The methods for this video are very similar to watershed.ucdavis.edu/doc/recession/time-lapse-hydrography, so start there for a general overview of how we make these videos.
This video differs from the previous versions though in that it represents a combination of a few separate data streams (no pun intended) to get a better picture of the differences between these two rivers. In this video, we include, for the first time, air temperature and water temperature data.
First, some context. The left frames for this video are for the Clavey river and the right frames are from the Tuolumne river at the confluence of the Clavey and Tuolumne rivers. The Tuolumne river is what is referred to as a "regulated" river, meaning that its flow is controlled by an upstream dam. The Clavey river has no dams.
The data for the Clavey came entirely from UC Davis Center for Watershed Sciences loggers that were in the river during this time period. As such, the blue line represents stage (not flow). In the right frame, the flow is approximated from two upstream USGS gages - which could be why the high flow event early on is not completely captured. However, it seems to be generally accurate. As such, this graph represents flow, not stage, and the extent of the flow graph is *not* synchronized with the extent of the Clavey's stage graph.
The air temperature data came from the Clavey logger - so the air temperature is the same and the two graphs are synchronized on extent). The air temperature fluctuates wildly compared to the other variables, and so we used a 24 hour moving average in order to visualize the trend, but less of the extremes (and so you can see the river behind it).
The water temperature data came from two loggers, one in the Clavey river and one in the mainstem Tuolumne. The Tuolumne logger was placed downstream of the confluence, introducing the possibility of influence from the Clavey, but when compared with our data from upstream, it did not differ noticeably.
A few things become apparent now that we have data for both rivers, including temperature:
1) the end of season pulsing from the dam releases on main stem
2) the separation of air temp and water temp in main stem apparent (the Clavey's temperatures roughly track each other in trend and approximate temperature while the mainstem diverges)
3) the early season pulses and significant input from the Clavey could have important ecological role
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