cometadata/datacite-titles-descriptions-related-identifiers huggingface dataset:
DOI: 10.18739/a2p55dj23
title: North Pacific and Arctic Marine Vessel Traffic Dataset (2015-2020)

description: These data are a spatially explicit representation of monthly shipping intensity in the Pacific Arctic region from January 1, 2015 to December 31, 2020. We calculated shipping intensity based on Automatic Identification System (AIS) data, a type of Global Positioning System (GPS) transmitter required by the International Maritime Organization on all ships over 400 gross tonnes, all ships over 300 gross tonnes on an international voyage, and all passenger ships. We used AIS data received by the exactEarth satellite constellation (64 satellites as of 2020), ensuring spatial coverage regardless of national jurisdiction or remoteness. Our analytical approach converted raw AIS input into monthly raster and vector datasets, separated by vessel type. We first filtered raw AIS messages to remove spurious records and GPS errors, then joined remaining vessel positional records with static messages including descriptive attributes. We further categorized these messages into one of four general ship types (cargo; tanker; fishing; and other). For the vector dataset, we spatially intersected AIS messages with a hexagon (hex) grid and calculated the number of unique ships, the number of unique ships per day (summed over each month), and the average and standard deviation of the speed over ground. We calculated these values for each month for all vessels as well as vessels subdivided by ship type and for messages from vessels &gt;65 feet long and traveling &gt;10 knots. For the raster dataset, we created a series of spatially explicit daily vessel tracks according to unique voyages and aggregated tracks by ship type and month. We then created a raster grid and calculated the total length, in meters, of all vessel tracks within each raster cell. These monthly datasets provide a critical snapshot of dynamic commercial and natural systems in the Pacific Arctic region. Recent declines in sea ice have lengthened the duration of the shipping season and have expanded the spatial coverage of large vessel routes, from the Aleutian Islands through the Bering Strait and into the southern Chukchi Sea. As vessel traffic has increased, so has exposure to the myriad environmental risks posed by large ships, including oil spills, underwater noise pollution, large cetacean ship-strikes, and discharges of pollutants. This dataset provides scientific researchers, local community members, mariners, and decision-makers with a quantitative means to evaluate the distribution and intensity of shipping across space and through time.
DOI: 10.18739/a2p843x4x
title: A survey of 2015 Alaska seaplane operations with predictions of transmission risk for aquatic invasive plants.

description: The main purpose of the survey was to establish the risk domain for introducing Elodea, an aquatic invasive species, by identifying unique seaplane destinations, flight origin, and annual flight frequency. We designed an electronic mapping tool programmed in JavaScript and using Mapbox Outdoors general-purpose maps (see Figure). The mapping tool enabled precise identification of flying destinations while avoiding spatial ambiguity. We first asked pilots to tell us their home base and then mark their 2015 first-leg freshwater destinations using the mapping tool. Once respondents placed the electronic marker, a pop-up menu asked the pilot to state the 2015 annual flights to the marked destination from their home base using the following intervals: less than 10, 10–25, 25–50, 50–75, 75–100, and more than 100 (Schwoerer et al., 2019). Our targeted population included pilots who flew seaplanes in Alaska in 2015, excluding Southeast Alaska. The sampling considered three pilot groups consisting of pilots who fly seaplanes for personal reasons, commercially, and for the government. We use a hierarchical Bayesian probability model to estimate transmission risk and associated uncertainty for each of 727 seaplane destinations that survey respondents identified.
DOI: 10.18739/a2pc2t997
title: Consolidated surface moisture budget measurements from high-latitude flux tower sites at daily, weekly, and monthly time periods, 1995-2019.

description: This dataset contains in situ measurements of the atmosphere-surface moisture fluxes (precipitation, evapotranspiration) and the associated atmospheric drivers of evapotranspiration at 45 terrestrial sites in northern high latitudes. For each site, the raw measurements for 30-minute periods have been aggregated into daily, weekly and monthly averages of the atmospheric variables and daily totals of precipitation (P) and evapotranspiration (ET). The dataset is intended to facilitate diagnostic studies of the variations of the surface moisture balance over timescales of days to seasons. All sites have at least 3 years of data and are distributed as follows: Canada (10), Alaska (17), Russia (8), Finland (2), Sweden (3), Svalbard (1), Greenland (3), Iceland (1). Atmospheric variables include air temperature (2-meter), relative humidity, wind speed, sensible heat flux, ground heat flux, net shortwave radiation and net longwave radiation. Useful data are generally limited to the warm season (April/May through September/October). An auxiliary file includes the key descriptors for each site: AmeriFlux/FluxNet site name and identifier, latitude-longitude, years of data coverage, dominant vegetation type, and the presence or absence of permafrost.
DOI: 10.18739/a2pk0734d
title: Terrestrial carbon, water and energy fluxes measured by eddy covariance, and associated biomet variables, at three adjacent tundra ecosystems at Imnavait Creek, Alaska, 2019

description: This Arctic Observing Network (AON) project focuses on maintaining and expanding our long-term network of measurements of carbon, water, and energy exchange in terrestrial systems in Alaska. These exchanges help regulate the Arctic System and its feedbacks to global climate. Thus, extending long-term observations is a key science priority for the observing-change component of the Study of Environmental Arctic Change (SEARCH). Detecting and interpreting change in arctic C, water, and energy fluxes requires a continuous year-round record over multiple years. Recent data syntheses and modeling studies of Arctic Carbon balance suggest that tundra is either a carbon dioxide (CO2) sink, a source, or neutral (e.g., McGuire et al., 2009, McGuire et al., 2012) . This uncertainty arises mainly from a lack of data on winter CO2 flux and how tundra responds to recent warming. Because of harsh, remote environments and the lack of line power, long-term measurements of arctic CO2 fluxes over the full year are rare. We have been measuring year-round C, water, and energy fluxes for eleven years in two broadly representative flagship observatories with long-term histories of research, at Imnavait Creek near Toolik Lake, Alaska, and near Cherskiy, Siberia. Similar versions of these eddy covariance and biomet data are available from Ameriflux as sites US-ICx. https://ameriflux.lbl.gov/data/download-data/ Our three Imnavait Creek Alaska sites retained multiple names over the years. The following clarification is needed. The 'official' site name is followed by the technical station name (IC_xxxx), the positional name (Ridge), and the Ameriflux site name (US-ICx), and finally the site coordinates. Wet Sedge tundra (IC_1523, Fen, US-ICs) 68.6058 -149.3110 Tussock tundra (IC_1993, Tussock, US-ICt) 68.6063 -149.3041 Dry Heath tundra (IC_1991, Ridge, US-ICh) 68.6068 -149.2958
DOI: 10.18739/a2pn8xg88
title: Benthic macroinfaunal samples collected from the Canadian Coast Guard Ship (CCGS) Sir Wilfrid Laurier, Northern Bering Sea to Chukchi Sea, 2019

description: The Pacific sector of the Arctic Ocean is experiencing major reductions in seasonal sea ice extent and increases in sea surface temperatures. One of the key uncertainties in this region is how the marine ecosystem will respond to seasonal shifts in the timing of spring sea ice retreat and/or delays in fall sea ice formation. Variations in upper ocean water hydrography, planktonic production, pelagic-benthic coupling and sediment carbon cycling are all influenced by sea ice and temperature change. To more systematically track the broad biological response to sea ice retreat and associated environmental change, an international consortium of scientists have developed a coordinated “Distributed Biological Observatory” (DBO) that includes selected biological measurements at multiple trophic levels, along with satellite and mooring measurements. The DBO currently focuses on five regional biological “hotspot” locations along a latitudinal gradient that allows for consistent sampling and monitoring at five biologically productive locations across a latitudinal gradient: DBO 1 (SLIP)-south of St. Lawrence Island (SLI), DBO2 (Chirikov)-north of SLI, DBO3 (southern Chukchi Sea), DBO4-NE Chukchi Sea,and DBO5-Barrow Canyon. This dataset contains benthic macroinfaunal population level from sediment samples collected at each station for the United States Coast Guard Cutter (USCGC) Healy cruise-Leg 1 in 2017, identified by station number (#), Station name (Stn. Name), Date (mm/dd/yy), latitude (°N), longitude (°W), and station depth (m). The following macroinfaunal parameters were determined: abundance, wet weight biomass (grams of wet weight per meters squared), dry weight biomass (grams of Carbon per meters squared), and taxon type.
DOI: 10.18739/a2pr7mw0q
title: Water Stage and Discharge of a Supraglacial Stream in Southwest Greenland (67.15N, 50.00W) Each Minute from July 13, 2019 to August 10, 2019

description: A small supraglacial stream in Southwest Greenland was observed for a 29-day period during the melt season of 2019. A Solinst Levellogger pressure transducer continuously measured stage height every minute throughout the observation period. The logger was placed in a RACO-2 metal project box filled with rocks with conduit holes knocked out to allow water to easily flow through. The box was anchored to a PVC pole drilled into the thalweg of the stream channel. Stage heights were corrected for atmospheric presssure using a Solinst Barologger located 2 m above the ice surface of the adjacent shore. Water heights were also collected with a meter stick at the location of the logger periodically throughout the field season in order to correct for measurement drift and systematic instrumentation error. The measurements showed that water level varied between 0.02 and 0.36 meter (m) fluctuating diurnally. Daily averaged water level peaked on August 1st. Additionally to the water stage heights, stream discharge was recorded with a Sontek FlowTracker2 Handheld Acoustic Doppler Velocimeter on 33 occasions throughout the observation period. Measurements were used to create a rating curve relating stage to discharge in an exponential relationship. The relationship was used to extrapolate stream discharge every minute for the 29-day period. This dataset contains the following files: 1. 660_Stage_Data_Downstream_Manual_Corrected; Time series of barometric pressure, water pressure, water level, and interpolated discharge for the study period. 2. Velocity_Data_2019_published; Summary data of velocity and stream geometry measurements collected with the Acoustic Doppler Velocimeter 3. Depth_Velocity_SiteX_Profile_MMDDYYYY; Detailed stream velocity and geometry measurements for each of the 57 site where X is the site number This data is further described in Leidman et al., 2023.
DOI: 10.18739/a2pz51n58
title: Conductivity-Temperature-Depth (CTD) and Geochemistry Data from 2021 Expedition of the Canadian Coast Guard Ship Louis S. St-Laurent

description: Contains data from a hydrographic cruise conducted about the aboard the Canadian Coast Guard Ship, CCGS Louis S. St-Laurent, August 19 to September 16th, 2021 under the Beaufort Gyre Observing System (BGOS)/Joint Ocean Ice Study (JOIS). There were 57 conductivity temperature depth (CTD) casts performed using a SBE911+ CTD system with 24 10-Liter (L) Niskins. The CTD data for down casts are provided in 1-decibar (db) averaged files (*.cnv), in Seabird's text format with one file per cast and separate files. Cruise documentation is available as a text file. Geochemistry data are provided in a separate excel spreadsheet.
DOI: 10.18739/a2q23r20h
title: Beaver pond bathymetry rasters and point depths around the Seward Peninsula, Alaska 2021-2022

description: The Arctic Beaver Observation Network is a 5-year project (2021-2026) funded by the National Science Foundation. The natural science part of the project uses remote sensing to observe the progress and impacts of beaver engineering in the Arctic, starting in Alaska and extending into Canada and Eurasia. The project also establishes field sites at tundra beaver ponds to study the implications of beaver engineering on hydrology and permafrost, as well as pond evolution documented using Unmanned Aerial Systems (UAS). Remote sensing work will map beaver ponds over time. Field measurements at tundra beaver ponds are made in August and late March. Data generated by field measurements include water level and temperature from pressure-transducers, subsurface imaging from ground-penetrating radar, sonar measurements for beaver pond bathymetry, tabular data associated with water quality measurements, and ice thickness and water depth (in winter). Data is also posted from UAS surveys: annual visible and multi-spectral surveys, as well as snow depth.
DOI: 10.18739/a2qb9v69x
title: Chironomid species counts and chironomid-inferred summer temperatures, Lake N14, Greenland (early Holocene and late glacial) (2022)

description: This dataset contains subfossil chironomid (Diptera: Chironomidae) species counts and the corresponding chironomid-inferred summer temperatures from a sediment core recovered from Lake N14 in southern Greenland. The record covers the period from approximately 13,800 to 9,900 years ago (cal BP). These data were generated for the study named below, which should be consulted for details and cited when using these data. Medeiros, A.S., Chipman, M., Francis, D.R., Hamerlik, L., Langdon, P., Puleo, P.J.K., Schellinger, G., Steigleder, R., Walker, I.R., Woodroffe, S., and Axford, Y. 2022. A continent-scale chironomid training set for reconstructing arctic temperatures. Quaternary Science Reviews 294, 107728. DOI 10.1016/j.quascirev.2022.107728.
DOI: 10.18739/a2qf8jm1c
title: Arctic lake transient electromagnetic (TEM) soundings 2016-2017

description: This dataset contains transient electromagnetic (TEM) geophysical soundings acquired on Arctic lakes during spring fieldwork 2016 - 2017. Several additional TEM soundings are included acquired on terrestrial permafrost near lakes (for control) or historic boreholes (for validation). Shallow lakes and ponds may cover up to 40 percent of the land surface in Arctic lowland regions. Many of these water bodies traditionally freeze solid during the winter, preserving sub-lake permafrost and keeping soil carbon stocks immobile at depth. This project examines the extent and dynamics of bedfast and floating ice lakes in relation to hypothesized interactions and feedback with permafrost and climate. Measurements were made using an ABEM WalkTEM with a 1600m^2 transmitter loop, a 200m^2 receiver loop, and a 5m^2 receiver loop, all in a center-nested configuration. Raw data for 86 soundings are provided in the Universal Sounding Format (USF), and results after processing (smooth constraint) with ViewTEM (GuidelineGeo/ABEM/Aarhus Hydrogeopyhsics) inversion software are included as tabular geolocated values. A KML indicating point location of the center of each sounding is also provided.
DOI: 10.18739/a2qn5zc8h
title: Geospatial data about watercraft movements in Alaska freshwater from a statewide survey with watercraft owners in 2018

description: A survey with Alaska's watercraft owners was conducted. This dataset used an online mapping tool to collect identify boat movements across Alaska’s coastlines and river systems. Historically, little research has investigated the extent of boats being used for personal transportation, recreation, and subsistence use across this vast landscape. Consequently, the human pathway of transmitting aquatic invasive species (AIS) by boats has not been quantified. Results from a statewide survey with registered boat owners provide geospatial and statistical information to inform policy response on AIS. Policy implications aimed at preventing the introduction of new AIS and the spread of existing AIS are discussed.
DOI: 10.18739/a2qr4ns0z
title: Dissertation research. Indigenous Land Defence: Emerging Networks of Survival. Wet'suwet'en territory, Northern British Columbia, Canada. 2018-2022.

description: Auto-ethnographic research at land defence encampments on Wet'suwet'en land in Northern British Columbia, Canada. Research included media analysis, historical research, and participant observation from 2018-2022. Indigenous peoples are developing novel social mechanisms to deal with rapid change and emerging conflicts, including land resettlement, language revitalization and traditional skill-building. However, we know little about the processes and contexts from which these strategies arise. This project will use a case study from the Northwest Coast of North America to evaluate how Indigenous communities socially and culturally adapt to conflicts over sovereignty, land use and access. This research aims to document the new social networks that emerge in these contexts and how they contribute to Indigenous resiliency. To understand the opportunities and consequences of emerging networks, this project will (1) document the socio-cultural norms that emerge amidst Indigenous resettlement of traditional territories; (2) identify types of social networks that develop; (3) evaluate connections between these new networks and gender, race, and economic factors. The ultimate objective is to trace community networks and evaluate their impacts on Indigenous resilience, an issue with broad implications for Arctic Indigenous communities.
DOI: 10.18739/a2qv3c526
title: Plant aboveground biomass by functional group for alpine tundra and mountain birch woodlands in northern Finland, 2022.

description: This dataset incudes measurements of plant aboveground biomass for 20 sample sites in alpine tundra and mountain birch woodlands across Lapland in northern Finland. The sample sites were measured during August 2022 and spanned a wide range of upland landscapes across the region. Live tree, shrub, graminoid, forb, lichen, and moss aboveground biomass were measured on five plots at each sample site. Moss and lichen biomass were clipped from 0.2 meter (m) x 0.2 m quadrats, while dwarf shrub (less than 30 centimeter (cm) tall), graminoid, and forb biomass were clipped from 0.5 x 0.5 m quadrats, with samples then oven-dried and weighed. Low to tall shrub and tree biomass were estimated by inventorying live stems typically 4 m x 4 m and 8 m x 8 m subplots, respectively, and then applying allometric models that related stem diameter to dry weight. New allometric models were developed for dwarf birch (Betula nana), willow (Salix spp.), and common juniper (Juniperus communis) by harvesting individual plants, measuring stem diameter and oven-dry weight, and fitting non-linear regression models. This dataset includes (1) site metadata; (2) plant functional type biomass for each plot; (3) raw harvest data; (4) raw inventory data; (5) raw shrub allometry data; and (6) shrub allometry regression coefficients. These data were collected as part of a research project focused on mapping plant aboveground biomass across the Arctic tundra biome.
DOI: 10.18739/a2qz22j60
title: Minute-averaged dimethylsulfide dry air mole fractions measured in the University of Colorado container during the 2019-2020 MOSAiC (Multidisciplinary drifting Observatory for the Study of Arctic Climate) expedition

description: This dataset contains ambient air minute-averaged dimethylsulfide dry air mole fractions measured in the Central Arctic during the Multidisciplinary drifting Observatory for the Study of Arctic Climate (MOSAiC) expedition. The backbone of MOSAiC was the year-round operation of the Research Vessel Polarstern that drifted with the sea ice across the Central Arctic from October 2019 to September 2020. Measurements were performed onboard Polarstern in the University of Colorado sea-laboratory container installed below deck in the forward cargo hold. A ~50 meter (m) long Teflon sampling line was deployed from the container to the bow crane to allow measurements forward of the vessel.
DOI: 10.18739/a2r20rz0b
title: Effects of short-interval disturbances continue to accumulate, overwhelming variability in local resilience, 2018-2022.

description: Increasing rates of short-interval disturbances have the potential to rapidly transform ecosystems via shifts in post-disturbance regeneration. While research has explored compound events in multiple biomes, we know little regarding how local site conditions interact with short-interval disturbances to influence post-disturbance regeneration. Furthermore, questions remain regarding the consequences of continued high frequency events: What happens when emerging new communities are themselves subject to short-interval disturbances? To investigate effects of ongoing short-interval fires on regeneration, we examined post-fire forest regeneration in two locations in interior Alaska. We established 50 plots across a mosaic of fire histories (one, two, or three fires in &lt;70 yr) in an upland and lowland site in interior Alaska. To investigate how shifts in community driven by short-interval fires differ according to local site conditions, we quantified abundance, proportion, and density of conifer and deciduous regeneration in a drier upland site and a wetter lowland site. Both sites were dominated by black spruce prior to burning. In the drier upland site, black spruce (Picea mariana) presence declined sharply after two fires, while paper birch (Betula neoalaskana) became increasingly abundant with each additional fire. In the wetter lowland site, less organic soil was consumed by fire and presence of black spruce persisted through an initial single reburn (two fires), indicating local topography may temporarily buffer reburning impacts. However, after three burns, conifers were effectively eliminated in both upland and lowland stands. Deciduous regeneration differed with site: Birch dominated in upland plots, while willow (Salix spp.) and aspen (Populus tremuloides) dominated in lowlands. These results offer strong empirical evidence of the divergence of boreal successional trajectories from previous historic norms. Furthermore, results from this study demonstrate shifts in post-fire succession in forested ecosystems continue to accumulate with additional short-interval disturbance events, overwhelming the interactive effects of local site conditions.