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  • ABoVE: NDVI Trends across Alaska and Canada from Landsat, 1984-2012

    https://cmr.earthdata.nasa.gov/search/concepts/C2162131333-ORNL_CLOUD.xml
    Description:

    This dataset provides the summer NDVI trend and trend significance for the period 1984-2012 over Alaska and Canada. The NDVI were calculated per-pixel from all available peak-summer 30-m Landsat 5 and 7 surface reflectance data for the period. NDVI time series were assembled for each 30-m land location (i.e., non-water, non-snow), from observations that were unaffected by clouds as indicated by data-quality masks and following additional processing to remove anomalous NDVI values. A simple linear regression via ordinary least squares was applied to the per-pixel NDVI time series. The slope of the regression was taken as the annual NDVI trend (unit NDVI change per year) and is reported in the "trend" data files. A Student's t-test was used to assess the significance of the trend and the per-pixel significance is reported in the "trend_sig" data files. A significant positive slope indicates a greening trend, and a significant negative slope indicates a browning trend.

    Links: Temporal Extent: Spatial Extent:
    Minimum Bounding Rectangle: 41.61 -169.97 80.51 -50.17

    ORNL_CLOUD Short Name: Vegetation_greenness_trend_1576 Version ID: 1 Unique ID: C2162131333-ORNL_CLOUD

  • ABoVE: Peak Greenness for Canadian Boreal Forest from Landsat 5 TM Imagery, 1984-2011

    https://cmr.earthdata.nasa.gov/search/concepts/C2162140027-ORNL_CLOUD.xml
    Description:

    This dataset provides a 28-year time series of peak greenness (NDVI) data derived from Landsat 5 TM imagery over the boreal forest region of Canada. Landsat 5 TM scenes were collected for 46 selected sidelap sites along gradients in climate, tree cover, and disturbance history from 1984 to 2011. Peak-greenness reflectance was computed for 30-m Landsat pixels using the maximum normalized difference vegetation index (NDVI) along with the normalized burn ratio (NBR) during the period between days of the year (DOY) 180 and 204. To facilitate trend analysis at each site, the NDVI and NBR data of the 30-m Landsat pixels were regridded to the coarser MODIS 500-m (463.3-m) spatial scale to reduce the effects of missing data and to enhance the significance of the trend. The regridded NDVI and NBR 28-year time series data at 500-m resolution are provided for each of the 46 sites. Two trend analyses were run on the 500-m resolution data and are reported for each site. Supplemental site metadata are also provided, including the number of valid Landsat pixels, land cover composition, and disturbance history, for each 500-m pixel.

    Links: Temporal Extent: Spatial Extent:
    Minimum Bounding Rectangle: 45.32 -124.47 63.44 -53.91

    ORNL_CLOUD Short Name: Canada_Boreal_Forest_Greenness_1587 Version ID: 1 Unique ID: C2162140027-ORNL_CLOUD

  • ABoVE: Riverbank Erosion and Vegetation Changes, Yukon River Basin, Alaska, 1984-2017

    https://cmr.earthdata.nasa.gov/search/concepts/C2162145546-ORNL_CLOUD.xml
    Description:

    This dataset provides a time series of riverbank erosion and vegetation colonization along reaches of the Yukon River (3 study areas), Tanana and Nenana Rivers (1 area), and Chandalar River (1 area) in interior Alaska over the period 1984-2017. The change data were derived from selected 30-m images from Landsat TM, Landsat ETM+, and Landsat Operational Land Imager (OLI) surface reflectance products. Image classification used the Normalized Differenced Vegetation Index (NDVI) with an NDVI threshold of 0.2 to differentiate vegetated from non-vegetated pixels. Images were assigned to one of seven or eight multiyear intervals, within the 1984-2017 overall range, for each study area. Time intervals vary by study site. Change detection identified shifts from one time interval to the next: changes from vegetated to non-vegetated classes were considered riverbank erosion and changes from non-vegetated to vegetated classes were considered vegetation colonization.

    Links: Temporal Extent: Spatial Extent:
    Minimum Bounding Rectangle: 61.91 -161.46 68.15 -143.3

    ORNL_CLOUD Short Name: Erosion_Vegetation_Yukon_1616 Version ID: 1 Unique ID: C2162145546-ORNL_CLOUD

  • ABoVE: Surface Water Extent, Boreal and Tundra Regions, North America, 1991-2011

    https://cmr.earthdata.nasa.gov/search/concepts/C2162118169-ORNL_CLOUD.xml
    Description:

    This data set provides the location and extent of surface water (open water not including vegetated wetlands) for the entire Boreal and Tundra regions of North America for three epochs, centered on 1991, 2001, and 2011. Each of the products were generated with at least three years of ice-free Landsat imagery. The data are at 30-m resolution and were derived from time series of Landsat 4 and 5 Thematic Mapper (TM) data and Landsat 7 Enhanced Thematic Mapper (ETM+) covering all of Alaska and all provinces of Canada. The overall goal was to generate a map of the nominal extent of water for a given epoch, where nominal is neither the maximum nor the minimum but rather a representative extent for that time period.

    Links: Temporal Extent: Spatial Extent:
    Minimum Bounding Rectangle: 41.7 -177.48 82.37 -53.94

    ORNL_CLOUD Short Name: Decadal_Water_Maps_1324 Version ID: 1.1 Unique ID: C2162118169-ORNL_CLOUD

  • ABoVE: Tree Canopy Cover and Stand Age from Landsat, Boreal Forest Biome, 1984-2020

    https://cmr.earthdata.nasa.gov/search/concepts/C2539841646-ORNL_CLOUD.xml
    Description:

    This dataset contains Landsat-derived locally-calibrated estimates of tree canopy cover (TCC) and forest stand age across global boreal forests from 1984-2020 in Cloud-Optimized GeoTIFF (*.tif) format. These raster data span the circum-hemispheric boreal forest biome between 47 to 73 degrees north at 30 m resolution. Machine learning models calibrated with data from the World Reference System 2 were used to predict TCC from Landsat data at 30-m spatial resolution at annual temporal resolution. Through analysis of TCC time series, forest change estimates of stand age from 1984-2020 were developed. The broad spatial and temporal coverage of these data provide insight into forest and carbon dynamics of the global boreal forest system. Boreal forests store a large proportion of global soil and biomass carbon and have experienced disproportionately high levels of warming over the past century.

    Links: Temporal Extent: Spatial Extent:
    Minimum Bounding Rectangle: 45 -180 73 180

    ORNL_CLOUD Short Name: Boreal_CanopyCover_StandAge_2012 Version ID: 1 Unique ID: C2539841646-ORNL_CLOUD

  • ABoVE: Tundra Plant Functional Type Continuous-Cover, North Slope, Alaska, 2010-2015

    https://cmr.earthdata.nasa.gov/search/concepts/C2143401689-ORNL_CLOUD.xml
    Description:

    This dataset provides predicted continuous-field cover for tundra plant functional types (PFTs), across ~125,000 km2 of Alaska's North Slope at 30-m resolution. The data cover the period 2010-07-01 to 2015-08-31. The data were derived using a random forest data-mining algorithm, predictors derived from Landsat satellite observations (surface reflectance composites for ~15-day periods from May-August), and field vegetation cover and site characterization data spanning bioclimatic and geomorphic gradients. The field vegetation cover was stratified by nine PFTs, plus open water, bare ground and litter, and using the cover metrics total cover (areal cover including the understory) and top cover (uppermost canopy or ground cover), resulting in a total of 19 field cover types. The field data and predictor values at the field sites are also included.

    Links: Temporal Extent: Spatial Extent:
    Minimum Bounding Rectangle: 65.59 -167.48 73.8 -143.98

    ORNL_CLOUD Short Name: AK_Tundra_PFT_FractionalCover_1830 Version ID: 1 Unique ID: C2143401689-ORNL_CLOUD

  • ABoVE: Wetland Type, Slave River and Peace-Athabasca Deltas, Canada, 2007 and 2017

    https://cmr.earthdata.nasa.gov/search/concepts/C2240727799-ORNL_CLOUD.xml
    Description:

    This dataset provides ecosystem-types for the Slave River Delta (SRD) and Peace-Athabasca Delta (PAD), Canada, for the time periods circa 2007 and circa 2017. The image resolution is 12.5 m with 0.2-hectare minimum mapping unit. Included are an 18-class modified Enhanced Wetland Classification (EWC) scheme for wetland, peatland, and upland areas. Classes were derived from a Random Forest classification trained on multi-seasonal moderate-resolution images and synthetic aperture radar (SAR) imagery sourced from aerial and satellite sensors, field data, and calculated indices. Indices included Height Above Nearest Drainage (HAND) and Topographic Position Index (TPI), both derived from a digital elevation model, to differentiate between land cover types. The c. 2007 remote sensing data were comprised of early and late growing season Landsat-5, ERS2, L-Band PALSAR from 2006 to 2010 and growing season Landsat thermal composites. The c. 2017 remote sensing data were comprised of early and late growing season Landsat-8 and L-Band PALSAR-2 from 2017 to 2019, Sentinel-1 June VV and VH mean and standard deviations, and growing season Landsat thermal composites. Elevation indices from multi-resolution TPI and HAND were created from the Japan Aerospace Exploration Agency Advanced Land Observing Satellite 30 m Global Spatial Data Model. Also included are the images used for classification and the classification error matrices for each map and time period. Data are provided in GeoTIFF and GeoPackage file formats.

    Links: Temporal Extent: Spatial Extent:
    Minimum Bounding Rectangle: 57.77 -115.29 61.79 -109.64

    ORNL_CLOUD Short Name: Ecosystem_Map_SRD_PAD_1947 Version ID: 1 Unique ID: C2240727799-ORNL_CLOUD

  • Alaska Tidewater Glacier Terminus Positions, Version 1

    https://cmr.earthdata.nasa.gov/search/concepts/C1386250732-NSIDCV0.xml
    Description:

    This data set contains Alaska tidewater glacier terminus positions digitized from USGS topographic maps and Landsat images.

    Links: Temporal Extent: Spatial Extent:
    Minimum Bounding Rectangle: 56.5 -151 61.5 -132

    NSIDCV0 Short Name: NSIDC-0634 Version ID: 1 Unique ID: C1386250732-NSIDCV0

    This collection does not contain any granules

  • Arctic Alaska Vegetation, Geobotanical, Physiographic Maps, 1993-2005

    https://cmr.earthdata.nasa.gov/search/concepts/C2170968664-ORNL_CLOUD.xml
    Description:

    This data set provides the spatial distributions of vegetation types, geobotanical characteristics, and physiographic features for the Arctic tundra region of Alaska for the period 1993-2005. Specific attributes include dominant vegetation, bioclimate subzones, floristic subprovinces, landscape types, lake coverage, and substrate chemistry. This data set generally includes areas North and West of the forest boundary and excludes areas that have a boreal flora such as the Aleutian Islands and alpine tundra regions south of treeline.

    Links: Temporal Extent: Spatial Extent:
    Minimum Bounding Rectangle: 57.08 -173.05 71.37 -138.54

    ORNL_CLOUD Short Name: Alaska_Arctic_Tundra_Veg_Map_1353 Version ID: 1 Unique ID: C2170968664-ORNL_CLOUD

  • Arctic National Wildlife Refuge (ANWR) Data Base, U.S. Fish and Wildlife Service, Alaska

    https://cmr.earthdata.nasa.gov/search/concepts/C2231553077-CEOS_EXTRA.xml
    Description:

    The Arctic National Wildlife Refuge (ANWR) is the most northern and one of the largest Refuges within America's National Wildlife Refuge System. The Arctic Refuge is managed by the U.S. Fish and Wildlife Service, U.S. Department of the Interior. The USFWS ANWR site contains information and data on wildlife, habitat, and people in the Arctic Refuge. The Refuge is home to more than 160 bird species, 36 kinds of land mammals, nine marine mammal species, and 36 types of fish. The ANWR geological and land surface databases are available from the Alaska Geospatial Data Clearinghouse (AGDC) at "http://agdc.usgs.gov/data/projects/anwr/webhtml/" The data consists of political boundaries and coastlines, land cover and vegetation maps, rivers, streams and wetlands, elevation contours, satellite images (Landsat-MSS and Landsat-TM), surficial geology, and coastal bathymetry as well as Alaska statewide land characterization and geospatial data.

    Links: Temporal Extent: Spatial Extent:
    Minimum Bounding Rectangle: 53 -180 74 -130

    CEOS_EXTRA Short Name: EARTH_LAND_USFWS_AK_Wildlife1 Version ID: Not provided Unique ID: C2231553077-CEOS_EXTRA

    This collection does not contain any granules