Transcript 7.2_Into to Lidar

REMOTE SENSING
WITH
LIDAR
Brian S. Keiling
Program Head – Forest Management
Dabney S.Lancaster Community College
Class of 2010 - 2011
LIDAR - LIGHT DETECTION AND RANGING
NEAR INFRARED BAND OF THE ELECTROMAGNETIC SPECTRUM
RADAR – RADIO DETECTION AND RANGING
MICROWAVE PORTION OF THE ELECTROMAGNETIC SPECTRUM
LIDAR, LiDAR, LIDaR, lidar and LADAR(laser altimetry).
Light detection and ranging
Laser Imaging, Detection and Ranging
Combining the words light and radar
LIDAR
Active versus Passive Remote Sensing
https://www.e- education.psu.edu/lidar/l1_p3.html
LIDAR TYPES
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Airborne
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Topographic
Bathymeric
Terrestrial
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Mobile
Stationary
LIDAR – AIRBORNE TOPOGRAPHIC
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Active Remote Sensing
method.
Laser pulses are
reflected from objects
on or near the ground.
XYZ data collected.
High density of data
points collected.
http://www.fs.fed.us/pnw/pubs/pnw_gtr768.pdf
BATHYMETRIC LIDAR
• Blue –Green laser that can penetrate water and
provide bottomland terrain modeling.
• Water penetration down to 50 meters but clarity is a
limiting factor.
• Often flown simultaneously with digital cameras and
hyperspectral sensors.
MOBILE MAPPING WITH LIDAR
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Collection of 360 degree field of view
Very accurate and highly precise data collection
Provides detailed streetscape and roadway GIS data
Ability to see where airborne lidar cannot
MOBILE MAPPING STREETSCAPE
Mobile mapping streetscape point
cloud
Finished streetscape from mobile
mapping project
https://www.e-education.psu.edu/lidar/l9_p5.html
STATIONARY
Easter Island Moai
http://trl.trimble.com/docushare/dsweb/Get/Document-421274/
LIDAR RETURNS
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Multiple returns.
First is the highest
object.
Up to five (5) returns
per pulse.
Last is not always the
ground.
http://resources.arcgis.com/en/help/main/1
0.1/index.html#//015w00000041000000
LIDAR ATTRIBUTES
CLASSIFICATION
Classification Value
Classification Type
0
Never Classified
1
Unassigned
2
Ground
3
Low Vegetation
4
Medium Vegetation
5
High Vegetation
6
Building
7
Noise
8
Model Key
9
Water
10
Reserved for ASPRS Definition
11
Reserved for ASPRS Definition
12
Overlap
13–31
Reserved for ASPRS Definition
FILE TYPES
LAS – specification for a point cloud file format
with x,y,z and other attributes.
 ASCII – original format for LIDAR data.
 LAZ – lossless LIDAR Compression.
http://www.laszip.org/
 Data we will use compressed from 164 mb to 29
mb.
 LAS Dataset –LAS storage for use in ArcGIS.
 Convert into TIN, DEM, contours and others.
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USES OF LIDAR
Flooding
 Coastline erosion- changes
 Vegetation
 Forestry
 Improving accuracy and resolution of
basemaps.
 Planning
 Urban Growth
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FIND DATA
Virginia- William and Mary hosts state LIDAR
http://www.wm.edu/as/cga/VALIDAR/index.php
 USGS CLICK: Center for LIDAR Information
Coordination and Knowledge (not compressed!)
http://lidar.cr.usgs.gov/
 LIDAR LINKS for mappers
http://www.lidarbasemaps.org/
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LIDAR AVAILABILITY IN VIRGINIA
NASA – TREE INVENTORY AND GIS
UTILIZING LIDAR FOR TREE ASSESSMENT
Student service learning project.
 VWCC, TNCC and DSLCC
 Tree inventory and analysis as part of a
Geospatial Technology project
 Student participation from both GIS and
Forestry disciplines
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NASA TREE INVENTORY AND GIS
Google Earth Image
Lidar point cloud classified with
elevation of the return.
NASA TREE INVENTORY AND GIS
State Record Sassafras
NASA – TREE INVENTORY
NASA TREE INVENTORY
NASA TREE INVENTORY
Utilizing the point cloud
to provide tree canopy
width measurements
NASA TREE INVENTORY
Utilizing the point
cloud to provide
tree height
measurements
SELECTING MUTIPLE TREES WITH LIDAR
OSO WASHINGTON MUDSLIDE
http://seattletimes.com/ABPub/zoom/html/
2023244527.html
AERIAL VIEW OF SLIDE
http://www.bbc.co.uk/newsround/26731774
LIDAR IMAGERY OF OSO SLIDE
http://www.arcgis.com/home/webmap/viewer.ht
ml?useExisting=1&layers=62a2c2dbb4434b31b
9a3ead595b5a0ae
NASA TREE INVENTORY
Questions?