Earth Systems Research Center, University of New Hampshire20220101Landsat and LiDAR-Derived Canopy Height Metrics for Connecticut River Region of New Hampshirevector digital dataDurham, New HampshireEarth Systems Research Center, University of New HampshireNone<URL:http://www.granit.unh.edu/data/search?dset=canopyheight_polygons/connecticut_river>This polygon dataset is derived from Landsat reflectance and LiDAR elevation data. The polygon boundaries represent "image objects" that were derived using eCognition image segmentation software. The software groups image pixels into contiguous segments based on spectral reflectance. The attributes for each polygon are then calculated from the LiDAR crown height layer. Attributes include maximum, minimum, and mean elevation above the ground and standard deviation within each polygon. Elevation is in meters. This dataset incorporates Landsat data collected in 2015, 2016, 2017, and 2018. LiDAR data were collected in 2015 and 2016.This dataset combines Landsat reflectance data and LiDAR crown height data in a polygon format. Data represent large portions of New Hampshire, USA.2015090420180719This dataset represents much of New Hampshire, including the entire western portion along the border with Vermont and the Lakes Region.None planned-72.704763-70.92467045.30747042.692447ISO 19115 Topic CategorieselevationenvironmentNoneLiDAR, LandsatNoneUnited States, New England, Northeast, New HampshireNoneUsers must assume responsibility to determine the appropriate use of these data. Because of the nature of the source imagery (30m pixels), it is not recommended that the data be used at scales greater than 1:60,000.These data were developed by NH GRANIT using funding from the New Hampshire Space Grant Consortium.Esri ArcGIS 10.9.0.32739Polygon topology exists.Data are complete for the study area.Earth Systems Research Center2021LiDAR-Derived Normalized Digital Surface Model - NHonLine2011050620180524ground conditionnDSMLiDAR-Derived Normalized Digital Surface Model represents a 2-meter resolution LiDAR-derived normalized Digital Surface Model (nDSM) or
Canopy Height Model (CHM) for New Hampshire. It was derived from a statewide LAS Dataset which comprised 8 separate LiDAR collections that
covered the state as of January, 2020. The LAS Dataset was used as input to the ArcGIS "LAS Dataset to Raster" geoprocessing tool which
converted the LAS first return values to raster values in the output data set. Subsequent processing subtracted the corresponding
"bare earth" surface values to produce estimated feature height. It is recognized that this is a simplistic approach to the challenge of
estimating LiDAR-based first return heights. Users should recognize this and keep it in mind when using the data. This dataset comprises
elevation values from the following years: 2011 2012 2014 2016 2018U.S. Geological Survey20150904Landsat 8 Operational Land Imager dataremote-sensing imageProduct ID: LC08_L1TP_013029_20150904onLine20150904ground conditionOLI1Landsat 8 Operational Land Imager Dataset 1 (OLI1), used as basis for image segmentationU.S. Geological Survey20160922Landsat 8 Operational Land Imager dataremote-sensing imageProduct ID: LC08_L2SP_013030_20160922onLine20160922ground conditionOLI2Landsat 8 Operational Land Imager Dataset 2 (OLI2), used as basis for image segmentationU.S. Geological Survey20180719Landsat 8 Operational Land Imager dataremote-sensing imageProduct ID: LC08_L1TP_012030_20180719onLine20180719ground conditionOLI3Landsat 8 Operational Land Imager Dataset 3 (OLI3), used as basis for image segmentationU.S. Geological Survey20170520Landsat 8 Operational Land Imager dataremote-sensing imageProduct ID: LC08_L2SP_013029_20170520onLine2017052020170520ground conditionOLI4Landsat 8 Operational Land Imager Dataset 4 (OLI4), used as basis for image segmentationArcGIS Pro was used to create a mosaic of OLI1, OLI2, OLI3, and OLI4. Only cloud-free areas of OLI1 were used. Output dataset is refered to
as OLI.OLI1, OLI2, OLI3, OLI420211206OLIEarth Systems Research CenterGRANIT Database ManagerGRANIT Database ManagerphysicalMorse Hall, University of New HampshireDurhamNH03824US(603) 862-1214(603) 862-0188granit@unh.eduThe eCognition software (version 10.1, Trimble, Inc.) was used to generate image objects to depict landscape features based on reflectance
values from the Landsat 8 Operational Land Imager (OLI) and LiDAR derived canopy height measures (nDSM). The eCognition multiresolution
segmentation algorithm was used with the following settings to create the image objects; Scale paramter: 50, Shape: 0.25, and
Compactness: 0.75. Both OLI and nDSM were used as input to the algorithm and carried the same weight values. Processing was constrained to
the area defined by the Connecticut River LiDAR collection. The resulting image objects were subsequently exported to this shapefile.OLI, nDSM20211206Earth Systems Research CenterGRANIT Database ManagerGRANIT Database ManagerphysicalMorse Hall, University of New HampshireDurhamNH03824US(603) 862-1214(603) 862-0188granit@unh.eduVectorGT-polygon composed of chains1213448State Plane Coordinate System 1983New Hampshire0.999967-71.66666742.500000984250.0000000.000000Coordinate pair0.0002080.000208Survey FeetNorth American Datum of 1983GRS 806378137.000000298.257222101ConnecticutRiverObjectsConnecticut River image object polygons.Earth Systems Research CenterFIDInternal feature number.EsriSequential unique whole numbers that are automatically generated.ShapeFeature geometry.EsriCoordinates defining the features.nDSM_MAXMaximum pixel height above ground within the polygon, measure in meters.Earth Systems Research CenterEach value represents a unique elevation.nDSM_MEANMean pixel height above ground within polygon, measured in meters.Earth Systems Research CenterEach value represents a unique elevation.nDSM_MINMinimum pixel height above ground within the polygon, measured in meters.Earth Systems Research CenterEach value represents a unique elevation.nDSM_SDStandard deviation of pixel heights within the polygon, measured in meters.Earth Systems Research CenterEach value represents a unique elevation.Shape_LengFeature geometry.EsriCoordinates defining the features.Shape_AreaArea of feature in internal units squared.EsriPositive real numbers that are automatically generated.Earth Systems Research CenterGRANIT Database ManagerGRANIT Database ManagerphysicalMorse Hall, University of New HampshireDurhamNH03824US(603) 862-1214(603) 862-0188granit@unh.eduDigital data in NH GRANIT represent the efforts of the contributing agencies to record information from the cited source materials. Earth Systems Research Center (CSRC), under contract to the NH Office of State Planning (OSP), and in consultation with cooperating agencies, maintains a continuing program to identify and correct errors in these data. OSP, CSRC, and the cooperating agencies make no claim as to the validity or reliability or to any implied uses of these data.20220118Earth Systems Research CenterGRANIT Database ManagerGRANIT Database ManagerphysicalMorse Hall, University of New HampshireDurhamNH03824US(603) 862-1214(603) 862-0188granit@unh.eduFGDC Content Standard for Digital Geospatial MetadataFGDC-STD-001-1998local time