Continued Core Atmospheric and Snow Measurements at the Summit, Greenland Environmental Observatory (Neumann)

Researchers under the Neumann ICESat project will study snow accumulation measured year-round at the Greenland Environmental Observatory at Summit Station (GEO Summit), an effort that continues measurement programs previously supported under PI McConnell (NSF grant 0856845). The project involves two staked arrays: the 121-stake (11 x 11) ‘bamboo forest’ near the station, commencing about 700 meters east of the Station Operations Facility, which is measured weekly; and the 121-stake linear array for NASA’s Ice, Cloud, and land Elevation Satellite (ICESat) and ICESat-2 validation, commencing about 3,300 meters west of the Station Operations Facility, which is measured monthly. The ICESat GPS land elevation validation snow machine transect was started in 2006 along the satellite track of the laser altimeter and has continued during the interim period between the end of the mission of the original ICESat in 2009 and the 2018 launch of ICESat-2. Results improve understanding of ice sheet elevation change and snow-water equivalencies. Beginning in 2016, Summit Station science technicians will collect snow accumulation values for comparison to measurements of ground and remote sensing instrumentation. This effort continues measurement programs previously supported under PI McConnell (NSF grant 0856845).

In 2017, Co-PI Kelly Brunt visited Summit in June to assess the existing ICESat survey line and procedures carried out by the science technicians. Science technicians coordinated with her and the GreenTracs traverse team to conduct the required surveys. The ICESat-2 extension of the snowmachine transect was added to the survey route. Researchers did not visit Greenland in the years 2018 through 2021. In 2022, close collaborators of the project traveling under PI Hawley (NSF grant 2028421) installed an ApRES radar instrument along the ICESat-2 validation transect and constructed a second survey sled equipped with GNSS equipment to be towed during the monthly ICESat validation snow machine surveys. In 2023, one science team member traveled to Summit Station to uninstall and collect data from the ApRES radar, as well as to test laser distance sensors designed to be incorporated in an upgraded survey sled for future ICESat surveys. In 2024, one science team member and close collaborators of the project traveling under PI Hawley (NSF grant 2028421) traveled to Summit Station to test and install a laser distance sensor package on the ICESat survey sled, performed a mapping survey of the Bamboo Forest staked array, and decommissioned nine autonomous OGRE GNSS instruments installed off-station by the Hawley 2028421 project. Annual maintenance was performed for four OGRE instruments that were not decommissioned in 2024. Ownership of these OGRE instruments, including three installed along the ICESat survey route and one installed within the Bamboo Forest staked array, was transferred to the Neumann ICESat project.

In 2025, two science team members will travel to Summit Station to perform annual maintenance of four existing OGRE instruments and install six additional OGRE instruments near the end of the ICESat survey route. The science team will use two snowmobiles and the PolyPod towable shelter to visit the off-station sites in a series of day trips from Summit Station. The science team will also perform a mapping survey and raise of the Bamboo Forest staked array and service the SLIVER instrument deployed during year-round ICESat surveys. While working at Summit Station, the science team will utilize one of the benches in the Mobile Science Facility (MSF) and an arctic oven tent installed outside of the MSF as workspace.

Battelle ARO will provide science technician support, communications equipment, snowmachines, fuel, and shared use of EarthScope GPS instrumentation in support of year-round ICESat and Bamboo Forest surveys. In years with researcher visits to Greenland, Battelle ARO will provide Air National Guard coordination for passengers and cargo, Greenland departure fees, Summit Station user days, Kangerlussuaq lodging, snowmobiles, fuel, and use of communications and safety gear from NSF inventory. NSF will recoup costs of this support via an interagency funds transfer from NASA to NSF. All other logistics will be arranged and paid for by the research group from the grant.