At last, a comparison of erosive power on the Indus and Yarlung Tsangpo. The She Qu divide is where An Yinn sees evidence of the Yarlung Tsangpo reversing the flow of the Siqunama River and flowing into the Subansiri River. (download full-res image)
A look at Eastern Tibet, including "Hydrosheds" SRTM DEM.
This map shows Tibet/China and the tip of India. Entering from the west is the Yarlung Tsangpo,shown up to the point where it enters India and becomes the Siang before becoming the Brahmaputra. National borders are thin black lines, and the watershed boundaries are medium-weight dark blue. The Yigong (?) River descends from the west and the Parlung Tsangpo descends from the east to form the Po Tsangpo. On it's 38 km journey to the Yarlung Tsangpo Gorge, it is joined by the Lulang River. The green points are glacial dams (from O. Korup) and the four black dots mark the end of dam influence.


Click on the graph to download at screen resolution.
Click here to download high resolution.

With proffix.py version 0.092, we created profiles for 684833 cells of the the Tsangpo/Siang and 1414 tributaries, based on the depressless hydrosheds 3" DEM.

As a point-to-point slope would be too noisy, we defined to slope at each point over the length from the next highest elevation to the next lowest elevation (or to the end of the stream, if that cam first.) Three other versions of slope were calculated, using the the additional constraint of looking at least 500m, 1000m, or 2000m in each direction. The last of these (twice 2000m or 4 km) is the same method of caculating slope in Robl, Silwe,&Hergarten. Three of the four slopes are shown below, both for the entire basin and for the Namche Barwe region. Some of the detail is obscured by the point size.

and here are stream power figures based on those slopes and an eight-year mean TRMM rainfall.

Following are three more version of power (based on the 4-km slope) with different symbology and scaling.







And here is power is kilowatts/meter: