Legendary fluvial geomorphologist Reds Wolman once said “Floods come from too much water,” and that’s the phenomenon distilled to its core essence. But this bit of wisdom doesn’t give us much to go on if we want to understand what creates floods or why some areas are more flood-prone than …
As you watched the videos about flow generation mechanisms, one of the things that you should have noticed is that climate and landscape characteristics influence the way water gets to streams. (And the way water gets to streams influences the shape of the hydrograph.) Putting it together Below I go …
[Watershed Hydrology students: You should read the whole thing, but if you want to see the TL;DR version first, scroll way down.] The big picture Now that you’ve learned all about the four different ways to generate streamflow, you might be asking yourself why they matter. Here’s why it matters: …
Infiltration is the act of water moving from the land surface into the soil. Usually, we think about infiltration occurring in response to rainfall, where water is applied over the whole land surface. In that case, infiltration is important because it’s one of the deciding factors in how much rainfall …
Hydraulic conductivity is the term used to describe how easily a fluid moves through a porous medium. In the case of water infiltrating into soils, the fluid is the water and the porous medium is the soil. We often use K to represent hydraulic conductivity when we are writing equations. …
In Watershed Hydrology, we’ve been talking about soil moisture and water potential in relation to evaporation and infiltration. An important concept is the idea of the unsaturated zone, where the pores (or open spaces) in the soil, sediment or rock are not completely filled with water most of the time. …
Evapotranspiration is often said to be the most difficult water balance component to directly measure. When water goes from liquid to vapor, you can’t exactly catch it in a bucket or measure flow in a channel. Last week in class, we used a very simplified version of the weighing lysimeter to …
In Watershed Hydrology class this week, we’ll be conducting student-designed experiments to study the factors affecting evapotranspiration. I had a lot of fun picking out various species of plants today and I’m looking forward to seeing how each group sets up their experiments and what results we get. The procedure …
In the previous post, I reviewed approaches for point measurements of precipitation (i.e., rain gauges), talked about the care that must be taken to site well and minimize undercatch, and identified some of the common data sources for rain gauge measurements in the United States. Rain gauges do a great …
The Watershed Hydrology Lab will be at the Geological Society of America annual meeting in early November. Graduate student Catherine Ruhm will be giving a talk in the session on “Geology and Hydrology of Your Public Lands: Understanding and Managing America’s Geologic Heritage, Active Processes, Geohazards, Energy Development, and Mineral …