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2006 ANNUAl repOrt

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� �006 UNAVCO Arctic Sciences Annual Report

GNSS Support to the National Science FoundationOffice of Polar Programs

Arctic Sciences

2006 Annual ReportDecember 1, �006

Bjorn Johns

UNAVCO, Inc.

6350 Nautilus Dr.

Boulder, CO 80301

www.unavco.org

Support funded by the National Science Foundation Office of Polar ProgramsSupplement to EAR-03�1760 - Support of UNAVCO Community and Facility Activities

Cover photo: High-Arctic desert near Thule, Greenland.

3 �006 UNAVCO Arctic Sciences Annual Report

Table of Contents

Summary �� 4

Table 1 – 2006 Support Provided .......................................................................................................................................................... 6

Science Support �� 7

Training ................................................................................................................................................................................................. 7Field Support ......................................................................................................................................................................................... 7Data Processing .................................................................................................................................................................................... 7Data Archiving ....................................................................................................................................................................................... 7

Equipment �� 8

Science Pool ......................................................................................................................................................................................... 8Table � – Equipment Deployed Long Term at Remote Facilities .......................................................................................................... 9Atqasuk GPS Base Station ................................................................................................................................................................... 9Barrow Differential GPS System ......................................................................................................................................................... 10Summit GPS Base System ..................................................................................................................................................................11Toolik Field Station Differential GPS System ...................................................................................................................................... 13

Future Plans �� 14

Appendix A - Detailed Summary of Support Provided �� 15

Arctic Tundra Thermocarst (Ted Schurr – University of Florida Gainesville)....................................................................................... 15Atqasuk GPS Base (Bjorn Johns – UNAVCO) .................................................................................................................................... 15Barrow BAID-IMS (Pat Webber – Michigan State University .............................................................................................................. 15Barrow Biocomplexity (Walter Ochel – San Diego State University) .................................................................................................. 15Barrow GPS Base (Glenn Sheehan – Barrow Arctic Science Consortium) ........................................................................................ 15Bench Glacier (John Bradford - Boise State University) ..................................................................................................................... 15Beringia (Craig Tweedie – University of Texas El Paso) ..................................................................................................................... 15Circumpolar Active Layer Monitoring Network - CALM (Frederick Nelson – University of Delaware) ................................................ 16Greenland Helheim Glacier (Jim Davis - Harvard Smithsonian) ........................................................................................................ 16Greenland Jakobshavn/Kangia Base Station (Bjorn Johns – UNAVCO) ............................................................................................ 16Greenland Peripheral Thinning (Tom Neumann – University of Vermont) .......................................................................................... 17Greenland Petermann Gletscher (Konrad Steffen – University of Colorado) ..................................................................................... 17Greenland Summit GPS Base (Bjorn Johns - UNAVCO).................................................................................................................... 17Greenland Supraglacial Lakes (Sarah Das – Woods Hole Oceanographic Institute) ......................................................................... 17Greenland Thule/Green Valley (Jeff Welker – University of Alaska Anchorage) ................................................................................. 18Himalaya Ground Control Point (Adina Racoviteanu – University of Colorado) ................................................................................. 18Iceland Breidamerkurjokull (Slawek Tulaczyk – University of California Santa Cruz) ......................................................................... 19Kennicott Glacier (Robert Anderson – University of Colorado) ........................................................................................................... 19McCall Glacier (Matt Nolan – University of Alaska, Fairbanks) ........................................................................................................... 19North Cascades (Erin Pettit – University of Washington) .................................................................................................................... 19St. Elias Erosion/Tectonics Project (STEEP) (Jeff Freymueller – University of Alaska, Fairbanks) .................................................... �0Toolik Field Station Differential GPS System ...................................................................................................................................... �0

Appendix B – Staff Time Breakdown �� 21

Table 3 – Estimate of Staff Weeks per Project and Task .................................................................................................................... �1

� �006 UNAVCO Arctic Sciences Annual Report

UNAVCO is the National Science Foundation’s and NASA’s pre-eminent national facility for Earth science applications of Global Navigation Satellite Systems (GNSS1) including the Global Positioning System (GPS). The range of services provided to the National Science Foundation’s Office of Polar Programs (NSF-OPP/ARC) Arctic Sciences Section includes equipment, training, project planning, field support, proposal assistance, technical consultation, data processing, and data archiving on a year-round basis. Permanent station network support services are also provided, from the initial engineering and installations through operations, maintenance, and data archival and distribution. Sustaining engineering activities are ongoing to meet the technical challenges such as providing robust telemetry and power systems at remote high-latitude locations. Resources and expertise from the other core UNAVCO support areas, including NSF-EAR investigator support, NASA-Global GNSS Network (GGN) operations, the EarthScope/Plate Boundary Observatory facility construction and operation, and the UNAVCO community data archive are leveraged to apply state-of-the-art technologies at a reasonable cost.

A substantial increase in remote permanent station and network support activities in polar regions was developed during 2006. While this effort is primarily targeted at Antarctic research needs, it has direct applications for Arctic research. UNAVCO now offers a centralized source for polar permanent station equipment and the associated technical expertise for successful deployment and robust data collection, including attention to long-term operation and maintenance issues. System configurations and data management meet best practices and global standards that are often set by the UNAVCO community. However, significant technical challenges also remain to enable year-round operation of and data retrieval from remote polar autonomous systems envisioned for future geophysical research initiatives. Meeting these challenges requires a focused engineering effort, and UNAVCO, together with the Incorporated Research Institutions for Seismology (IRIS), recently received a Major Research Infrastructure (MRI) award to design and build the next generation power and communication system for autonomous polar station operation.

Seventeen Principal Investigator based Arctic projects encompassing a range of applications were supported during 2006 (Figures 1 and �). Four infrastructure and operational projects were also supported, including establishing a new base station and field survey system for Summit Camp, Greenland, a base station near Ilulissat, Greenland, a base station in Atqasuk, Alaska, and hardware upgrades and training in Barrow, Alaska. Table 1 summarizes projects supported, and Appendix A provides more detailed descriptions of the individual projects. Appendix B provides a staff-time breakdown of the major tasks supported. The UNAVCO Facility web site (facility.unavco.org) provides comprehensive and historical information related to Polar Programs support.

1. GNSS refers to all modern satellite navigation systems, including GPS, the Russian GLONASS, and the emerging European Galileo systems. While UNAVCO’s support continues to be based on GPS, new hardware is beginning to incorporate the reception of other signals and we expect this trend to continue as new products emerge on the market.

Summary


Figure 1 – Western U.S. research project locations.

Figure � – Greenland and Iceland research project locations.


Project Funding Source Point of Contact Eqp� Loan Qty. Field

Support Training Data Archived

Data processed

Arctic Tundra Thermocarst ARC-05163�6 Ted

Schurr X � X

Atqasuk GPS Base OPP Bjorn Johns X 1 X X

Barrow BAID-IMS OPP-0454996 Craig Tweedie X 1 X

Barrow Biocomplexity OPP-0421588 Craig Tweedie X 1 X

Barrow GPS Base OPP Glenn Sheehan X 3 X X X X

Bench Glacier ARC-0�5�717 John Bradford X 5 X

Beringia OPP-0454997 Craig Tweedie X � X

Circumpolar Active Layer Monitoring OPP-0352958 Frederick

Nelson X � X

Greenland Helheim Glacier PI internal Jim

Davis X �0

Greenland Jakobshavn Base Station NASA/OPP Bjorn

Johns X 0 X

Greenland Peripheral Thinning

NASA NNG-06GA83G

Tom Neumann X 10

Greenland Petermann Gletscher OPP-0135450 Konrad

Steffen X 1

Greenland Summit GPS Base OPP Bjorn

Johns X � X X X X

Greenland Supraglacial Lakes ARC-05�0077 Ian

Joughin X 5 X

Greenland Thule/Green Valley OPP-0221606 Ron

Sletten X � X X X X

Himalaya Ground Control

NASA 06-ESS06 -137

Adina Racoviteanu X � X

Iceland Breidamerkurjokull OPP-0136112 Slawek

Tulaczyk X 0

Kennicott Glacier EAR-05�9566 Robert Anderson X 6 X

McCall Glacier OPP-0229705 Matt Nolan X 5 X X X X

North Cascades Glacier Monitoring Pilot project Erin

Pettit X 3

STEEP EAR-0�09��6 Jeff Freymueller X 8 X

Table 1: 2006 Arctic Projects Receiving UNAVCO Support


The UNAVCO Facility provides state-of-the-art GPS project management, equipment and field engineering support for prin-cipal investigator projects and for installing, operating and maintaining continuous GPS networks world-wide. UNAVCO also undertakes new technology development and evaluation of commercially available products for research applications, and archives GPS data and data products for future applications. The following highlights some of the resources and capabilities available for science project support:

• Expertise in program and project management, field engineering, technical support, and training

• Equipment and laboratory facilities for maintaining repairing, testing, and deploying equipment

• Systems integration and software development capabilities for custom applications

• Formal systems for property management, import/export, shipping and logistics; grant administration, project financial management, tracking, and reporting; established processes and procedures for supporting scientific research

These capabilities are drawn upon to provide support tailored to the needs of Arctic research projects as summarized be-low.

TrainingFlexible options for field team training include training before deployment to the field, training in the field, and direct field engineering support during the project. The level of training is tailored to the experience of each research group. Training was provided both in Boulder and in the field for Summit Camp staff to familiarize them with the new GPS survey system, and refresher training was provided in Barrow for several users of the GPS system at the Barrow Arctic Science Consortium (BASC). Project specific training was also provided for seven other science projects as noted in Table 1.

Field Support

Field support is provided to groups that desire technical support for their geodetic GPS surveys. Direct field support was provided for the Atqasuk base station installation, Summit Camp GPS system installation, Barrow GPS system maintenance, and for the McCall Glacier and Thule/Green Valley field projects. Remote technical support is also provided via telephone, email, and documentation on the web.

Data Processing

Post-processing of differential GPS data is required to achieve millimeter to centimeter level precision. UNAVCO supports data processing in the field using Trimble Geomatics Office (TGO) software. Post-season data processing support is also provided, using TGO software and the Canadian Spatial Reference System on-line data processing service, and the EarthScope/Plate Boundary Observatory data analysis system may be used to generate daily positions and position timeseries for permanent station data collected on the North American tectonic plate. Precipitable water vapor data can also be determined from GPS permanent station data using the University Corporation for Atmospheric Research (UCAR) COSMIC program’s GPS-met analysis capabilities. This season data processing support was provided for the McCall Glacier and Thule/Green Valley projects. In addition, GPS-met data and a continuous position time series are produced for the Summit Camp base station, and a position time series is produced for the EarthScope GPS station in Barrow.

Data Archiving

All GPS data handled by UNAVCO are archived at the Boulder archive to ensure data safeguarding and future accessibility. The data are organized by project name and year in an open access, searchable on-line database. Archiving services are available to all NSF sponsored geodetic GPS projects, not just those directly supported by UNAVCO, and all investigators are encouraged to archive their data immediately after project completion.

Science Support


Equipment

Science PoolGPS equipment is available for geodetic surveying, mapping, and permanent station applications. Eight new Trimble R7 geodetic survey receivers were purchased, for a total of thirty-one NSF-OPP Arctic Sciences receivers in the UNAVCO pool. Four of these receivers were purchased using supplemental funding provided by the NASA Oceans and Ice program for support to the Greenland Peripheral Thinning project. Eight receivers are deployed long-term at Atqasuk, Barrow, Summit Camp, and Toolik Field Station (Table �). Forty-six additional receivers from the UNAVCO pool were provided for project support throughout the field season to meet high-precision GPS demands from the Arctic research community (Figures 3 and �). Ancillary equipment such as data processing software, solar panels, batteries, chargers, tribrachs, tripods, and cables is also provided.

Figure 3 (left) - Support to Arctic research projects has grown steadily during the first five years of UNAVCO’s general support to the NSF Arctic Science program.

Figure � (right) - Demand for receivers will likely continue to increase with more research projects deploying larger number of receivers for ice dynamics measurements on the Greenland ice sheet and Arctic glaciers, and new receiver acquisition continues in response to this trend.

Complete integrated enclosure and solar power system “glacier boxes” were developed to support the Greenland Supraglacial Lakes project (Figure 5). These systems were designed for long term (months to years) glaciological applications in mind such as ice shelf, ice sheet, and glacier data collection. They are also suited for solid Earth applications in remote environments. The case is the Mil-Spec Hardigg “Mobile Master 36” and holds six 100Ah sealed lead acid batteries under the instrument board. Rugged external connectors on the box simply field set-up. The boxes can be adapted to also include seismic equipment. UNAVCO coordinated with IRIS to make the systems compatible with the seismic systems that IRIS provided to the Greenland Supraglacial Lakes project, eliminating the need to duplicate similar power/enclosure systems for GPS and seismic instrumentation (Figure 6). Based on the successful deployment and positive feedback from the science team, UNAVCO intends to add more boxes to the pool inventory for future project applications. To support such efforts, 500 square feet of shop space was recently acquired and is devoted exclusively to design, fabrication, testing, and storage of GPS systems for use in the polar regions. This workspace includes a complete stock of tools and hardware, and represents a significant increase in capability to meet the growing needs of the scientific community for robust, rapidly deployable, year-round GNSS systems.

Annual Projects Supported 2002-2006

6

11 11

14

20

0

5

10

15

20

25

2002 2003 2004 2005 2006

Arctic Project Receiver Use 2002-2006

5 610

2331

12

20 12

15

46

0

10

20

30

40

50

60

70

80

90

100

2002 2003 2004 2005 2006

Additional receivers provided from NSF-ANT and NSF-EAR programs.

NSF-ARC receivers


Figure 5 (left) – Easy to deploy glacier box with external connectors for solar power, GPS antennas and seismic sensor.

Figure 6 (right) – Box interior layout design accommodates both UNAVCO GPS and IRIS seismic equipment.

Table 2 – Equipment Deployed Long Term at Remote Facilities

Location GPS receivers Radio modems Other equipment (value > $1000)

Atqasuk ARM Facility 1 TNL NetRS

Barrow Arctic Science Consortium

1 TNL NetRS 1 TNL 5700 1 TNL R7

1 TNL HB�50 2 PC RFM96-2W

1 TSC1 survey controller 1 TSC� survey controller

Summit Camp 1 TNL NetRS 1 TNL R7

1 TNL HB�50 1 TSC� survey controller 1 Vaisala WXT510 metpack

Toolik Field Station 1 TNL NetRS 1 TNL 5700

1 TSCe survey controller

Atqasuk GPS Base Station A GPS receiver and antenna were installed in Atqasuk, Alaska, located approximately 70 miles south of Barrow. This base station (ATQK) provides a local source of geodetic quality differential corrections for GPS data post-processing of surveys in the Atqasuk area on the Alaska North Slope. The station is located at the Atmospheric Radiation Measurement (ARM) Climate Research Facility (ACRF) which provides security, power, and Ethernet communications. The antenna is mounted on the mezzanine railing of the ACRF facility, which sits on a gravel pad on unconsolidated earth (Figure 7). The Trimble NetRS receiver is operated remotely by UNAVCO specifically for users who have requested base GPS data in Atqasuk similar to that provided by UNAVCO and the Barrow Arctic Science Consortium in Barrow. The station runs continuously, and 15 second sample rate data are archived at UNAVCO (facilty.unavco.org) and available to the public. Higher sample rate data are also recorded on the receiver in hourly files, and are made available to users as needed. System details for users are provided on-line. All data are available via the Internet, and there is no need for users to have physical access to the receiver. The site could be upgraded to provide GPS meteorological data in the future, as well as RTK corrections if there is demand for such upgrades.


This season, the station was used by the Global Change Research Group and San Diego State University to provide high frequency base station data for post processed DGPS corrections for a small aircraft. and by researchers Beck, Eisner and Nelson. These and other researchers have expressed interest in such a base station during the past several years, and a handful of projects will likely use the station data every year.

Figure 7 (left) – The new Atqasuk GPS base is hosted at the ARM Climate Research Facility and serves researchers in the Atqasuk vicinity.

Figure 8 (right) - A University of Texas, El Paso (UTEP) research team member is trained to use the new Trimble R7 receiver and TSC2 controller which were added to the Barrow GPS system in June.

Barrow Differential GPS System

Two Trimble real-time kinematic (RTK) differential GPS (DGPS) rover systems are available for dedicated use at the Barrow Arctic Science Consortium (BASC) to meet the surveying needs of researchers working at BASC. UNAVCO provides year-round technical support to users of this system and maintains a web page with the relevant system technical information, while BASC provides the day to day operational support including equipment scheduling and issue. To ensure the continued success of the Barrow system to local science users, UNAVCO staff makes annual maintenance/training visits, usually in conjunction with related project requests. This year, two visits were made to strengthen BASC-UNAVCO ties regarding GPS system support, and Bob Bulger of BASC visited UNAVCO in March. In April Bjorn Johns and Susan Eriksson, UNAVCO’s Education and Outreach (E&O) Director, visited BASC to explore the potential for collaboration on future E&O opportunities, develop a management plan for the equipment with a more active BASC role, review the equipment maintenance plan, review the need for updated system documentation, and provide refresher training to BASC personnel. Field engineer Thomas Nylen visited Barrow in early June. During this visit the base radio was upgraded to a Pacific Crest HPB450, and a new Trimble R7 rover receiver with an internal radio and TSC� controller were added to the list of available equipment for users at the BASC facility. On-site training was also provided to University of Texas El Paso undergraduate research assistant Adrian Aguirre tasked to manage the equipment during the summer (Figure 8).


Summit GPS Base System

A permanent GPS base station (Figure 9) and rover system were installed at Summit Camp with real-time kinematic (RTK) surveying capability. The system consists of a continuously operating base receiver and a roving receiver with ancillary equipment. UNAVCO is available for year-round technical support to users of this system and maintains a web page with the relevant system technical information, In addition to providing precision mapping and topographic surveying capability, the system will also allow measurement of ice motion and yield data for atmospheric studies. While on-site, UNAVCO engineers Seth White and Thomas Nylen also performed two short surveys to update the position of the aircraft skiway and measure snow accumulation along a previously surveyed transect. A GPS monument was also installed on the GISP2 borehole casing (Figure 10) to provide a reference point which is fixed to the underlying ice. GPS data from the site and a position time series are available on-line from UNAVCO. Pressure, temperature, humidity, and column water vapor data derived from GPS are available on-line from UCAR (www.suominet.ucar.edu, Figure 11). Groups and field teams that used the system this season include Albert, Anandakrishnan, Bales, Bergin, Hawley, Jet Propulsion Laboratory, Steig, and Veco Polar Resources.

Figure 9 (left) – Base station SUMM geodetic antenna mounted on the Green House roof.

Figure 10 (right) – A GPS monument on the GISP 2 borehole casing provides a reference point fixed to the underlying ice to correct for the inevitable settling of the Green House as the underlying snow and firn compact.

1� �006 UNAVCO Arctic Sciences Annual Report

Figure 11 – Meteorological data including GPS derived column water vapor from station SUMM are available on-line and archived by UCAR.


Toolik Field Station Differential GPS System

A Trimble 5700 real-time kinematic (RTK) differential GPS (DGPS) system is available for dedicated use at the Toolik Field Station to meet the surveying needs of researchers working in the vicinity of Toolik Lake on the north side of Alaska’s Brooks Range. The real-time capability increases the system versatility in proximity of the station (for example it allows for stakeouts of pre-determined points), while the post-processing capability using Trimble Geomatics Office software extends the system radius to over 100km from the station. No major support was requested from UNAVCO this year due to the skilled and experienced GIS/GPS staff at Toolik Field Station, Lael Rogan and Andrew Balser.

1� �006 UNAVCO Arctic Sciences Annual Report

Future Plans

The following activities are planned to improve data acquisition, network support, and data analysis:

1. Continue Iridium data retrieval development efforts. Iridium/GPS integration efforts to date have been successful in providing a robust system to download full GPS data from the most remote locations. However, there are still challenges that UNAVCO will continue to pursue, including reducing the system power requirements and applying the short burst data (SBD) mode for improved efficiency.

2. Pursue development activities as outline in the Major Research Infrastrucutre (MRI) development proposal Collaborative Research: Development of a Power and Communication System for Remote Autonomous GPS and Seismic Stations in Antarctica. The technology development resulting from this proposal effort will benefit future remote Arctic GPS installations.

3. Support the creation of a UNAVCO Polar Networks Science Committee. A polar–focused advisory committee has been established and includes members of the polar GPS and seismic communities. This committee allows for the direct participation of the polar science community in UNAVCO as a consortium that provides them with considerable resources. Such a committee is seen to be necessary should a large polar GPS network initiative come to fruition, and it was included in the management plan of the MRI proposal. The committee could also coordinate input from the science/research community regarding polar networks and science requirements, advise and engage on polar GPS and proposal initiatives, and assist with the development of acquisition proposals for polar remote station components and systems.

�. Explore long-term solutions for advanced data processing support. The commercial data processing software supported by UNAVCO works well for new users and smaller projects. However, several projects could benefit from using more rigorous and adaptable academic data processing software. Proficiency in such software requires regular use, and UNAVCO is well positioned to work with the science community to develop a solution that relies upon community expertise to reduce barriers to entry for new users. A possible solution would be the establishment of a community processing center, where new users can work through their data with expert assistance present.

5. Monitor terrestrial laser scanning (TLS) technology for Arctic applications. UNAVCO, together with the emerging LIDAR community, have submitted a proposal for the acquisition of tripod based LIDAR units for PI community and EarthScope applications. Such units have the potential to augment GPS surveys for applications such as high precision surface mapping and stability monitoring. As UNAVCO gains experience with this emerging technology, its suitability for Arctic applications will be evaluated.


Appendix A - Detailed Summary of Support Provided

Arctic Tundra Thermocarst (Ted Schurr – University of Florida Gainesville)) Two receivers and training were provided to accurately measure microtopographical changes that have occurred as

permafrost has thawed and thermokarst has developed. This project studies the carbon balance of Arctic tundra in re-sponse to permafrost thawing, using radiocarbon to detect the loss of old carbon.

Atqasuk GPS Base (Bjorn Johns – UNAVCO) A Trimble NetRS base station receiver and antenna were installed at the Atmospheric Radiation Measurement (ARM)

Climate Research Facility (ACRF) in Atqasuk, Alaska, approximately 70 miles south of Barrow. The GPS base station (ATQK) provides a local source of geodetic quality differential corrections for GPS data post-processing by scientists and others operating in the Atqasuk area. The station runs continuously, and 15 second sample rate data are archived at UNAVCO (facilty.unavco.org) and available to the public. The Ethernet enabled receiver is operated remotely by UNAVCO specifically for users who have requested base GPS data in Atqasuk similar to that provided by UNAVCO and BASC in Barrow. See the Equipment diction of this report for more information regarding the Atqasuk GPS base.

Barrow BAID-IMS (Pat Webber – Michigan State University) A dedicated rover RTK receiver system and training were provided to locate and document the location of extant and

historical research sites within the area of interest of the Barrow Area Information Database and Internet Map Server (BAID-IMS).

Barrow Biocomplexity (Walter Ochel – San Diego State University) Training and a dedicated rover receiver system were provided. This project examines how biological and physical processes

interact to control carbon uptake, storage and release in Arctic tundra ecosystems and how the self-organizing nature of these interactions varies across multiple spatial and temporal scales. A semi-permanent RTK repeater, set up at the tramway computer building, provides differential corrections from the Barrow base.

Barrow GPS Base (Glenn Sheehan – Barrow Arctic Science Consortium) Two Trimble real-time kinematic (RTK) differential GPS (DGPS) rover systems are available for dedicated use at the

Barrow Arctic Science Consortium (BASC) to meet the surveying needs of researchers working at BASC. To ensure the continued success of the Barrow system to local science users, UNAVCO schedules an annual maintenance/training visit, usually in conjunction with related project requests. This year, two visits were made to strengthen BASC-UNAVCO ties regarding GPS system support, and Bob Bulger of BASC visited UNAVCO in March. In April Bjorn Johns and Susan Eriksson, UNAVCO’s Education and Outreach (E&O) Director, visited BASC to explore the potential for collaboration on future E&O opportunities, develop a management plan for the equipment with a more active BASC role, review the equipment maintenance plan, review the need for updated system documentation, and provide refresher training to BASC personnel. Field engineer Thomas Nylen visited Barrow in early June. During this visit the base radio was upgraded to a Pacific Crest HPB450, and a new Trimble R7 rover receiver with an internal radio and TSC2 controller were added to the list of available equipment for users at the BASC facility. On-site training was also provided to University of Texas El Paso undergraduate research assistant Adrian Aguirre tasked to manage the equipment during the summer. See the Equipment diction of this report for more information regarding the Barrow GPS system.

Bench Glacier (John Bradford - Boise State University) This project is studying water storage and routing within glaciers, and a new model of glacier hydrology. Five receivers

were provided for kinematic GPS control for GPR surveys and for geodetic precision measurements of glacier motion. Training and consultation were also provided prior to the field project.

Beringia (Craig Tweedie – University of Texas El Paso)

Two receivers and training were provided to conduct static and kinematic field surveys at multiple sites in the Beringian Arctic including remote sites in Russia and Alaska. The project objective is to determine the impact of decadal time scale land cover change on plot to landscape-level carbon flux at multiple sites throughout the Beringia region.


Circumpolar Active Layer Monitoring Network - CALM (Frederick Nelson – University of Delaware) UNAVCO provided two GPS receivers and data processing software. This was the sixth season this project used GPS to

measure seasonal elevation changes in the permafrost active layer on the Alaskan North Slope. The Barrow GPS base station was also utilized by this project during data collection in Barrow. The data were archived at UNAVCO after the field season.

Greenland Helheim Glacier (Jim Davis - Harvard Smithsonian) Twenty Trimble NetRS receivers (Figure 1�) were provided to study glacier-earthquake mechanisms. The receivers were

deployed on Helheim Glacier (Figure 13) in southeast Greenland, and collected high-rate data to measure deformation associated with “glacial earthquakes.” These events have been detected only in the past few years using global seismic data, which place only limited constraints on the process. The campaign was funded mainly by PI internal funds, with a data processing component funded by NSF-OPP. UNAVCO support was provided using NSF-EAR resources

Figure 12 (left) – Field testing GPS equipment prior to deployment. Photo: M. Nettles.

Figure 13 (right) - Helicopter landing at a glacier GPS site adjacent to a large and persistent melt pond. Photo: L. Stearns

Greenland Jakobshavn/Kangia Base Station (Bjorn Johns – UNAVCO) There is community interest in GPS base station data on rock in the Jakobshavn vicinity, both as a stable base for nearby

on-ice glaciology measurements and for direct measurement of the expected glacial isostatic adjustment resulting from the recent surge of Jakobshavn Isbrae. This proposed base station would be installed and operated by UNAVCO, with data readily available to all interested users. While the research permit application was denied this year due to the last minute nature of the request, a geodetic GPS monument was provided by UNAVCO and installed by Mark Fahnestock and Martin Truffer at their camp near the ice sheet margin on the north side of the glacier (Figure 14 and 15 ). Their project GPS data will be archived at UNAVCO with open data access, and the intent is to upgrade the GPS station for more permanent data collection and Iridium data telemetry early next field season. UNAVCO will provide the hardware necessary for this using NASA project funds available for this purpose.


Figure 1� (left) – UNAVCO facilitated the installation of a geodetic antenna monument near the Greenland ice sheet.

Figure 15 (right) – The bedrock location near the surging Kangia glacier is of interest both as a reference station for nearby glaciology research and to

measure glacial isostatic adjustment.

Greenland Peripheral Thinning (Tom Neumann – University of Vermont) This project is studying the role of meltwater on the peripheral thinning of the Greenland ice sheet. Ten Trimble R7

receivers were provided for the field season, and one of these will be left for the entire project durations to measure ice dynamics. This project was funded by the NASA Oceans and Ice program and UNAVCO support was via a sub-award from the University of Vermont.

Greenland Petermann Gletscher (Konrad Steffen – University of Colorado) One receiver was provided on a pre-season loan to test a new hardware controller (external timer) to enable custom

sessions for power conservation purposes. This project uses GPS for ice flow velocity and position measurements at Petermann Gletscher’s floating ice tongue as part the assessment of basal melt of Petermann Gletscher in northwest Greenland.

Greenland Summit GPS Base (Bjorn Johns - UNAVCO) A permanent GPS base station and rover system was installed at Summit Camp with real-time kinematic (RTK) surveying

capability. The system consists of a continuously operating base receiver and a roving receiver with ancillary equipment. In addition to providing precision mapping and topographic surveying capability, the system will also allow measurement of ice motion and yield data for atmospheric studies. While on-site, UNAVCO engineers Seth White and Thomas Nylen also performed two short surveys to update the position of the aircraft skiway and measure snow accumulation along a previously surveyed transect. A GPS monument was also installed on the GISP2 borehole casing to provide a reference point which is fixed to the underlying ice. GPS data from the site and a position time series are available on-line from UNAVCO. Pressure, temperature, humidity, and column water vapor data derived from GPS are available on-line from UCAR. See the Equipment diction of this report for more information regarding the Summit Camp GPS system

Greenland Supraglacial Lakes (Sarah Das – Woods Hole Oceanographic Institute) This project uses geophysical field measurements and remote sensing to investigate the role of Greenland’s supraglacial

lakes in delivering melt water to the ice sheet’s bed and in modulating ice flow on short time scales. Recent results demonstrate a correlation between ice velocity and surface melt draining through moulins to the bed, which may provide a mechanism for rapid response of the Greenland Ice Sheet to climate change. Supraglacial lakes are one of the critical links between surface melting and enhanced basal flow, have the potential to rapidly respond to future climate change, and are the focus of the research project. Five receivers, solar power systems, and enclosures were provided for a 15 month continuous deployment. The enclosure boxes (Figure 16) were built to also accommodate the seismic data logger system provided by IRIS.


Figure 16 (left) – Glacier boxes for easy set-up and long term continuous data collection designed specifically for this project will be incorporated in the UNAVCO equipment pool. Photo: I. Joughin.

Figure 17(right) – Survey of a transect across the South River study area.

Greenland Thule/Green Valley (Jeff Welker – University of Alaska Anchorage) The ICYLANDS project quantifies the coupling of the carbon and water cycles and the interacting physical, chemical,

and biological processes that control carbon exchange between cold, dry terrestrial ecosystems and the atmosphere. One of the main goals of this project is looking at carbon cycling by studying both the ecology and soil chemistry of Arctic ecosystems. UNAVCO provided field engineering support and four GPS receiver systems for: (1) measuring fixed points and (�) delineation of watershed boundaries and periglacial features. Bolts that were installed in �005 to measure the downslope movement of non-sorted stripes and solifluction lobes in Green Valley were re-measured to obtain solifluction velocity vectors. These measurements are the first GPS-based study of soil evolution in the high-Arctic, and centimeter-level displacements of several diverse soil features were demonstrated. In addition, six new monuments were installed in areas of particular interest based on the velocity results obtained. Further mapping operations were also completed, yielding a comprehensive survey of six study areas (Figure 17). These are the most pervasive periglacial forms in the high-Arctic and their formation is the primary mechanism by which soil organic carbon is brought to depth, and potentially brought up from depth at a later date. These are the first such measurements that have been made in the high-Arctic, and rates of these processes are as of yet poorly constrained.

Himalaya Ground Control Point (Adina Racoviteanu – University of Colorado) UNAVCO provided two older Trimble 4000 GPS receivers and a brief training session to this “community support” student

research project to acquire ground control points necessary for ortho-rectifying Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) satellite imagery in the Himalayas. Glaciers in mid-latitude areas of the world are important for water resources and sensitive indicators of changes in climate. There is a paucity of field-based measurements of glacier mass balance in high-mountain areas of Asia because of the difficulty of conducting field campaigns in rugged terrain, lack of logistical support and political or cultural conflicts. This limits our understanding of the alpine glacial response to climate variability. Remote sensing data from the ASTER instrument shows promise in filling existing gaps in field-based glacial measurements. A multi-scale approach will be used to test the suitability of ASTER images for glacier change detection from the basin scale to the regional scale in the Western Indian Himalayas. Specific objectives of the proposed research are: 1) to use a combination of remote sensing and traditional glaciological methods to estimate glacier mass-balance at the Chhota Shigri glacier; �) to construct an ASTER-based geospatial glacier inventory that will facilitate analysis of glacier changes at the regional scale; and 3) to understand spatial patterns of glacier fluctuations in relation to regional climatic variability across the entire Himalayan mountain range.


Iceland Breidamerkurjokull (Slawek Tulaczyk – University of California Santa Cruz) Solar panels and a GPS antenna were provided to this project to study the glacier-scale physics of soft-bedded ice motion.

One research objective is testing the hypothesis that the force balance and the rate of motion of Breidamerkurjokull on the Vatnajokull ice cap, Iceland is controlled by the underlying till bed and not by other factors such as sticky spots, longitudinal stretching/compression, and marginal shear. Understanding the physics that govern ice motion is needed to make predictions on the future behavior of mountain glaciers and ice sheets in the context of the ongoing climate change and sea-level rise. Breidamerkurjokull, an outlet glacier draining, has played a significant role in developing a new paradigm of glacier motion in which the ice itself rides passively on top of a deforming till bed. The data will be used to calculate the spatial distribution of basal shear stress and basal resistance. This research should improve the current understanding of ice-till interactions and of their control over flow of ice masses. It may also help predict whether modern ice masses will harm local or global societal interests through, for instance, changes in the global sea level or surges of mountain glaciers.

Kennicott Glacier (Robert Anderson – University of Colorado) Six GPS receivers, ancillary equipment, and training were provided to establish a local differential GPS network to monitor

glacial surface motion of the Kennicott Glacier during the melt season of �006. The base station was established in the town of McCarthy over an existing monument, while the other five monuments were drilled into the glacier surface. These were spread at several-km intervals to establish the evolving pattern of sliding both before and after the subglacial flood of Hidden Creek Lake. The stations were established in early summer, and maintained through the majority of the melt season until late August. This project was funded by NSF-EAR and NSF-OPP through an SGER grant, Glacial response to an outburst flood, Kennicott Glacier, Alaska.

McCall Glacier (Matt Nolan – University of Alaska, Fairbanks) Mass balance measurements, surface velocities, cross-

section profiles and continuous topography of McCall Glacier were made using real-time kinematic (RTK) surveys (Figure 18). The mass balance profiles were first measured in the 1990s with an airborne laser survey. These same points were re-occupied to determine vertical changes. The original network of velocity stakes was installed in �003 and since then has been measured twice a year. Five Trimble 5700/R7 receivers were left for the summer to capture temporal velocity variations. One of these receivers will be left over winter to determine late season variations. The research on the glacier is part of a multiyear project funded by the National Science Foundation’s Freshwater Initiative to study the hydrologic regimes of the several rivers flowing from the Brooks Range. Previous mass balance measurements on the glacier have been made during the International Geophysical Year in 1957-58, the International Hydrological Decade in 1969-1975 and the latter half of the 1990s. Because of this history, McCall Glacier has the longest monitoring record of any glacier in Arctic Alaska.

North Cascades (Erin Pettit – University of Washington) Three receivers were provided for this study to determine current glacier volumes and surface areas and to provide a

baseline for monitoring future changes of glaciers in Washington State. The work was in collaboration with Jon Riedel and the North Cascades National Park to augment and enhance their current glacier monitoring program. Another project goal is to study the dynamics of small alpine glaciers with respect to their sensitivity to changes in temperature and precipitation rates. A final goal of this project is to provide a small, well defined project to teach young women about field science through a program known as Girls on Ice, which is run through the North Cascades Institute. They will help with the research on Easton Glacier. These goals will be accomplished through GPS surface profiling (longitudinal and transverse), surface velocity measurements with repeat GPS measurements on stakes, and radar measurements of the glacier bed. UNAVCO support was made on a resource-available basis for this “community project.”

Figure 18 – Two skiers, equipped with RTK GPS equipment, set out to survey McCall Glacier.

�0 �006 UNAVCO Arctic Sciences Annual Report

St. Elias Erosion/Tectonics Project (STEEP) (Jeff Freymueller – University of Alaska, Fair-banks) The St. Elias Erosion/Tectonics Project (STEEP) is a multidisciplinary project to address the tectonics of the St. Elias

Range, Alaska, and the linkage between tectonism and erosion in major orogenic belts. This projects received funding from both NSF-EAR and NSF-OPP. UNAVCO provided eight receivers for the 2006 summer field season, and support for this project was provided by NSF-EAR resources.

Toolik Field Station Differential GPS System A Trimble 5700 real-time kinematic (RTK) differential GPS (DGPS) system is available for dedicated use at the Toolik

Field Station to meet the surveying needs of researchers working in the vicinity of Toolik Lake on the north side of Alaska’s Brooks Range. The real-time capability increases the system versatility in proximity of the station (for example it allows for stakeouts of pre-determined points), while the post-processing capability using Trimble Geomatics Office software extends the system radius to over 100km from the station. No major support was requested from UNAVCO this year due to the skilled and experienced GIS/GPS staff at Toolik Field Station, Lael Rogan and Andrew Balser.

�1 �006 UNAVCO Arctic Sciences Annual Report

Appendix B - Staff Time BreakdownTable 3 provides a coarse estimate of staff time for the major NSF-Arctic Sciences related tasks performed between 1 October �005 and 30 September �006 (FY06). UNAVCO is in the process of implementing a more detailed cost account-ing system that will allow the tracking of staff time directly to each task. The new system will provide much finer granularity for staff time reporting beginning with FY08 reports.

Table 3 – Estimate of Staff Weeks per Project and Task

Task Technician Engineering ManagementSupport to PI Projects:Arctic Tundra Thermocarst 0.5 0.5 0.�Barrow BAID-IMS 0.5 0.5 0.�Barrow Biocomplexity 0.5 0.5 0.�Bench Glacier 0.5 1 0.�Beringia 0.5 0.5 0.�Circumpolar Active Layer Monitoring 0.5 0.5 0.�Greenland Petermann Gletscher 0.5 0.�Greenland Supraglacial Lakes 0.5 � 0.�Greenland Thule/Green Valley 0.5 3 0.�Himalaya Ground Control 0.5 0.�Iceland Breidamerkurjokull 0.5 0.�Kennicott Glacier 0.5 0.5 0.�McCall Glacier 0.5 3 0.�North Cascades Glacier Monitoring 0.5 0.�

Support to Research Facilities: 1Atqasuk 0.5 1 1Barrow � � 1Summit 1 8Toolik 0.5

Infrastructure:Set up Boulder workshop �Jakobshavn GPS base � 1

Meetings:GeoSummit Workshop 1International Arctic Workshop 1UNAVCO Science Meeting 0.5European Geosciences Union 0.5Midwest Glaciology 1Virtual Globe Workshop 0.�Northwest Glaciology 1

Total FTE: 0�20 0�61 0�23

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