This 2' gravity density grid for the Principal Hawaiian Islands displays the distribution of about 61,000 terrestrial and marine gravity data held in the National Geodetic Survey gravity data base in July 1996. These data were augmented by gravity data contributions from NGA (former National Imagery and Mapping Agency (former Defence Mapping Agency)) and by satellite altimeter-derived marine gravity anomalies computed by Sandwell and Smith (1996). The values show the number of gravity data contained in a given 2' cell. Additional information is available at http://www.ngs.noaa.gov/GEOID/geoid.html We are particularly grateful to NGA (former National Imagery and Mapping Agency) for their assistance and their data contributions.

The Decade of North American Geology (DNAG) gravity grid values, spaced at 6 km, were used to produce the Gravity Anomaly Map of North America (1987; scale 1:5,000,000). Considerable caution should be exercised when using these gridded data in regions of sparse coverage (for example, deep oceanic areas). The spatial distribution of the original data from which the grid was generated is shown on sheet 5 of the published map. Note: There are no gridded data values for Mexico.

Cloud-free Landsat satellite imagery mosaics of the islands of the main 8 Hawaiian Islands (Hawaii, Maui, Kahoolawe, Lanai, Molokai, Oahu, Kauai and Niihau). Landsat 7 ETM (enhanced thematic mapper) is a polar orbiting 8 band multispectral satellite-borne sensor. The ETM+ instrument provides image data from eight spectral bands. The spatial resolution is 30 meters for the visible and near-infrared (bands 1-5 and 7). Resolution for the panchromatic (band 8) is 15 meters, and the thermal infrared (band 6) is 60 meters. The approximate scene size is 170 x 183 kilometers (106 x 115 miles). A Nadir-looking system, the sensor has provided continuous coverage since July 1999, with a 16-day repeat cycle.The Level 1G product is radiometrically and geometrically corrected (systematic) to the user-specified parameters including output map projection, image orientation, pixel grid-cell size, and resampling kernel. The correction algorithms model the spacecraft and sensor using data generated by onboard computers during imaging. Sensor, focal plane, and detector alignment information provided by the Image Assessment System (IAS) in the Calibration Parameter File (CPF) is also used to improve the overall geometric fidelity. The resulting product is free from distortions related to the sensor (e.g., jitter, view angle effect), satellite (e.g., attitude deviations from nominal), and Earth (e.g., rotation, curvature). Residual error in the systematic L1G product is less than 250 meters (1 sigma) in flat areas at sea level. The systematic L1G correction process does not employ ground control or relief models to attain absolute geodetic accuracy.

This project is a cooperative effort between the National Ocean Service, National Centers for Coastal Ocean Science, Center for Coastal Monitoring and Assessment, the University of Hawaii, BAE Systems Spectral Solutions and Analytical Laboratories of Hawaii, LLC. The goal of the work was to incorporate previously developed mapping methods to produce benthic habitat maps generated by photo interpreting georeferenced IKONOS satellite imagery. These point data were generated to conduct ground validation during map preparation.

The gravity station data (65,164 records) were gathered by various governmental organizations (and academia) using a variety of methods. The data base was received in August, 1993. Principal gravity parameters include Free-air Anomalies and Simple Bouguer Anomalies (no terrain correction applied). The observed gravity values are referenced to the International Gravity Standardization Net 1971 (IGSN 71). The gravity anomaly computation uses the Geodetic Reference System 1967 (GRS 67) theoretical gravity formula. The data are randomly distributed south of 50 degrees South.

The gravity station data (32 records) were gathered by Mr. Seth I. Gutman for AridTech Inc., Denver, Colorado using a Worden Prospector gravity meter. This data base was received in June 1985. Principal gravity parameters include Free-air Anomalies and Simple Bouguer Anomalies (no terrain correction applied). The observed gravity values are referenced to the International Gravity Standardization Net 1971 (IGSN 71). The gravity anomaly computation uses the Geodetic Reference System 1967 (GRS 67) theoretical gravity formula. The data are randomly distributed within the area of central San Bernardino County, California.

This data set contains the 2005 and 2010 classifications of Kauai and can be used to analyze change. This data set utilized utilized 35 full or partial WorldView2 multispectral scenes and the 2005 high-resolution Kauai C-CAP data set, which were analyzed according to the Coastal Change Analysis Program (C-CAP) protocol to determine land cover.

The U.S. Geological Survey (USGS) contracted with Hawaii-based Aerial Surveying, Inc. to collect lidar-derived elevation data over the low-lying areas within the northwestern Hawaiian Islands (NWHI) during the summer of 2010. A separate contract issued to Aerial Surveying, Inc. by the National Oceanic and Atmospheric Administration (NOAA) funded the lidar data processing and elevation data product development phases of the project. Lidar data provide high resolution digital elevation models that are used for many applications, including but not limited to sea level rise modeling, habitat assessments, and tsunami inundation modeling. In April 2011, NOAA Papahanaumokuakea Marine National Monument and NOAA Office for Coastal Management deployed a survey crew to the NWHI to collect high accuracy point data to validate the 2010 lidar data. The survey crew used survey-grade Global Positioning System (GPS) receivers to collect high accuracy elevation points. This metadata covers the information for Lisianki Island. This dataset contains lidar point clouds in LAS 1.2 format, classified in the following ASPRS standards as Class 1: Unclassified, Class 2: Ground, and Class 9: Water. The following are the equipment used to create the lidar data sets. Aircraft: Beechcraft Queen Air Lidar Systems: Riegl 140 and 240 Accuracy statements are based on areas of open terrain, with points classified as ground. The accuracy of each point is expected to meet the vertical accuracy standard, derived products may be less accurate in areas of extreme terrain and dense vegetation due to a lesser number of points defining the ground in these areas. Classified data sets such as this one may have varying posting due to some pulses not reaching the ground. This work was conducted under permit number PMNM-2010-033 as approved by NOAA, the U.S. Fish and Wildlife Service (USFWS), and the State of Hawaii, and acknowledged by Dr. Charles L. Littnan of NOAA's Pacific Islands Fisheries Science Center. Original contact information: Contact Name: Lidar Manager Contact Org: Aerial Surveying Inc. Title: Lidar Manager Phone: (808) 327-9439

This project is a cooperative effort between the National Ocean Service, National Centers for Coastal Ocean Science, Center for Coastal Monitoring and Assessment, the University of Hawaii, BAE Systems Spectral Solutions and Analytical Laboratories of Hawaii, LLC. The goal of the work was to incorporate previously developed mapping methods to produce benthic habitat maps generated by photo interpreting georeferenced IKONOS satellite imagery. These point data were generated to conduct ground validation during map preparation.

This data set contains the 2005 and 2010 classifications of Niihau and can be used to analyze change. This data set utilized utilized 10 full or partial WorldView2 multispectral scenes and the 2005 high-resolution Niihau C-CAP data set, which were analyzed according to the Coastal Change Analysis Program (C-CAP) protocol to determine land cover.