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Erich Osterberg, Gabe Lewis, and Thomas Overly have returned from Greenland and a highly successful first year of the GreenTRaCs traverse! See the full story on Gabe's blog!

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Last updated 06.13.2016

WORKSHOP: the future shape of a Greenland GNSS observation network.

25-26 January, 2017 at NASA Goddard Space Flight Center

We had a great workshop- thanks to all who participated!

Presentations from invited speakers are available here.

Subsequent to the workshop, a subgroup of authors drafted a whitepaper on how best to move GNET forward- a PDF of this paper is now available here.

WEB REGISTRATION FOR THIS WORKSHOP HAS NOW CLOSED. If you are interested in attending, note that the deadline for obtaining access to Goddard Space Flight Center for the workshop has passed, even for US citizens (see PARCA link at bottom of page). For further information, please email Bob (robert.hawley(at)

There is no fee for this workshop, and for those in need there is a small amount of travel funding available.

We will convene a 1 1/2 day workshop at NASA Goddard Space Flight Center in January 2017 (directly following PARCA 2017), with the purpose of defining a path forward for a Global Navigation Satellite System (GNSS) observation network in Greenland. There are many means for determining Greenland ice mass loss, but almost all rely on some form of satellite positioning, generally using GNSS or its subset Global Positioning System (GPS). Thus a network of geodetic-quality GNSS receivers is desirable.

Such a network already exists in the form of GNET, a joint US/Danish network of GPS receivers. Existing funding for GNET is drawing to a close, and the future of the network remains uncertain. Thus it is important to bring the various stakeholders and potential users of these data together to define the system requirements and the path forward.

The goals of the workshop are:

  1. Elucidate the current state of the network
  2. Illustrate the current uses of network data (eg. Geodessey, Crustal deformation, Campaign GNSS reference, atmospheric modeling, Space weather/ionosphere. )
  3. Identify potential new utility of the data
  4. Determine the optimal configuration moving forward: Ideal number of stations, Placement of stations, Replacement and upgrade of stations, Data management.

The workshop will bring together:

  1. Investigators using data produced by the current network,
  2. Potential new investigators who can make use of GNSS network data,
  3. Experts in the use of GNSS data for positioning,
  4. Experts in the use of GNSS as a remote-sensing tool (atmospheric water vapor, ionospheric electron content, and multipath utilization for sensing of conditions prox- imal to the station such as snow depth, vegetation, and mapping of transient areas covered by liquid water), and
  5. The people involved in actually deploying GNSS reference stations around Greenland.

Both NSF and NASA program officers will also be invited to attend. Together, this group will have the breadth and depth to accomplish the goals of the workshop.

We look forward to seeing you there!

Bob Hawley, Tom Neumann, and Erik Ivins
(organizing committee)

Tentative Schedule and Registration

Registration for GNET 2017

Wednesday, 25 Jan- Day 1
Morning -- Plenary

  • Overview of history and current state of GNET
  • GNSS data for geodetic studies of surface elevation and motion
  • GNSS data as reference data for aircraft trajectory processing
  • Use of GNSS ground stations as altimetric control for space- and air-borne altimetry studies
  • Use of low-level GNSS data for studies of tropospheric path delays
  • GNSS data in studies of the Ionosphere and space weather
  • GNSS data as control points in lithospheric modeling
  • Use of GNSS data to constraint space-borne gravimetric studies of ice sheet mass balance
  • Data management and stewardship-best practices

Afternoon -- Breakout groups - one for each of several topics

  • Solid earth studies
  • Use as reference receivers for on-ice or aircraft studies
  • Ionospheric and tropospheric studies
  • Data management and stewardship
  • All others
Reports of breakout groups and full-meeting discussion

Thursday, 26 Jan- Day 2; half-day Subgroups work on actual whitepaper sections. First draft of complete report


This workshop follows the PARCA workshop at NASA Goddard, held on Tuesday, 24 January 2017. For travel and lodging information please refer to the PARCA 2017 website. In particular, note that access to Goddard Space Flight Center requires documentation to be submitted to NASA in advance see the PARCA page for details.