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2012 FEMA Topographic Lidar: Hudson-Hoosic and Deerfield Watersheds, Massachusetts

browse graphicThis kmz file shows the extent of coverage for the 2012 FEMA Hudson-Hoosic and Deerfield Watersheds, MA lidar data set.
The Light Detection and Ranging (LiDAR) dataset is a survey of the Hudson-Hoosic and Deerfield project area. The entire survey area for Massachusetts is approximately 690 square miles. The LiDAR point cloud was flown at a nominal post spacing of 2.0 meters for unobscured areas. The LiDAR data and derivative products produced are in compliance with the U.S. Geological Survey National Geospatial Program LiDAR Guidelines and Base Specifications, Version 13-ILMF 2010. The flight lines were acquired by Northrop Grumman, Advanced GEOINT Solutions Operating Unit. Derivative products from the aerial acquisition include: high accuracy multiple return LiDAR data, both raw and separated into several classes, along with hydro flattening breaklines, bare earth DEM tiles, control points, and FGDC compliant XML metadata.

Cite this dataset when used as a source.

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    Distribution Formats
    • LAZ
    Distributor DOC/NOAA/NOS/CSC > Coastal Services Center, National Ocean Service, National Oceanic and Atmospheric Administration, U.S. Department of Commerce
    Point of Contact Federal Emergency Management Agency, Region I
    Documentation links not available.
    Originator
    • DOC/NOAA/NOS/CSC > Coastal Services Center, National Ocean Service, National Oceanic and Atmospheric Administration, U.S. Department of Commerce
    Originator
    • DHS/FEMA > Federal Emergency Management Agency, U.S. Department of Homeland Security
    Publisher
    • DOC/NOAA/NOS/CSC > Coastal Services Center, National Ocean Service, National Oceanic and Atmospheric Administration, U.S. Department of Commerce
    Date(s)
    • publication: 2013-10-01
    Data Presentation Form: Digital image
    Dataset Progress Status Complete
    Data Update Frequency: As needed
    Purpose: The purpose of this project was to produce a high resolution LiDAR data set of approximately 2,895 square miles over the Hudson-Hoosic and Deerfield Watersheds in New York.
    Use Limitations
    • These data depict the elevations at the time of the survey and are only accurate for that time. Users should be aware that temporal changes may have occurred since this data set was collected and some parts of this data may no longer represent actual surface conditions. Users should not use this data for critical applications without a full awareness of its limitations. Any conclusions drawn from analysis of this information are not the responsibility of NOAA or any of its partners. These data are NOT to be used for navigational purposes.
    Time Period: 2012-03-20 2012-04-02 2012-04-06 2012-04-13 2012-04-17 2012-04-29  to  2012-03-21 2012-04-03 2012-04-07 2012-04-14 2012-04-20 2012-04-30
    Spatial Reference System: urn:ogc:def:crs:EPSG::4269 Ellipsoid in Meters
    Spatial Bounding Box Coordinates:
    N: 42.750152
    S: 42.398132
    E: -72.554743
    W: -73.383160
    Spatial Coverage Map:
    Themes
    • Topography/Bathymetry
    • Elevation
    • LiDAR
    • Light Detection and Ranging
    • LAZ
    • Remote Sensing
    Places
    • US
    • Massachusetts
    • Berkshire County
    • Franklin County
    Use Constraints No constraint information available
    Fees Fee information not available.
    Lineage Statement Lineage statement not available.
    Processor
    • DOC/NOAA/NOS/CSC > Coastal Services Center, National Ocean Service, National Oceanic and Atmospheric Administration, U.S. Department of Commerce
    • DOC/NOAA/NESDIS/NGDC > National Geophysical Data Center, NESDIS, NOAA, U.S. Department of Commerce
    Processing Steps
    • The ABGPS, inertial measurement unit (IMU), and raw scans are collected during the LiDAR aerial survey. The ABGPS monitors the xyz position of the sensor and the IMU monitors the orientation. During the aerial survey, laser pulses reflected from features on the ground surface are detected by the receiver optics and collected by the data logger. GPS locations are based on data collected by receivers on the aircraft and base stations on the ground. The ground base stations are placed no more than 40 km radius from the flight survey area.
    • The ABGPS, IMU, and raw scans are integrated using proprietary software developed by Optech and delivered with the Optech System. The resultant file is in a LAS binary file format. The LAS version 1.2 file format can be easily transferred from one file format to another. It is a binary file format that maintains information specific to the LiDAR data (return number, intensity value, xyz, etc.). The resultant points are produced in the NAD83/2007 UTM 18 North Coordinate System, with units in Meters and referenced to the NAVD88 datum. The LiDAR mass points were processed in American Society for Photogrammetry and Remote Sensing LAS 1.2 format. The header file for each dataset is complete as defined by the LAS 1.2 specification. The datasets were divided into a 1500 meter by 1500 meter tiling scheme. The tiles are contiguous, do not overlap, and are suitable for seamless topographic data mosaics that include no "no data" areas. The names of the tiles include numeric column and row designations and all files utilize the LAS file extension.
    • The unedited data are classified to facilitate the application of the appropriate feature extraction filters. A combination of proprietary filters are applied as appropriate for the production of bare earth digital elevation models (DEMs). Interactive editing methods are applied to those areas where it is inappropriate or impossible to use the feature extraction filters, based upon the design criteria and/or limitations of the relevant filters. These same feature extraction filters are used to produce elevation height surfaces.
    • Filtered and edited data are subjected to rigorous QA/QC, according to the Northrop Grumman, Advanced GEOINT Solutions Operating Unit Quality Control Plan and Procedures. A series of quantitative and visual procedures are employed to validate the accuracy and consistency of the filtered and edited data. Ground control is established by Northrop Grumman, Advanced GEOINT Solutions Operating Unit and GPS-derived ground control points (GCPs) in various areas of dominant and prescribed land cover. These points are coded according to land cover, surface material, and ground control suitability. A suitable number of points are selected for calculation of a statistically significant accuracy assessment, as per the requirements of the National Standard for Spatial Data Accuracy. A spatial proximity analysis is used to select edited LiDAR data points within a specified distance of the relevant GCPs. A search radius decision rule is applied with consideration of terrain complexity, cumulative error, and adequate sample size. Accuracy validation and evaluation is accomplished using proprietary software to apply relevant statistical routines for calculation of Root Mean Square Error (RMSE) and the National Standard for Spatial Data Accuracy (NSSDA), according to Federal Geographic Data Committee (FGDC) specifications.
    • The Bare Earth DEM was extracted from the raw LIDAR products and attributed with the bare earth elevation for each cell of the DEM. Bare Earth DEMs do not include buildings, vegetation, bridges or overpass structures in the bare earth model. Where abutments were clearly delineated, this transition occurred at the junction of the bridge and abutment. Where this junction was not clear, the extractor used their best estimate to delineate the separation of ground from elevated bridge surface. In the case of bridges over water bodies, if the abutment was not visible, the junction was biased to the prevailing stream bank so as not to impede the flow of water in a hydrographic model. Bare earth surface includes the top of water bodies not underwater terrain, if visible.
    • The NOAA Coastal Services Center (CSC) received topographic files in LAS V1.2 format. The files contained lidar elevation measurements, intensity values, scan angle values, return information, and GPS week time. The data were received in UTM Zone 18N, NAD83 coordinates and were vertically referenced to NAVD88 using the Geoid09 model. The vertical units of the data were meters. CSC performed the following processing for data storage and Digital Coast provisioning purposes: 1. Points in Class 11 (Unknown) wer changed to Class 14. 2. The topographic las files were converted from orthometric (NAVD88) heights to ellipsoidal heights using Geoid09. 3. The topographic las files were converted from a Projected Coordinate System (UTM Zone 18N) to a Geographic Coordinate System (NAD83). 4. The topographic las files' horizontal units were converted from meters to decimal degrees. 5. The data were converted to LAZ format.
    • The NOAA National Geophysical Data Center (NGDC) received lidar data files via ftp transfer from the NOAA Coastal Services Center. The data are currently being served via NOAA CSC Digital Coast at http://www.csc.noaa.gov/digitalcoast/. The data can be used to re-populate the system. The data are archived in LAS or LAZ format. The LAS format is an industry standard for LiDAR data developed by the American Society of Photogrammetry and Remote Sensing (ASPRS); LAZ is a loseless compressed version of LAS developed by Martin Isenburg (http://www.laszip.org/). The data are exclusively in geographic coordinates (either NAD83 or ITRF94). The data are referenced vertically to the ellipsoid (either GRS80 or ITRF94), allowing for the ability to apply the most up to date geoid model when transforming to orthometric heights.

    Metadata Last Modified: 2013-11-19

    For questions about the information on this page, please email: mike.sutherland@noaa.gov