 So there's one more thing I want to talk about with the Holström diagram, and that is related to the Reynolds number. So we have the Reynolds number as the flow speed, the flow depth, the density of the fluid, and the viscosity of the fluid. And this diagram is for water, liquid water. The same process can happen, work with air and other fluids. So the, but because we're talking about water, the density and viscosity are the same. And we have the flow velocity on our vertical axis here. The turbulence is really important for transporting grains, and the Reynolds number captures that average turbulence. So we have this issue with the flow depth, and as the flow depth increases, the turbulence also increases. Thus the Holström diagram has to assume a specific flow depth, and that's shown right here. So it's a flow depth of one meter. So it assumes L equals one meter. Obviously, flow depths vary a huge amount in natural systems. And so the Holström diagram is good for one particular flow depth. But you could imagine that if the flow speed is, for example, lower, somewhere at one, but your flow depth is significantly larger, there will be more turbulence. And a flow speed at this one meter will transport fine sand, or fine sand will be deposited. You could imagine that if you increase the flow depth enough, maybe very coarse sand could still be transported given that higher turbulence with the deeper flow. So we're just going to use the Holström diagram for this class, but there are also shields diagrams, which are three-dimensional. And so they plot grain size on the x-axis, and then they have flow speed and flow depth as y and z. And so it depends, usually, we keep the flow velocity as z, so the shield diagram matches the Holström diagram, and then do the flow depth in the third dimension. So this is a more complicated relationship, and there have been a lot of really great Zoom experiments to calibrate the shields diagram and the Holström diagram with the flow characteristics. Thanks for watching.