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Abstract. Soil water isotope datasets are useful for understanding connections between the hydrosphere, atmosphere, biosphere, and geosphere. However, they have been underproduced because of the technical challenges associated with collecting those datasets. Here, we present the results of testing and automation of the Soil Water Isotope Storage System (SWISS). The unique innovation of the SWISS is that we are able to automatically collect water vapor from the critical zone at a regular time interval and then store that water vapor until it can be measured back in a laboratory setting. Through a series of quality assurance and quality control tests, we tested whether the SWISS is resistant to both atmospheric intrusion and leaking in both laboratory and field settings. We assessed the accuracy and precision of the SWISS through a series of experiments in which water vapor of known composition was introduced into the flasks, stored for 14 d, and then measured. From these experiments, after applying an offset correction to report our values relative to Vienna Standard Mean Ocean Water (VSMOW), we assess the precision of the SWISS to be ±0.9 ‰ and ±3.7 ‰ for δ18O and δ2H, respectively. We deployed three SWISS units at three different field sites to demonstrate that the SWISS stores water vapor reliably enough that we are able to differentiate dynamics both between the sites as well within a single soil column. Overall, we demonstrate that the SWISS retains the stable isotope composition of soil water vapor for long enough to allow researchers to address a wide range of ecohydrologic questions. 

Abstract. Above polar ice sheets, atmospheric water vapor exchangeoccurs across the planetary boundary layer (PBL) and is an importantmechanism in a number of processes that affect the surface mass balance ofthe ice sheets. Yet, this exchange is not well understood and hassubstantial implications for modeling and remote sensing of the polarhydrologic cycle. Efforts to characterize the exchange face substantiallogistical challenges including the remoteness of ice sheet field camps,extreme weather conditions, low humidity and temperature that limit theeffectiveness of instruments, and dangers associated with flying mannedaircraft at low altitudes. Here, we present an unmanned aerial vehicle (UAV)sampling platform for operation in extreme polar environments that iscapable of sampling atmospheric water vapor for subsequent measurement ofwater isotopes. This system was deployed to the East Greenland Ice-coreProject (EastGRIP) camp in northeast Greenland during summer 2019. Foursampling flight missions were completed. With a suite of atmosphericmeasurements aboard the UAV (temperature, humidity, pressure, GPS) wedetermine the height of the PBL using online algorithms, allowing forstrategic decision-making by the pilot to sample water isotopes above andbelow the PBL. Water isotope data were measured by a Picarro L2130-iinstrument using flasks of atmospheric air collected within the nose cone ofthe UAV. The internal repeatability for δD and δ18O was2.8 ‰ and 0.45 ‰, respectively,which we also compared to independent EastGRIP tower-isotope data. Based onthese results, we demonstrate the efficacy of this new UAV-isotope platformand present improvements to be utilized in future polar field campaigns. Thesystem is also designed to be readily adaptable to other fields of study,such as measurement of carbon cycle gases or remote sensing of groundconditions. 

This data set is part of a joint international effort for the East GReenland Ice-core Project (EGRIP), which has retrieved an ice core by drilling through the Northeast Greenland Ice Stream (NEGIS, 75.63°N (North), 35.98°W (West)). Ice streams are responsible for draining a significant fraction of the ice from the Greenland Ice Sheet (GIS), and the project was developed to gain new and fundamental information on ice stream dynamics, thereby improving the understanding of how ice streams will contribute to future sea-level change. The drilled core also provides a new record of past climatic conditions from the northeastern part of the GIS. The project has many international partners and is managed by the Centre for Ice and Climate, Denmark with air support carried out by US ski-equipped Hercules aircraft managed through the US (United States) Office of Polar Programs, National Science Foundation. As of May 2022, approximately 2099.2 m (meters) of ice core have been recovered from the combined efforts of drilling operations in 2017, 2018, and 2019. Here we present records of stable isotopes of oxygen and hydrogen from 21.5 meters to 2120.7 m depth. Bedrock is estimated to be at a depth of approximately 2550 m; the remaining ice is expected to be recovered in the 2022 and 2023 field seasons. The data product presented here is supported by the National Science Foundation project: Collaborative Research: The fingerprint of abrupt temperature events throughout Greenland during the last glacial period. Award # 1804098. 

This data set is part of a joint international effort for the East GReenland Ice-core Project (EGRIP), which has retrieved an ice core by drilling through the Northeast Greenland Ice Stream (NEGIS, 75.63°N (North), 35.98°W (West)). Ice streams are responsible for draining a significant fraction of the ice from the Greenland Ice Sheet (GIS), and the project was developed to gain new and fundamental information on ice stream dynamics, thereby improving the understanding of how ice streams will contribute to future sea-level change. The drilled core also provides a new record of past climatic conditions from the northeastern part of the GIS. The project has many international partners and is managed by the Centre for Ice and Climate, Denmark with air support carried out by US ski-equipped Hercules aircraft managed through the US (United States) Office of Polar Programs, National Science Foundation. As of May 2022, approximately 2099.2 m (meters) of ice core have been recovered from the combined efforts of drilling operations in 2017, 2018, and 2019. Here we present records of stable isotopes of oxygen and hydrogen from 21.5 meters to 2120.7 m depth. Bedrock is estimated to be at a depth of approximately 2550 m; the remaining ice is expected to be recovered in the 2022 and 2023 field seasons. The data product presented here is supported by the National Science Foundation project: Collaborative Research: The fingerprint of abrupt temperature events throughout Greenland during the last glacial period. Award # 1804098. 

Summit Station Science Summit; Arlington, Virginia, 28–29 March 2017