2001 USACE Bathymetric LiDAR: Hawaiian Islands

These data were collected by the SHOALS (Scanning Hydrographic Operational Airborne Lidar Survey) system which consists of an airborne laser transmitter/receiver

capable of measuring 400 soundings per second. The system operates from a deHavilland DHC-6 Twin Otter flying at altitudes between 200 and 400 meters with a

ground speed of about 100 knots. The SHOALS system also includes a ground-based data processing system for calculating acurate horizontal position and water depth.

Lidar is an acronym for LIght Detection And Ranging. The system operates by emitting a pulse of light that travels from an airborne platform to the water surface where a small

portion of the laser energy is backscattered to the airborne receiver. The remaining energy at the water's surface propogates through the water column and reflects off the

sea bottom and back to the airborne detector. The time difference between the surface return and the bottom return corresponds to water depth. The maximum depth

the system is able to sense is related to the complex interaction of radiance of bottom material, incident sun angle and intensity, and the type and quantity of organics

or sediments in the water column. As a rule-of-thumb, the SHOALS system should be capable of sensing bottom to depths equal to two or three times the Secchi depth.

Original contact information:

Contact Org: U.S. Army Corps of Engineers JALBCTX

Phone: 334-690-3467

The purpose of the survey was to collect and map data from the shoreline to -30m depths.

10385

A footprint of this data set may be viewed in Google Earth at:

https://noaa-nos-coastal-lidar-pds.s3.amazonaws.com/laz/mllw/1465/supplemental/hi2001_usace_footprint.kmz

LiDAR points in LAS 1.2 format

none

Any conclusions drawn from the analysis of this information are not the responsibility

of JALBCTX, NOAA, the Office for Coastal Management or its partners.

This data can be obtained on-line at the following URL:

https://coast.noaa.gov/dataviewer/#/lidar/search/where:ID=1465

;

None

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be aware that temporal changes may have occurred since this data set was collected and some parts of this data may no longer represent actual surface conditions.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. These data depict the heights at the time of the survey and are only accurate for that time.

SHOALS has demonstrated capabilities that meet US Army Corps of Engineers Hydrographic Survey accuracy requirements for Class 1 surveys and the International

Hydrographic Organization nautical charting standards for Order 1.

+/- 3 meters (1 sigma); Quantitative Value: 3.0 meters, Test that produced the value: Not tested, compiled to meet value (meters) at 1 sigma (1 standard deviation).

+/- 15 cm (1 sigma); Quantitative Value: 0.15 meters, Test that produced the value: Collected to meet value (meters) at 1 sigma (1 standard deviation)

N/A

N/A