is located in an active rifting zone, and is the southern part of the Kverkfjöll Volcanic System (KVS). A large glacier; Kverkjökull descends a vertical kilometre through a gap in the northern caldera rim. The northern part of the KVS is called Kverkfjallarani and comprises a series of parallel hyaloclastite and pillow lava ridges that were erupted into the last ice sheet. Kverkfjallarani is a semi-arid desert. This project aims to make a series of systematic and objective measurements and observations to characterise the detailed topography, geomorphology and sedimentology of different components of the KVS. This is in order to understand both contemporary and past processes that have shaped the landscape and produced distinctive landforms. In particular we are interested in the role of extremely large glacial outburst floods, or jökulhlaups, which have routed from Kverkfjöll, during the Holocene. Smaller jökulhlaups have originated from Kverkfjöll in historic times as well.
This project is supported by a NERC Airborne Research and Survey Facility (ARSF) award.
Proglacial lakes and jökulhlaups in west Greenland
(with Dr Andrew Russell, Dr Thomas Ingemann-Nielsen and Dr Jacob Yde)
A large glacial outburst flood or ‘jökulhlaup’ occurred in the Watson River, Kangerlussuaq, west Greenland on August 31st, 2007. The jökulhlaup was generated by the sudden drainage of an ice-dammed lake on the northern flank of the Russell Glacier, which is an outlet of the Greenland ice sheet.
This jökulhlaup occurred after the most intensive melt season ever witnessed on the Greenland ice sheet. Although there are many ice-dammed lakes at the margins of the Greenland ice sheet their drainage is rarely reported and their impacts remain unexamined.
The 2007 jökulhlaup is the first for 20 years from this location. We therefore hypothesise that this jökulhlaup will have high magnitude hydrological, geomorphological and sedimentological impacts. This is partly due to the length of time over which the system has been ‘re-stocked’ with sediment.
Our measurements of the flood impacts, and our reconstruction of the flood parameters and hydraulics, is important because arctic fluvial systems are expected to convey increasing volumes of meltwater runoff if current increases in ice-sheet surface ablation are sustained. Furthermore, proglacial fluvial systems of west Greenland provide a valuable modern analogue for former ice sheet margins, where prehistoric ice-dammed lake outbursts have delivered vast quantities of freshwater and sediment to the oceans, and have possibly contributed to temporary oceanic thermohaline disturbances.
