Fieldwork / Study
Geolocation is 75.63, -36
The aim of EastGRIP is to retrieve an ice core by drilling through the Northeast Greenland Ice Stream (NEGIS).
Ice streams are responsible for draining a significant fraction of the ice from the Greenland Ice Sheet, and we hope to gain new and fundamental information on ice stream dynamics from the project, thereby improving the understanding of how ice streams will contribute to future sea-level change. The drilled core will also provide a new record of past climatic conditions from the northeastern part of the Greenland Ice Sheet which will be analysed at numerous laboratories worldwide.
The EastGRIP project is both a logistic undertaking and a scientific collaboration. The logistics is coordinated by Physics of Climate, Earth and Ice (PICE, formerly Danish Centre for Ice and Climate) at the University of Copenhagen. The logistical tasks include making plans for field work, budgets, schedules, documentation for authorities, applying for permissions, purchasing equipment, planning flights, managing accounts, and hiring tradesmen and –women for field work.
The operations in Greenland require a close collaboration with the US Office of Polar Programs, National Science Foundation (NSF) and the NSF contractor in Greenland CH2MHill Polar Field Services. The flights take place in Hercules airplanes owned by the NSF and operated by the U.S. Air National Guard.
The aim of EastGRIP is to drill an ice core through more than 2550m of ice. The ice core can provide us with a range of information both on the dynamics of the ice (how the ice 'behaves') and on past climate (temperature, greenhouse gas concentration, vulcanic eruptions etc.).
Much of the fist field season (2016) was used to transform a freshly blown balloon trench into a working drilling trench with the aim to start deep drilling in earnest in 2017. Deep drilling with prototype borehole and surface control electronics with an intermediate length Hans Tausen drill was eventually achieved after many challenges throughout the 2017 season. A final depth of about 900 m was reached. In 2018 a final depth of 1750m was reached.
In addition to the deep drilling, a range of associated projects and measurements are conducted at the EastGRIP site. Below you can find descriptions of the EastGRIP associated projects for 2019.
Associated projects 2019
NEEM borehole logging (Dorthe Dahl-Jensen, NBI & Uni. Of Manitoba)
During the AWI North Greenland shallow drilling campaign, a team of three people will be flown to NEEM to perform a logging of the NEEM borehole. The operation is planned to last two days.
Surface movement by GPS (Christine Hvidberg, Aslak Grinsted, UCPH)
Surface velocity and strain rates will be measured by GPS in 2019 at EGRIP. The purpose is to provide 6 year long records 2015-2020 of surface movement at EGRIP and along NEGIS to validate satellite observations and reveal spatial and temporal variations of flow speed and elevation. In 2015, a strain net of 17 GPS poles were established at EGRIP and their 3D positions were measured (latitude, longitude, height). These poles were re-measured in 2017 and 2018 and will be measured again in 2019. See figure. A permanent GPS pole was established in 2015 at EGRIP. The station is planned as part of a survey along the NEGIS ice stream from the ice divide to the coast done in collaboration with DTU-Space, and the station will be monitored continuously. The station will be maintained and checked in 2019. More permanent poles were established in 2016, both upstream and downstream from EGRIP. Additional detailed surveys of surface movement are planned in 2019 in particular regions near EGRIP using surface GPS.
Map of the strain net at EGRIP showing the 17 poles established in 2015 (red crosses) and the two permanent GPS stations (blue circles). Only the permanent station close to the EGRIP camp as established in 2015. The EGRIP camp is indicated by the black cross. The background shows surface velocity derived from an optical IV method (Imgraft/Grinsted).
AWI North Greenland Traverse (NGT) shallow drilling (Basler) in NE Greenland (Maria Hörhold and Daniel Steinhage, AWI).
An extensive shallow drilling program is planned in NE Greenland with the aim of extending existing shallow core records of past AWI ice drilling traverses in NE Greenland up to present time. A few ice core from upstream of EGRIP are also planned. The operation is airborne, using the AWI Basler Polar 5. Polar 5 will be deployed at EGRIP from May 8 to May 30. In that time, the Basler will also fly three shuttles to Kangerlussuaq and support the borehole logging at NEEM.
EGRIP surface processes program (Main responsible: Hans Christian Steen-Larsen, University of Bergen and Maria Hoerhold, AWI )
Snow-air water vapor exchange
Purpose: To characterize and parameterize the water vapor isotopic exchange between the snow pack and the atmosphere in order to understand the post-depositional processes affecting the snowpack water isotopic composition
Measurements: Continuous water vapor isotope measurements at multiple levels Eddy-covariance measurements using multiple instruments PROMICE weather station including atmospheric temperature, wind, and humidity, snow surface temperature, snow pack temperature, snow height variations, incoming and outgoing radiation. Surface sampling along 100 m transect multiple times daily, for isotopic analysis. The top 100 cm will be sampled in high resolution every 2 weeks
Snow surface and snow pack properties
Purpose: To characterize and parameterize the post-depositional processes influencing the structure and spatial variability in the snow surface and snow pack properties
Measurements: Specific Surface Area of top 2.5 cm along a 100 m transect daily.
Accumulation and precipitation isotope studies
Purpose: To establish a dataset to be used for benchmarking of regional and general circulation model in the area around EGRIP
Measurements: Bamboo stake ‘forest’ will be measured 1-2 times every week to constrain accumulation and sublimation rates. Precipitation samples will be collected on tables lifted above the snow surface on event and sub-event resolution for sub-sequent isotopic analysis.
Ground based deep ice sounder (Prasad Gogineni, University of Alabama)
Four to seven people from the University of Alabama and AWI will test a new prototype ice deep sounder in the EGRIP area from mid July to the end of season in August. The radar assembly will be pulled by a Pistenbuly with transmit and receive antennas resting on inflated cushions (balloons). If testing is successful, the radar will be deployed for Dome C Antarctica shortly after EGRIP.
CryoEgg (Elizabeth Bagshaw, University of Cardiff).
The Cryoegg Project will develop a wireless system which uses radio frequency to measure the properties of deep ice and subglacial meltwater and return data to the surface. We are creating a ‘Cryoegg’, a small, wireless sensor that can measure the temperature, pressure and chemistry of the meltwater underneath the ice. The project is funded by the UK Engineering and Physical Sciences Research Council, and harnesses communications engineering methods to design a bespoke subglacial sensor for fast flowing ice. The Cryoegg must be able to collect fundamental measurements of water beneath up to 2.5 km of ice, be free to move within meltwater present beneath the ice, and transmit data to the surface. The sensor suite must be able to operate in low temperature, high pressure conditions, with no external power supply for up to 12 months. The radio data transmission must be efficient, able to pass through mixed media (ice, sediment, water, cracks), and received and recorded at the surface by a low power, small footprint receiver which can operate for prolonged timescales. Our tests at EGRIP will ensure the sensor is capable of operating in its target environment, and eventually collect data from beneath the ice stream. The project will enable the investigation of one of the last frontiers on planet Earth: subglacial environments, the cold, dark, high pressure zones beneath kilometres of ice.
Magnetotelluric Analysis for Greenland and Postglacial Isostatic Evolution (MAGPIE) (Clint Conrad, University of Oslo)
In the 2019 season, the MAGPIE project (Norway) will deploy up to 17 magnetotelluric (MT) instruments in a hub-and-spoke pattern around the EastGRIP station. These MT instruments will be located as much as 100 km away from EastGRIP, and will passively record fluctuations in electromagnetic fields for up to two weeks at a time. The MT data provide constraints on variations in the electrical conductivity beneath the station. Thus, they will help us to resolve any basal meltwater in the vicinity of EastGRIP, which is important for ice sheet dynamics. We also expect to detect variations in conductivity deeper beneath the ice sheet (100-300 km depth), possibly associated with variations in the temperature and water content of the upper mantle imparted by the Iceland plume. These water and temperature variations should also induce variations in upper mantle viscosity beneath Greenland. The new viscosity constraints for Greenland will be included within 3D models for ground deformation associated with deglaciation since the last ice age. By removing this ground deformation from modern geodetic observations, we can better constrain patterns and amplitudes of modern-day ice mass loss in Greenland. Due to possible logistical constraints, e.g. availability of snowmobiles, the program may be reduced from a full scale operation.
Surface Rover (Christine Hvidberg, NBI).
An autonomous GPS based vehicle for making automatic snow surface measurements is under development and will be tested at EGRIP by two people mid-July to beginning of August. Of special interest is testing whether a micro wind turbine will be a feasible source of energy.
Earthquake station at EGRIP (Trine Dahl‐Jensen and Tine B. Larsen, GEUS)
Starting in 2000, the seismological groups at KMS and GEUS – now all at GEUS – have placed earthquake seismic stations at over 20 sites in Greenland, both on the coast and on the ice sheet. We record globally occurring earthquakes, and use the data to investigate the local structure beneath and between the stations. A station was placed placed at EGRIP in a garage tent in 2015, and in 2016 the station was moved to the newly constructed core buffer trench. The station is solar/battery powered and collects data onto a memory chip. Once a year the memory chip is exchanged and the station is maintained.
PARCA AWS station system maintenance (Koni Steffen, ETH Zürich, CIRES Colorado)
During the annual maintenance of the Automated Weather Stations in N-Greenland, the EGRIP camp will be re-fuelling station and base for the PARCA team for several days in May. PARCA uses a Twin Otter air craft.
GLISN seismic network. (The GLISN project)
The GLISN network operates several permanent seismic stations on the Greenland ice sheet, e.g. at Summit and at the NEEM site. Normally, during the annual maintenance of the sites, the team uses EGRIP as a re-fuelling and over-night stop. However, in 2019 no maintenance is planned except for the maintenance provided by the borehole logging team at NEEM.
Bagshaw E, Karlsson N, Lok L, Lishman B, Clare L, Nicholls K, Burrow S, Wadham J, Eisen O, Corr H, Brennan P, Dahl-Jensen D
Prototype wireless sensors for monitoring subsurface processes in snow and firn.
Journal of Glaciology, 1-10, 2018
Look up abstract/reprint using doi:10.1017/jog.2018.76
Hoffman OA, Steen-Larsen HC, Christianson K, Hvidberg C
A low-cost autonomous rover for polar science.
Geoscientific Instrumentation, Methods and Data Systems Discussions, 2019
Look up abstract/reprint using doi: 1-18. 10.5194/gi-2018-52
Madsen MV, Steen-Larsen HC, Hörhold M, Box J, Berben S, Capron E, Faber AK, Hubbard A, Jensen M, Jones T, Kipfstuhl S, Koldtoft I, Pillar H, Vaughn B, Vladimirova D, Dahl-Jensen D
Evidence of isotopic fractionation during vapor exchange between the atmosphere and the snow surface in Greenland
Journal of Geophysical Research: Atmospheres, 2019
Look up abstract/reprint using doi: 10.1029/2018JD029619