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Point Cloud Data	Bulk Download	opentopoID: OTLAS.072022.6344.1
Raster Data	Bulk Download	opentopoID: OTSDEM.072022.6344.1

Collection Overview:

Rising sea levels and an increasing frequency of storm events has put deltas worldwide at risk. However, sediment deposition from fluvial sources can build land in deltas and counteract this modern trend of land loss. Understanding sediment transport and deposition patterns in coastal deltas thus represents a promising approach to maximizing their future survival. This lidar dataset was collected as part of an NCALM Seed grant for Justin Nghiem at the California Institute of Technology to help understand modern coastal sediment accretion rates and spatial patterns in the Wax Lake Delta, LA. The study area is located southwest of Morgan City, LA and covers approximately 53 km².

Note about point classifications: Ground classification was done using a morphological filter in Terrascan and points included in class 2. Bathymetry points classification was done on returns from green laser i.e. channel 3 over the waterbody. Due to the characteristics of the water body (murky water, dark bottom), it cannot be ascertained with 100% certainty that the laser returns from shots of green channel that penetrated the water column, are from the bottom. The lowest returns were classified as the bathymetry points (class 40) as they have the highest probability of representing the water body bottom. All the other green channel points (channel 3) over the water body were classified separately in class 9 as water points. The points over the water surface from the IR laser channels (channel 2 and 3) were classified in class 41 as water surface. Class 1 includes the unclassified points from Channels 1,2 and 3.

Therefore, point classifications are as follows:

• 1: Unclassified - all channels
• 2: Ground - all channels
• 9: Water - from channel 3 (green)
• 40: Bathymetric Points - channel 3 (green)
• 41: Water Surface Points - channel 2 and 3 (IR channels)

Publications associated with this dataset can be found at NCALM's Data Tracking Center

Dataset Acknowledgement: Lidar data acquisition and processing completed by the National Center for Airborne Laser Mapping (NCALM). NCALM funding provided by NSF's Division of Earth Sciences, Instrumentation and Facilities Program. EAR-1830734

Dataset Citation: Nghiem, J. (2022). Sediment Accretion Rates and Spatial Patterns in the Wax Lake Delta, LA 2020. National Center for Airborne Laser Mapping (NCALM). Distributed by OpenTopography. https://doi.org/10.5069/G99W0CP6. Accessed: 2024-12-21       Copied to Clipboard

Use License: CC BY 4.0

Dataset Keywords: delta, sediment, accretion, coastal erosion,deposition

Survey Date: 11/06/2020

Publication Date: 08/08/2022

Data Provider and Roles:
Funder

• National Science Foundation

Collector

• National Center for Airborne Laser Mapping

Principal Investigator

• Justin Nghiem - California Institute of Technology

Total number of points: 1,014,124,485 pts

Area: 52.71 km²

Point Density: 19.24 pts/m²

Classifications:

Class 1 - Unclassified	485,303,881
Class 2 - Ground	133,108,815
Class 9 - Water	119,953,562
Class 40 - Reserved	66,343,036
Class 41 - Reserved	209,415,191

Raster Resolution: 1.0 meter

Coordinate System:
Horizontal: NAD83 (2011) / UTM Zone 15N Meters [EPSG: 6344]
Vertical: NAVD88 (GEOID 18) [EPSG: 5703]

Units: meter

Survey Report: Reports

LAS Validation Data Report: Reports

Tile index in shapefile format: Download

Dataset Extent in GeoJSON format:
Point Cloud: LA20_Nghiem.geojson
Raster: LA20_Nghiem.geojson

Dataset Spatial Bounds: North: 29.520495545525°     South: 29.4505387540085°     East: -91.4031888105067°     West: -91.4988467806656°