Monday, October 29, 2012

Water Track Time-Lapse Videos

As I mentioned in my last post, I'll be studying water tracks this coming field season. Because water tracks are fed by melting ice, they don't always have a lot of water flowing in them (and perhaps none at all at some points in time). That means that one day, we'll be at a site without  any sign of a water track, but then it'll appear later, then disappear again.

In this video, you can see Wormherder Creek appear at the beginning of the summer as melt begins. This is the water track I showed you in my previous post. The video runs from November through December of 2010. The water track is in the bottom third of the picture. You can see that, at the beginning of the video in November, there's only a trace of the water track, but it gets wetter (making the soil become darker) over time.

The time lapse video was put together by one of my collaborators, who positioned a camera and set it to take a photo at regular intervals. When you patch those together in order, you get the time lapse video. So, you also see the movement of the sun, which casts a darker shadow later in the day when the sun is behind the mountains. You can see the change in the weather, with some cloudy days and some sunny days. You can even catch a snow storm towards the end of the video in December!

In the next time lapse video, you can see water tracks appear on the mountain sides above Lake Bonney: They don't show up until later in the video, but they're very noticeable when they do! They'll be on the left side of the screen, and you can watch that downhill movement of water from the melting of ice higher up in the mountain. Remember, the video covers December through January, so it took a while for the water to move that distance. The water moves like an underground stream, but not quite as fast as a surface stream!