Surface Processes of the Greenland Ice Sheet Under a Warming Climate

PI Institute/Department Email
Steffen, Konrad
U of Colorado, Boulder, Cooperative Institute for Research in Environmental Sciences
Award#(s)
NASAAWS
Funding Agency
US\Federal\NASA
Program Manager Funding Agency Email
Wagner, Dr. Thomas
NASA
Discipline(s)
Cryosphere
Meteorology and Climate
Science Summary

A part of the NASA-sponsored PARCA (Program in Arctic Regional Climate Assessment) project, researchers on this NSF co-funded project have installed and are currently maintaining 18 Automatic Weather Stations (AWS). Each AWS is equipped with a number of instruments to sample the following: -air temperature, wind speed, wind direction, humidity, pressure -accumulation rate at high temporal resolution to identify and resolve individual storms -surface radiation balance in visible and infrared wavelengths -sensible and latent heat fluxes -snowpack conductive heat fluxes Hourly average data are transmitted via a satellite link (GOES or ARGOS) throughout the year. In addition, measurements are stored in solid state memory. The system is powered with two 100 Ah batteries, charged by a 10 or 20 W solar panel. The satellite data-link is powered by two separate 100 Ah batteries connected to a 20 W solar panel. This setup guarantees continuous data recordings and storage, even in the case of satellite transmission failure. The expected lifetime of the instrumentation is 5 years. PARCA GC-Net Automatic Weather Stations (AWS) are equipped with communication satellite transmitters that enable near-real time monitoring of weather conditions on the Greenland ice sheet. Transmission latency is as short as 4 minutes, typically 1-2 hours, and occasionally as long as 48 hours.

Logistics Summary

This project is co-funded between NSF and NASA. In 1995, the PI initiated a network of Automatic Weather Stations (AWS) on the Greenland ice cap. Each year since then, a team of four to five travels to the project's sites via Twin Otter for maintenance, repairs, and upgrades. Additionally, the team tent-camps at Swiss Camp for several weeks to conduct more intensive measurements related to the state of the ice sheet. These include monitoring ablation in the Jakobshavn region (in collaboration with Dr. Jay Zwally [NASA-GSFC]); and measuring accumulation variability, mass transfer, and surface energy balance. In 2007, one person will visit Summit Station to install a thermistor string to capture hourly temperature profiles in the upper ~100 m of ice. The researcher will use an empty borehole. The data will help the team reconstruct surface temperature history on a multi-decadal to century scale. The researcher will spend about a week at Summit setting up the experiment, which may remain in place for several years. Also in 2007, the PI’s graduate student will base from Ilulissat and fly a NOAA-funded UAV experiment in early May and again in July to collect high-resolution laser data around Swiss Camp during the pre-melt and melt season. These data will help researchers calculate surface water storage on the ice sheet. New at Swiss Camp in 2008, a UAV equipped with laser instruments to collect high-resolution data about surface water storage.This NOAA-funded project uses a UAV based in Ilulissat to collect high-resolution laser data around Swiss Camp during the pre-melt and melt season. These data are used to calculate surface water storage on the ice sheet. The information contributes to the PI’s sub-glacier hydrological modeling study (“GPS Network Maintenance,” above). The PI’s graduate student, John Adler, will fly the UAV in early May and again in July to collect the data in the second and final field season for this project. In 2009, mid-April to mid-May, the researchers will maintain the automatic weather station network. In the south, they will service the Dye-II, Saddle, NASA SE and S-Dome stations, and during the Swiss Camp put in the CP1 and NASA-U stations. While at Swiss Camp, the team will service the profile JAR2, JAR1, and CU/ETH. They will continue the effort to monitor ablation along a transect from Swiss Camp to the ice margin. The Swiss Camp team will service eight receivers in the GPS network in collaboration with Dr. Jay Zwally (NASA-GSFC). They will continue to collect high-resolution surface topography data using Trimble Pathfinder differential GPS measurements along several transects in the lower ablation region. In addition, they will acquire a set of QuickBird satellite imagery during the onset of melt and the melt period to monitor the spatial variation and extent of snow fields, lakes, and surface hydrological channels in the ablation region. This project has collected a number of ground penetrating radar (GPR) profiles along the western slope of the ice sheet (Jakobshavn and Kangerlussuaq region) in previous field seasons (1999, 2000, 2003). Data analysis showed that the accumulation could vary up to 40% between the trough and the ridge of the undulation. (Surface topography with scale length of several kilometers plays an important role for the spatial variability of accumulation, mass transfer, and surface energy balance.) The team repeated some of these GPR measurements during the spring 2007 field season along the same profiles to verify the recent accumulation changes and high percolation events in that region. In addition to science research, the PI will host two media visits in spring 2009: (a) MISCHIEF FILMS, Austrian documentary film about Albert Schweitzer. The crew will participate for one day and one night during the southern AWS maintenance trip. (b) National Geographic, documentary called “The Big Picture.” The crew visits Swiss Camp May 3-5. They will organize their own helicopter flight from Ilulissat to Swiss Camp and back. In 2010, DRI's Joe McConnell and an ICDS driller will join the AWS maintenance visits to Humboldt and TUNU to drill shallow cores for analysis related to the NEEM deep drilling project (0909541). Participant travel for McConnell and the driller to Kangerlussuaq will be carried under his NSF grant record. In 2011, a team of about eight will arrive in Greenland around 1 May. They will first travel via Twin Otter to Swiss Camp to install new extension poles on the GPS network; and to maintain/upgrade (with new satellite transmitters) the AWS network stations JAR2, JAR1, Swiss Camp, and Crawford Point. Around Swiss Camp and in the lower ablation region the team will map sub-glacial melt channels using a new MALA ground penetrating radar with a 20 MHz antenna. They also will install new seismic stations close to Swiss Camp and in the lower ablation region close to a moulin. Researchers for NSF grant 0909454, Ginny Catania, PI, also will visit Swiss Camp at the same time to work on the project’s GPS experiment. Researchers also will visit AWS stations in the north of Greenland (NEEM, GITS, Petermann, Tunu-N, Humbold, NASA-U, and NASA-E) and in the south (Dye-II, Saddle, NASA-SE, and Saddle) for maintenance service. At Summit researchers will maintain the 50m Swiss Tower and the Baseline Surface Radiation Network (BSRN); these provide the basing meteorological and radiation data for other Summit researchers. In 2013, a team of four will fly commercially to Kanger for a Twin Otter put-in to Swiss Camp in early May for a three-week effort at the camp. Three more researchers will arrive mid-May on a helicopter flight arranged and paid for by the PI’s institution (CU). The three new arrivals plus one original team member will depart a few days later on another CU-chartered helicopter flight. The Twin Otter will return to Swiss camp in late May to pick up the remaining team members and begin transporting them to the southern set of AWS stations (Dye-II, NASA-SE, and Saddle), with air support based from Kangerlussuaq. A team of four will then depart Kangerlussuaq via Twin Otter to begin visiting the northern AWS sites (NEEM, GITS, Petermann, Tunu-N, Humbold, NASA-U, and NASA-E), working out of Daneborg, Qaanaaq, and NEEM. The team will wrap up Twin Otter work with a visit to Summit Station, overnighting to service the Swiss Tower and the Baseline Surface Radiation Network (BSRN), which provide the basing meteorological and radiation data for other Summit researchers. In mid-August, a team will return to Swiss Camp and the Moulin Site via helicopter out of Ilulissat to make late-season repairs to the camp, which sustained considerable damage during the 2012 melt season. After about one week at camp, the team will depart via helicopter and commercial air. In 2014, a team of six will fly commercially to Kangerlussuaq for a Twin Otter put-in to Swiss Camp in early May. The team will spend ~two weeks based at the camp. The Twin Otter will return to Swiss camp in mid-May to pick up the team and begin transporting them to the southern set of AWS stations (Dye-II, Saddle, NASA-SE, and Saddle), with air support based from Kangerlussuaq. A team of four will then depart Kangerlussuaq via Twin Otter to begin visiting the northern AWS sites (NEEM, GITS, Petermann, Tunu-N, Humboldt, NASA-U, and NASA-E), working out of Daneborg, Qaanaaq, and NEEM. The team will wrap up Twin Otter work with a visit to Summit Station, overnighting to service the Swiss Tower and the Baseline Surface Radiation Network (BSRN) which provide the basing meteorological and radiation data for other Summit researchers. In 2015, a team of six will fly commercially to Kangerlussuaq for a Twin Otter put-in to Swiss Camp in early May. The team will spend ~two weeks based at the camp. The Twin Otter will return to Swiss camp in mid-May to pick up the team and begin transporting them to the southern set of AWS stations

CPS will provide ANG cargo coordination from the U.S., chartered air support within Greenland, lodging and user days, camping gear, fuel, and safety and communications equipment. Costs will be covered in the following ways: NASA will pay 100% of Swiss Camp support costs. NSF and NASA will each pay for 50% of the remaining activities. NSF will recoup costs from NASA via an interagency funds transfer NASA > NSF. The PI will arrange and pay for other work directly.

Season Field Site Date In Date Out #People
1996
Greenland - Summit
1
1997
Greenland - Summit
1
1998
Greenland - Summit
1
1999
Greenland - Summit
1
2000
Greenland - Summit
4
2001
Greenland - Summit
4
2002
Greenland - Summit
2
2003
Greenland - Summit
1
2005
Greenland - Summit
3
2007
Greenland - Summit
1
2008
Greenland - Summit
5
2011
Greenland - Summit
0
2012
Greenland - Summit
4
2014
Greenland - Summit
4
2015
Greenland - Summit
5
2016
Greenland - Summit
5
2017
Greenland - Summit
4
2018
Greenland - Summit
1