Saturday, February 5, 2011

Democratizing LiDAR - Some Sources for LiDAR Images

LiDAR map of parts of Whatcom, Skagit, San Juan and Island Counties

Although having LiDAR on a computer screen is great, a large paper map gives a bigger picture and is a great conversation starter regarding big picture ideas about northwest Washington's landscape. Paul Pittman of Element Solution gave me this paper LiDAR map. I have spent hours looking at it.

You do not have special programs or computer capacity to get LiDAR images. For one thing you could click on the image above and save it to have your own LiDAR map to explore bare earth images of northwest Washington and develop your own theories about the late stages of the last glacial period. But there are some other sources on line that are not too difficult to figure out:

http://opentopo.sdsc.edu/gridsphere/gridsphere?cid=otgoogleearth This page has KML Files that you can click to download and you will be taken straight to Google Earth to view the images and navigate hours away. This access project is supported by a grant from the National Science Foundation and collaborative efforts to provide broad public access to these images including Google. There are not a lot of images yet available, but the California fault lines are fun to look at and there is a an excellent file of the Yakima River from Ellensburg to south of Yakima.

Entrenched meanders in the Yakima River Canyon south of Ellensburg

Braided Yakima River cutting through Ahtanum Ridge at Union Gap south of Yakima 

http://sjcgis.org/SJCGIS/Welcome.html San Juan County very recently added LiDAR bare earth images to their Polaris property search. A bit clunky but a great resource.

Northwest Orcas Island

A few notes on the Orcas Island image. The faint curving lines are old beach strand lines formed as Orcas Island emerged from below sea level as the area rebounded from the mass of glacial ice approximately 12,000 years ago. The image also shows two rather large landslide areas including the bite on the left portion of the picture. I was aware of some poor stability in that area but until I saw this image had no idea the scale of the feature.

http://pugetsoundlidar.ess.washington.edu/lidardata/pslc_j_idx.html The Puget Sound LiDAR Consortium has an interactive map for viewing LiDAR in Puget Sound. I posted a few images of the Seattle fault zone from the images available from the Consortium site HERE

Finally Jefferson County has provided LiDAR images as well as other excellent maps with their map server http://www.co.jefferson.wa.us/idms/mapserver.shtml. Click critical areas maps and then once you zoom into where you want to look go to the layers and click LiDAR. I work all over Washington State and Jefferson County's map server is one of the best and earliest excellent map search programs. You can even find elevtaions on the map and determine slop gradients. 

Screen shot of Jefferson County's Map Server Program showing the Thorndyke Landslide Complex

2 comments:

Dude Diligence said...

Camp Orkila then is right on top of a landslide area.

Dan McShane said...

You know Orcas Island. Yes, the camp is on the slide. I am not sure of the slide mechanics and any ideas would be a wild guess. The slide has not been previously identified as a far as I know.