Submitted by Anna Pearson (Smith College)
While the other half of our team spent the day out on the coring raft, Team Land spent the day collecting data on the modern lake processes that bring the sediments down into the lake.
Part of our group measured suspended sediment concentration at various points near the delta of the stream between Lake Josephine and Swiftcurrent Lake and between Fishercap Lake and Swiftcurrent. These samples allow us to see how much sediment is moving into Swiftcurrent Lake from both the Grinnell and Swiftcurrent Valleys, respectively. We can then use this information to help us understand the sediment cores from the lake and where that sediment may have come from!
The rest of us measured the water discharge of the stream between Lake Josephine and Swiftcurrent. We did this by measuring water depth at set intervals along the stream, as well as finding water velocity the old-fashioned way– we timed how long it took an orange to float a set distance down the stream! A USGS monitoring station keeps track of how much water leaves Swiftcurrent Lake, so we can combine their data and ours to gain an understanding of how water moves throughout this complex system! I really enjoyed the chance to see how all the different work we’re doing ties together into a more complete picture of the entire glacial lake environment!
Unexpectedly, our discharge measurements were occasionally interrupted by some interested wildlife! We first saw a mama bear and two cubs walk right up next to our equipment. In our initial surprise at their arrival, Didi was forced to climb up out of the river onto the bridge in order to avoid getting too close! Mom and the cubs stayed in the area for most of the day, so we ended up having to wait for awhile and warn hikers that came into the area! It’s been very fun throughout the project to get a chance to communicate all the cool stuff we’re doing with the public all around us since we’re working in a national park, and today was an especially good opportunity to bond with the tourists as we waited out the bears!
Later in the afternoon, we also had to pause our work and get out of the stream after a moose came right by the coring craft and then headed up the stream next to us!