The NOAA Maine Topbathymetric Lidar was collected by NV5 using Leica Chiroptera Hawkeye 4X systems. The lidar acquisitions were flown between 20221006 and 20231216 in 120 missions. The dataset includes topobathymetric data in a LAS format 1.4, point data record format 6. See the 'Lineage' section for detailed classification scheme. This dataset also includes lidar intensity values, number of returns, return number, time, and scan angle. After the initial data submission, NOAA reviewed the data. NV5 corrected the feedback edits and incorporated them into the dataset delivery. Additionally, green laser intensity values were normalized for depth for the dataset resulting in a full redelivery of all LAS files. Finally, a set of normalized intensity rasters was also provided, and can be found at the Bulk Download link.

These data were collected by Dewberry using a CZMIL Super Nova system. The data were acquired from 20220719 through 20220816. The data are rasterized topobathy lidar elevations at a 1 m grid spacing. This dataset consists of approximately 219 square miles of data along the shores of Green Bay and contains 2,630 500 m x 500 m GeoTiff files. In addition to these bare earth Digital Elevation Model (DEM) data, the lidar point data that these DEM data were created from are also available from the NOAA Digital Coast. A link to these data are provided in the URL section of this metadata record.

This data was collected by Woolpert using a Leica Hawkeye4X system. The data were acquired from from November 3, 2022 through Feburary 5, 2023. The data includes topobathy 1m gridded DEM data generated from classes ground (2), bathymetric point (40) and submerged object (43) in the classified point cloud, in accordance with project specifications. The project consists of approximately 3251 square kilometers of data along the Chesapeake Bay coastline. This dataset contains 5000m x 5000m topobathy 1m DEM tiles.

This data was collected by Woolpert using a Leica Hawkeye4X system. The data were acquired from from November 3, 2022 through Feburary 5, 2023. The data includes topobathy 1m gridded DEM data generated from classes ground (2), bathymetric point (40) and submerged object (43) in the classified point cloud, in accordance with project specifications. The project consists of approximately 3251 square kilometers of data along the Chesapeake Bay coastline. This dataset contains 5000m x 5000m topobathy 1m DEM tiles.

This data was collected by Woolpert using a Leica Hawkeye4X system. The data were acquired from from November 3, 2022 through March 5, 2023. The data includes topobathy 1m gridded DEM data generated from classes ground (2) and bathymetric point (40) in the classified point cloud, in accordance with project specifications. The project consists of approximately 3251 square kilometers of data along the Chesapeake Bay coastline. This dataset contains 5000m x 5000m topobathy 1m DEM tiles.

Woolpert, Inc. was contracted to acquire and process topographic-bathymetric lidar for the islands of Anatahan, Alamagan, Guguan, and Sarigan in response to Hurricane Yutu for Quantum Spatial, Inc. (QSI). Woolpert collected lidar using their Leica HawkEye 4X (HE4X) topo-bathy lidar sensor that consists of a Chiroptera 4X (CH4X) sensor, with an additional Leica 40kHz deep bathymetric channel to provide high density topo lidar. The HE4X is a latest generation topographic and bathymetric lidar sensor. The system provides denser data than previous traditional bathymetric lidar systems. It is unique in its ability to acquire bathymetric lidar, topographic lidar and 4-band digital camera imagery simultaneously. The HE4X provided 300 kHz topographic data, an effective 140 kHz shallow bathymetric data and 40 kHz deep bathymetric data. 4-band 80 MP digital camera imagery was also collected simultaneously with the sensor’s RCD-30 camera. The bathymetric and topographic lasers are independent and do not share an optical chain or receivers, so they are optimized for their specific function. As with any bathymetric lidar, maximum depth penetration is a function of water clarity and seabed reflectivity. The HE4X is designed to penetrate to 3 times the secchi depth. This is also represented as Dmax = 4/K, where K is the diffuse attenuation coefficient, and assuming K is between 0.1 and 0.3, a normal sea state and 15% seabed reflectance. Both the topographic and bathymetric sub-systems use a palmer scanner to produce an elliptical scan pattern of laser points with a degree of incidence ranging from +/-14 degrees (front and back) to +/-20 degrees (sides), providing a 40 degrees field of view. This has the benefit of providing multiple look angles on a single pass and helps to eliminate shadowing effects. This can be of particular use in urban areas, where all sides of a building are illuminated, or for bathymetric features such as the sides of narrow water channels or features on the seafloor such as smaller objects and wrecks. It also assists with penetration in the surf zone where the back scan passes the same ground location a couple of seconds after the front scan, allowing the areas of whitewater to shift. All topo lidar data for this project were collected simultaneous to meet United States Geological Survey, Quality Level 1 (USGS QL1) with a minimum of 8 pts per square meter at an accuracy of 10cm RMSEz. A minimum of 2 points per square meter were acquired for bathymetric lidar data. For practical purposes the survey area was divided into survey blocks in each island, allowing acquisition to be conducted in the most efficient and consistent manner possible. The data includes topobathy data in an LAS 1.4 format file along with associated bare earth digital elevation models (DEM). This file is the project specified 1 meter bare earth DEM dataset. The dataset was derived from topobathymetric data in a LAS format 1.4, point data record format 6, with the following classifications in accordance with project specifications and the American Society for Photogrammetry and Remote Sensing (ASPRS) classification standards: 1 - unclassified 2 - ground 7 - noise 40 - bathymetric bottom or submerged topography 41 - water surface 42 - derived water surface 43 - manmade submerged feature 45 - water column 1 Overlap - edge clip 1 Withheld - bathy land User data values differentiates between NIR and green lasers. A value of of 1 indicates the point is from the NIR laser, and a values of 2-5 indicate the green laser. This dataset is the 1m orthometric NAVD88 (using Geoid12b) DEM.

These data were collected by Woolpert using a Leica Hawkeye4X system. The data were acquired from from November 3, 2022 through February 5, 2023. The data includes topobathy data in an LAS 1.4 format file classified as unclassified (1), ground (2), low noise (7), topo water surface (9), high noise (18), bathymetric point (40), bathymetric water surface (41), synthetic derived water surface (42), and submerged object (43), in accordance with the American Society for Photogrammetry and Remote Sensing (ASPRS) classification standards.

These data were collected by Woolpert using a Leica Hawkeye4X system. The data were acquired from from November 3, 2022 through February 5, 2023. The data includes topobathy data in an LAS 1.4 format file classified as unclassified (1), ground (2), low noise (7), topo water surface (9), high noise (18), bathymetric point (40), bathymetric water surface (41), synthetic derived water surface (42), and submerged object (43), in accordance with the American Society for Photogrammetry and Remote Sensing (ASPRS) classification standards.

These data were collected by Woolpert using a Leica Hawkeye4X system. The data were acquired from from November 3, 2022 through March 5, 2023. The data includes topobathy data in an LAS 1.4 format file classified as unclassified (1), ground (2), low noise (7), topo water surface (9), high noise (18), bathymetric point (40), bathymetric water surface (41), synthetic derived water surface (42), and submerged object (43), in accordance with the American Society for Photogrammetry and Remote Sensing (ASPRS) classification standards.

These data were collected by Woolpert using a Leica Hawkeye4X system. The data were acquired from from November 3, 2022 through March 5, 2023. The data includes topobathy data in an LAS 1.4 format file classified as unclassified (1), ground (2), low noise (7), topo water surface (9), high noise (18), bathymetric point (40), bathymetric water surface (41), synthetic derived water surface (42), and submerged object (43), in accordance with the American Society for Photogrammetry and Remote Sensing (ASPRS) classification standards.