Using Lidar Elevation Data to Develop a Topobathymetric Digital Elevation Model for Sub-Grid Inundation Modeling at Langley Research Center

Abstract

SummaryThe LaRC GIS Team installed a prototype water level monitoring system on Brick Kiln creek on Langley Research Center property. The purpose of this system is to monitor water level fluctuations to support local tide analysis. The system consists of a pressure sensor (calibrated to read water depth) and a battery-powered datalogger which records data to internal, non-volatile memory. Collected data is uploaded to a PDA or laptop over an on-demand Bluetooth RF connection. Initial data collected over a week correlates well with data from the same period for Sewell's Point (downloaded from NOAA).

Citizen-Science for the Future: Advisory Case Studies From Around the Globe

“…(A) A simple bathtub model using topographic elevations corresponding to current or forecasted water levels at a nearby water level sensor (Loftis et al, 2013(Loftis et al, , 2015. (B) A street-level hydrodynamic model fed atmospheric and open boundary tidal and prevailing ocean current inputs from large scale models translated to the street level via computationally efficient non-linear solvers (Wang et al, 2014) and semi-implicit numerical formulations (Loftis et al, 2016) aided by a sub-grid geometric mesh (Steinhilber et al, 2016) with embedded Lidar data (Boon et al, 2018). (C) Interpolated measurements from densely-populated mesh networks of water level sensors advised by artificial intelligence and real-time data assimilation, such as StormSense .…”

“…With such a disparity of technologies across a monitoring group, a radial accuracy error metric (in m) was recorded for each measurement to inform scientists of a circular envelope of possible user locations for each measurement (Loftis et al, 2016). These locational accuracies are the first filtering metric when reviewing data.…”

Computational grid, subgrid, and pixels

“…Given a staggered grid as defined above, Equations (1)-(2) can be conveniently discretized with the semi-implicit method described in the work of Casulli. 13 This method, which has proved to be quite successful in several applications (see, eg, other works [18][19][20][21][22][23][24][25][26] ), is adapted here to simulate shallow water flows with extreme subgrid resolution such as described by a detailed digital elevation model.…”

“…Several advantages offered by the subgrid approach have been demonstrated in many applications over the last decade (see, eg, other works [18][19][20][21][22][23][24] ). Essentially, equally acceptable numerical results can be produced at much lower computational cost with a coarser computational grid that contains detailed subgrid specifications.…”

Examining the utility of Simultaneous Localisation and Mapping (SLAM) LiDAR on a low-altitude unmanned aerial vehicle (UAV) across environments of various composition and dynamic complexity

“…Primarily interested in temporal changes of the foredune stoss slope and beach surface, the Ground Extractor tool within 3DR was utilised to classify and retain only 'ground-points' and, similar to previous studies [86,88,89,109], create DTMs of the Analysis Area. Here, DTMs were created using a slope setting of 55°, 'local steep slopes' strategy and refined using an average point distance of 0.020m as derived from the observed mean GSD of the Hovermap point clouds ( Fig.…”