cometadata/datacite-titles-descriptions-related-identifiers huggingface dataset:
DOI: 10.18739/a2p55dh4m
title: Soil bacterial community and functional shifts in response to altered snow pack in moist acidic tundra of Northern Alaska

description: Soil microbial communities play a central role in the cycling of carbon (C) in Arctic tundra ecosystems, which contain a large portion of the global C pool. Climate change predictions for Arctic regions include increased temperature and
 precipitation (i.e. more snow), resulting in increased winter soil insulation, increased soil temperature and moisture, and shifting plant community composition. We utilized an 18-year snowfence study site designed to examine the effects of increased
 winter precipitation on Arctic tundra soil bacterial communities within the context of expected ecosystem response to climate change. Soil was collected from three pre-established treatment zones representing varying degrees of snow accumulation
 (DEEP, INT, LOW), soil physical properties (temperature, moisture, active layer thaw depth) were measured, and samples were analysed for C concentration, nitrogen (N) concentration, and pH. Soil microbial community DNA was extracted and the 16S rRNA
 gene was sequenced to reveal phylogenetic community differences between samples and determine how soil bacterial communities might respond (structurally and functionally) to changes in winter precipitation and soil chemistry. We analysed relative
 abundance changes of the six most abundant phyla (ranging from 82-96% of total detected phyla per sample) and found four (Acidobacteria, Actinobacteria, Verrucomicrobia, and Chloroflexi) responded to deepened snow. All six phyla correlated with
 at least one of the soil chemical properties (%C, %N, C:N, pH), however a single predictor was not identified suggesting that each bacterial phylum responds differently to soil characteristics. Overall bacterial community structure (beta
 diversity) was found to be associated with snow accumulation treatment and all soil chemical properties. Bacterial functional potential was inferred using ancestral state reconstruction to approximate functional gene abundance, revealing a decreased
 abundance of genes required for soil organic matter (SOM) decomposition in the organic horizon of the deep snow accumulation zones. These results suggest that predicted climate change scenarios may result in altered soil bacterial community structure
 and function, and indicate either a reduction in decomposition potential, or alleviated temperature limitations on extracellular enzymatic efficiency, or both. The fate of stored C in Arctic soils ultimately depends on the balance between these
 mechanisms.
DOI: 10.18739/a2jd4pq0g
title: Dissolved oxygen:argon gas ratio measured from the surface seawater flowthrough of USCGC Healy, October 2011

description: The purpose of this project was to assess ocean acidification in the western Arctic Ocean, using ship time that is currently scheduled for annual mooring turnarounds in the Beaufort Sea. On these cruises, in October of 2011-2013, the investigators collected samples for measurement of carbonate system parameters, inorganic nutrients, dissolved oxygen, oxygen isotopes, and oxygen/argon ratios, as well as continuous underway measurements of dissolved oxygen, oxygen/argon ratios, and pCO2. These data will be used to gain insights and perspectives into the extent of ocean acidification in the western Arctic Ocean; the key physical, chemical, and biological processes influencing the saturation states of aragonite and calcite; and potential impacts to pelagic and benthic communities.
 Measurement of the oxygen:argon gas ratio relative to saturation allows evaluation of net community metabolism (the balance between photosynthesis and respiration). Data were collected between October 3, 2011 and October 27, 2011 using an equilibrated inlet mass spectrometer connected to the USCGC Healy surface uncontaminated seawater supply. Nearly 15,000 datapoints were collected as the ship surveyed the Bering, Chukchi, and Beaufort sectors of the Pacific Arctic. The data file contains time, latitude, longitude, surface temperature, surface salinity, O2/Ar saturation, and O2 saturation.
DOI: 10.18739/a26z8q
title: Atmospheric hydrocarbons as tracers for climate change, air transport, and oxidation chemistry in the Arctic, GEOSummit, Greenland

description: This study is a contribution to the Arctic Observing Network (AON). It will undertake 4 years of continuous measurements of atmospheric methane, and non-methane hydrocarbons (NMHC; ethane, ethyne, propane, iso-butane, n-butane, iso-pentane, n-pentane, benzene, toluene) at the Greenland Environmental Observatory at Summit (GEOSummit). An existing monitoring system that has previously been operated at Summit for two seasons will be deployed. This gas chromatography instrument is specifically tailored towards operation at this remote arctic site, as it is fully automated and remotely controllable. This instrument uses a minimal amount of power and does not require cryogen and compressed gas supplies, which make it highly favorable and cost efficient for Summit conditions. A second analytical channel will be added to include monitoring of the important climate gas methane with the same instrument. Data are available through the World Data Center for Greenhouse Gases.
DOI: 10.18739/a2dn3zw6q
title: Atmospheric hydrocarbons as tracers for climate change, air transport, and oxidation chemistry in the Arctic, GEOSummit, Greenland

description: This study is a contribution to the Arctic Observing Network (AON). It will undertake 4 years of continuous measurements of atmospheric methane, and non-methane hydrocarbons (NMHC; ethane, ethyne, propane, iso-butane, n-butane, iso-pentane, n-pentane, benzene, toluene) at the Greenland Environmental Observatory at Summit (GEOSummit). An existing monitoring system that has previously been operated at Summit for two seasons will be deployed. This gas chromatography instrument is specifically tailored towards operation at this remote arctic site, as it is fully automated and remotely controllable. This instrument uses a minimal amount of power and does not require cryogen and compressed gas supplies, which make it highly favorable and cost efficient for Summit conditions. A second analytical channel will be added to include monitoring of the important climate gas methane with the same instrument. Data are available through the World Data Center for Greenhouse Gases.
DOI: 10.18739/a28w3831w
title: Collaborative research: What role do glaciers play in terrestrial sub-arctic hydrology?

description: The overall project assessed the linkages and controls of a subarctic glacier-permafrost hydrological system from a watershed-scale perspective using field measurements, remote sensing and numerical modeling. Jarvis Creek (634km2), which feeds the Delta and Tanana River in Interior Alaska, was studied as a proxy of the observed mountain glacier melting and permafrost degradation that has been documented across the Arctic region in recent decades. The specific objectives were to 1) assess the hydrologic fluxes (including streamflow source components), stores, pathways and the role of glacier wastage on watershed hydrology, through hydrologic and geochemical field measurements as well as numerical and statistical modeling; 2) quantify the effect of glaciers and permafrost on recent historical (1960-present) hydrologic fluxes and storage by combining remote sensing, field measurements of glacier mass balance, and hydrology with a heat- and mass transfer model, and 3) project the future hydrologic regime using custom-derived downscaled climate projections.
The purpose of this Ground-Penetrating Radar (GPR) data set was to 1) quantify winter snow accumulation hydrological contributions separately from the glacierized and non-glacierized regions of Jarvis Watershed; and, 2) estimate total glacier ice volume of Jarvis Glacier and, based on yearly mass balance calculations, estimate total future glacier contribution changes from Jarvis Glacier to hydrological discharge. Winter accumulation ranged between 1.1 to 1.9 m SWE during each of the three seasons. Jarvis Glacier ice volume calculated from geophysical surveys and a manually digitized glacier outline during late season 2015 was 1.16 km^3 within an area of 8.82 km^2.
DOI: 10.18739/a2542j88x
title: Atmospheric hydrocarbons as tracers for climate change, air transport, and oxidation chemistry in the Arctic, GEOSummit, Greenland, 2008-2017

description: This study is a contribution to the Arctic Observing Network (AON). It will undertake 4 years of continuous measurements of atmospheric methane, and non-methane hydrocarbons (NMHC; ethane, ethyne, propane, iso-butane, n-butane, iso-pentane, n-pentane, benzene, toluene) at the Greenland Environmental Observatory at Summit (GEOSummit). An existing monitoring system that has previously been operated at Summit for two seasons will be deployed. This gas chromatography instrument is specifically tailored towards operation at this remote arctic site, as it is fully automated and remotely controllable. This instrument uses a minimal amount of power and does not require cryogen and compressed gas supplies, which make it highly favorable and cost efficient for Summit conditions. A second analytical channel will be added to include monitoring of the important climate gas methane with the same instrument. Data are available through the World Data Center for Greenhouse Gases.
DOI: 10.18739/a21g0hv6m
title: A Large Ornithurine Bird (Tingmiatornis arctica) from the Turonian High Arctic: Climatic and Evolutionary Implications

description: Bird fossils from Turonian (ca. 90Ma) sediments of Axel Heiberg Island (High Canadian Arctic) are among the earliest North American records. The morphology of a large well-preserved humerus supports identification of a new volant, possibly diving, ornithurine species (Tingmiatornis arctica). The new bird fossils are part of a freshwater vertebrate fossil assemblage that documents a period of extreme climatic warmth without seasonal ice, with minimum mean annual temperatures of 14°C. The extreme warmth allowed species expansion and establishment of an ecosystem more easily able to support large birds, especially in fresh water bodies such as those present in the Turonian High Arctic. Review of the high latitude distribution of Northern Hemisphere Mesozoic birds shows only ornithurine birds are known to have occupied these regions. We propose physiological differences in ornithurines such as growth rate may explain their latitudinal distribution especially as temperatures decline later in the Cretaceous. Distribution and physiology merit consideration as factors in their preferential survival of parts of one ornithurine lineage, Aves, through the K/Pg boundary.
 Digital files of an open access manuscript and supplemental materials file and digital copies of figures that went into the manuscript are included with this data set upload. Samples were collected during field seasons on Axel Heiberg Island. Cat scan imagery was conducted at the University of Texas, Austin. Three animations resulting from cat scan imagery are included.
DOI: 10.18739/a2wp9t72k
title: Asynchrony in the timing of goose-vegetation interactions: implications for biogeochemical cycling in wet sedge tundra Tutakoke River, Yukon Delta NWR, Alaska, 2014-2016

description: Data were collected from a three-year manipulative experiment investigating the interacting effects of changes in plant phenology and timing of goose grazing on subarctic graminoid grazing lawns in the Yukon Delta NWR, Alaska, USA. 
 Terrestrial high-latitude ecosystems are experiencing dramatic increases in temperature, changes in precipitation, and advancement of the growing season with important implications for trophic interactions. Uncoupling of the temporal relationships between migratory animals and the phenology of the forage they rely on for energy, nutrition, and rearing of young is one of the most glaring consequences of these changes. Furthermore, herbivores in high latitudes are likely to mediate biogeochemical responses to climate change substantially altering ecosystem function. However, little is known about how changes in the synchrony of herbivore-vegetation interactions will influence biogeochemical cycles.
 This research was conducted in the Yukon-Kuskokwim (Y-K) Delta in western Alaska, where there is strong evidence that climate change is driving temporal decoupling of the evolved linkage between the phenology of plants and the timing of goose migration. There is an urgency to the research because: 1) some of the most rapid climate changes in the world are underway in Alaska, leaving migratory geese and the ecosystem processes they influence vulnerable to new conditions, and 2) with the rapid advancement of the growing season, migratory goose feeding ecology is lagging substantially, threatening an irreplaceable subsistence resource for Native communities.
 The overall research objective is to quantify how an advancing growing season and changes in the synchrony of vegetation-goose interactions alter the magnitudes and patterns of C and N cycling in the YK Delta. Our specific research questions addressed with an experiment were: 1) How does the timing of plant growth interact with goose arrival time to alter summer-long magnitudes of plant production, foliar chemistry, and N availability? and 2) How does the timing of plant growth interact with goose arrival time to alter summer-long magnitudes of net ecosystem CO2 exchange, gross ecosystem photosynthesis, and ecosystem respiration?
DOI: 10.18739/a2rx93d9p
title: Geophysical data from the Disko and Nuussuaq ice caps, Greenland, 2014

description: This submission includes data used in the selection of sites for ice coring on the Disko (69.6607N, 52.7379W) and Nuussuaq ( 70.4891N, 152.2665W) ice caps in Western Greenland. For the Disko site, fieldwork was conducted April 21, 2014, and for the Nuussuaq site on April 24, 2014. At each site, workers drilled a 10-meter firn core while a roped team of three workers conducted an ice-penetrating and ground-penetrating radar survey on the south-east face of the ice cap. The ice-core data have been submitted separately, this submission contains ground-penetrating and ice-penetrating radar data, primarily for the Nuussuaq site where a 140-meter ice core was later drilled. We also include surface-elevation DEM data derived from satellite photogrammetric techniques. 

 Data are provided in the raw DZT format provided by the radar system, which can be read using proprietary GSSI software or using the included matlab script ‘read_dzt.m.’ For convenience, we have also provided the data concatenated into a large HDF5 file which provides filtered data, geolocation and timing information for each trace within the survey, and pick information.
DOI: 10.18739/a2n58cm5v
title: Collaborative Research: Contrasting Under-Ice and Open-Water Phytoplankton Blooms in the Chukchi Sea, Arctic, 2014

description: Over the last several decades, Arctic Ocean ice cover has become substantially thinner and more prone to melting, extending the period of open water. Associated with the loss of sea ice has been an increase in light penetration and a dramatic rise in the productivity of phytoplankton. The PIs' primary objectives are to determine the spatial distribution of large under-ice phytoplankton blooms on the Chukchi Shelf and the physical mechanisms that control them. The project proposed herein will utilize new data obtained from both remote instrumentation (e.g. moorings and satellites) and an interdisciplinary ship-based field program to gain a better understanding of the physical/chemical conditions that favor under-ice bloom development as well as the physiological adaptations that allow phytoplankton to flourish beneath sea ice. Outreach and education components of this project include participation in Stanford's Summer Program for Professional Development for Science Teachers and Stanford's School of Earth Sciences high school internship program, a compilation of professionally written short stories in the website by the Woods Hole Oceanographic Institution group, and incorporation of results by the Cold Regions Research and Engineering Laboratory.
DOI: 10.18739/a2hd7nt1q
title: Dissolved oxygen:argon gas ratio measured from the surface seawater flowthrough of USCGC Healy, October 2012

description: The purpose of this project was to assess ocean acidification in the western Arctic Ocean, using ship time that is currently scheduled for annual mooring turnarounds in the Beaufort Sea. On these cruises, in October of 2011-2013, the investigators collected samples for measurement of carbonate system parameters, inorganic nutrients, dissolved oxygen, oxygen isotopes, and oxygen/argon ratios, as well as continuous underway measurements of dissolved oxygen, oxygen/argon ratios, and pCO2. These data will be used to gain insights and perspectives into the extent of ocean acidification in the western Arctic Ocean; the key physical, chemical, and biological processes influencing the saturation states of aragonite and calcite; and potential impacts to pelagic and benthic communities.
 Measurement of the oxygen:argon gas ratio relative to saturation allows evaluation of net community metabolism (the balance between photosynthesis and respiration). Data were collected between October 5, 2012 and October 25, 2012 using an equilibrated inlet mass spectrometer connected to the USCGC Healy surface uncontaminated seawater supply. Over 9,000 datapoints were collected as the ship surveyed the Bering, Chukchi, and Beaufort sectors of the Pacific Arctic. The data file contains time, latitude, longitude, surface temperature, surface salinity, O2/Ar saturation, and O2 saturation.
DOI: 10.15468/dl.4y59tk
title: Occurrence Download

description: A dataset containing 29 species occurrences available in GBIF matching the query:
{
 "and" : [
 "HasGeospatialIssue is false",
 "HasCoordinate is true",
 "OccurrenceStatus is Present",
 {
 "not" : {
 "BasisOfRecord" : [
 "is one of (Fossil, Living Specimen)"
 ]
 }
 },
 "TaxonKey is one of (Nannoglottis hookeri (C.B.Clarke ex Hook.fil.) Kitam.)"
 ]
}

 The dataset includes 29 records from 8 constituent datasets; see https://api.gbif.org/v1/occurrence/download/0027740-241107131044228/datasets/export for details.
 
Data from some individual datasets included in this download may be licensed under less restrictive terms.
DOI: 10.18739/a2cn6z06w
title: Contrasting Under-Ice and Open-Water Phytoplankton Blooms, Chukchi Sea, Arctic, 2014

description: Over the last several decades, Arctic Ocean ice cover has become substantially thinner and more prone to melting, extending the period of open water. Associated with the loss of sea ice has been an increase in light penetration and a dramatic rise in the productivity of phytoplankton. The PIs' primary objectives are to determine the spatial distribution of large under-ice phytoplankton blooms on the Chukchi Shelf and the physical mechanisms that control them. The project proposed herein will utilize new data obtained from both remote instrumentation (e.g. moorings and satellites) and an interdisciplinary ship-based field program to gain a better understanding of the physical/chemical conditions that favor under-ice bloom development as well as the physiological adaptations that allow phytoplankton to flourish beneath sea ice. Outreach and education components of this project include participation in Stanford's Summer Program for Professional Development for Science Teachers and Stanford's School of Earth Sciences high school internship program, a compilation of professionally written short stories in the website by the Woods Hole Oceanographic Institution group, and incorporation of results by the Cold Regions Research and Engineering Laboratory. This specific data set contrasts under-ice and open-water phytoplankton blooms in the Chukchi Sea.
DOI: 10.18739/a27w6763m
title: Late spring nitrate distributions beneath the ice-covered northeastern Chukchi Shelf, Chukchi Sea Arctic, 2014

description: Over the last several decades, Arctic Ocean ice cover has become substantially thinner and more prone to melting, extending the period of open water. Associated with the loss of sea ice has been an increase in light penetration and a dramatic rise in the productivity of phytoplankton. The PIs' primary objectives are to determine the spatial distribution of large under-ice phytoplankton blooms on the Chukchi Shelf and the physical mechanisms that control them. The project proposed herein will utilize new data obtained from both remote instrumentation (e.g. moorings and satellites) and an interdisciplinary ship-based field program to gain a better understanding of the physical/chemical conditions that favor under-ice bloom development as well as the physiological adaptations that allow phytoplankton to flourish beneath sea ice. Outreach and education components of this project include participation in Stanford's Summer Program for Professional Development for Science Teachers and Stanford's School of Earth Sciences high school internship program, a compilation of professionally written short stories in the website by WHOI group, and incorporation of results by CRREL.
DOI: 10.18739/a24746s04
title: Ice temperatures measured in a grid of boreholes, Western Greenland, 2014-2016

description: Ice in the ablation zone of the Greenland ice sheet is known to contain vertical temperature gradients that arise from conduction at the boundaries, the addition of strain and latent heat, and advective heat transport. A three‐dimensional array of temperature measurements in a grid of boreholes reveals horizontal ice temperature gradients that challenge the present conceptualization of heat transfer. We measure two distinct types of temperature variability in the horizontal direction, one impacting a confined region where ice temperatures span a range of 5°C, and another with temperatures consistently varying by approximately 2°C across the entire 3‐D block. We suggest the first demonstrates the localized and limited nature of latent heat input, and the second demonstrates that vertical heat advection outpaces diffusion. These findings imply that ice flow is highly variable over sub‐ice‐thickness length scales, which in turn generates contrasts in ice temperature that may impact ice deformation and fracturing.
DOI: 10.18739/a20g3gz7v
title: Borehole water temperature measurements during drilling in Western Greenland, 2014

description: This dataset contains time-series measurements of simultaneous
 borehole water and drill water temperature, measured in an instrumented
 drill stem during hot water drilling of boreholes in western Greenland.
 Ice deformation is concentrated at depth, and the processes dictating
 ice sheet sliding depend on the physical condition of the ice sheet bed,
 but the remote nature of deep ice conditions severely limits observation.
 This motivates novel measurements to maximize the information content in
 boreholes which directly access the ice sheet bed but are logistically
 and technically challenging. Time series of borehole water temperatures
 provide an additional test of the abruptness of the basal boundary
 (Harper et al., 2017), and thermal dissipation is also used as a measure
 to constrain resident water volume at the ice sheet bed (Meierbachtol et
 al., 2016).
 
Harper J, Humphrey N, Meierbachtol T, Graly J and Fischer U (2017) Borehole Measurements Indicate Hard Bed Conditions, Kangerlussuaq Sector, Western Greenland Ice Sheet. J. Geophys. Res. Earth Surf. (doi:10.1002/2017JF004201)

 
Meierbachtol TW, Harper JT, Humphrey NF and Wright PJ (2016) Mechanical forcing of water pressure in a hydraulically isolated reach beneath Western Greenland ablation zone. Ann. Glaciol. 57(72), 62-70 (doi:10.1017/aog.2016.5)