Putting a geopspatial spin on your tourist photos

After driving through what seemed like endless, Oregon pine forest we arrived, in the snow, at a small car park high above shimmering blue water. Once out of the car the natural viewpoint opened widely to the north revealing high, rocky cliffs that encircled a vast lake. A conical, pine-speckled island broke up the lakes’ surface directly in front of us and at that point I think our jaws dropped! Aside from a few tourist brochures and a really cool name, we knew nothing about Crater Lake, Oregon before arriving. It is truly a spectacular destination that completely blew us away! But being short on time with a cranky 18 month old and plenty of snow cover I had to forfeit any rock-scrambling and settle on just a few snaps before we continued on our journey across Oregon. We still had to get to Fossil!

Anyway, that trip was quite a few years ago now, and as is often the case with digital photos, they get backed up to a hard drive then shelved or locked away in the cupboard; or, heaven forbid, stuffed into an old laptop bag with stacks of CD-RW discs free to collect dust in the garage or attic! So recently I dusted off my disc drives to revisit some of these photos and despite being point-and-click for the most part I was surprised how well they jogged my memories. In the back of my mind there is always a fear that these digital photos could be lost forever, and with them much of the experience of overseas travel, so I have decided to begin using them.

The view to Wizard Island from where we parked was one of the best I have seen so it’s no wonder this area was designated National Park in 1902.

Wizard Island
View of Wizard Island and the western Crater Lake caldera wall from the carpark.

Photos are great for transporting you back to a place that may be buried in your subconscious and can rekindle emotional attachments that you may have with a particular time or place. The photos I had from Crater Lake certainly stood out among many others that I took while on a road-trip from San Francisco to Seattle, so what better place to start connecting this experience to the digital world.

As we really only had a small taste of the full Crater Lake spectacle I decided to do some desktop exploration of the caldera and Mount Mazuma, the stratovolcano that had a towering peak prior to collapsing several thousand years ago. What I really want to do is provide anyone who sees this landscape or photo with a perspective beyond that of a standard tourist experience. The image represents a fragment of my experience, but so much more can be demonstrated using freely available software and datasets. So the following forms a link between human observation and Earth Science data, extending our perspectives beyond our field of view (or memory). I think the ability to link geospatial elements with Earth imagery is one of the reasons Google Maps is so successful and why 3-dimensional models are becoming such a popular medium for visualising geographic data and the environment.

Firstly, I decided to find some elevation data that I would be able to use to make a map of the area. Within moments I was downloading an elevation raster dataset from an easily-accessed source. These data would make it easier to truly appreciate the slope and scale of Crater Lake through GIS!

Producing a good looking map of elevation data is easy with free-to-use software like QGIS or Landserf, and an extra dimension can be added to surface maps if bathymetric data is integrated with standard surface data. In the example I have prepared here the Crater Lake’s subsurface reveals a broad lava field around the Wizard Island cinder cone, and surprisingly a second volcanic cone entirely submerged near the northern crater wall. Using functions within Landserf and the 2threejs plugin for QGIS I was able to visualise the stunning topography of the crater in 3D and even superimpose surface data such as satellite imagery and geology.

Crater Lake 10m DEM including bathymetric data. The volcanic cone near the northern caldera margin is completely submerged.
Crater Lake 10m DEM including bathymetric data imaged using Landserf. The volcanic cone near the northern caldera margin is completely submerged.

Of course we knew when we entered Crater Lake National Park that we were driving up the sides a collapsed stratovolcano but by revisiting the area using GIS, I was able to gain a new appreciation for just how vast the lake is and how high the encircling cliffs of the caldera walls are. By creating a profile (e.g. using the Profile Tool plug-in for QGIS) – or simply clicking on the raster with the info tool – the elevation data become quantified. You can see that crater walls tower between 300-500m above the lake surface and depth measurements show that Crater Lake is 592m deep.

So these are tricks you can apply fairly easily to any of those places you’ve visited but not had the opportunity to truly explore. In  many cases, particularly when government organisations like the USGS have had an interest, all you need to do is remember the significant geographic/geologic feature and type it into Google to start gathering data.

One of the greatest joys of traveling is being able to observe the outstanding products of Earth’s processes in the spectacular landscapes across the globe.  Happily, we now have the ability to extend relatively short-lived tourist experiences by giving them a fresh perspective through GIS visualisation and placement into a 3D geospatial environment – and learn more about our planet in the process. After all, the more humans understand about their home planet, the more they might want to protect it.

SW Caldera Wall Carpark Flight_forward_750px_75ms
Southwest caldera rim fly-through created with Qgis2threejs and Gimp using USGS elevation data and Google Satellite imagery.

 

 

 

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