Video Lectures on Hydrology

I am collecting here my video lectures on Hydrology (in my broken English). These are mostly part of the two GEOframe Winter School held in 2019 and 2020 and from a Summer School on Landslides made a few years ago. Since video lectures on these topics are uncommon, I think it is useful to index them.  I also invite anyone who has similar contributions to share them. I will be happy to add them to my list here.

Here they are below subdivided by arguments with their companion slides:

Catchments Delineation and Geomorphometry

• The basic theory (YouTube video 2019,YouTube2020)
• The derived quantities (YouTube video 2019,YouTube2020)
• Extracting the hillslope (YouTube Video 2019,YouTube2020)
• A little on some geomorphic laws (YouTube video 2019, YouTube2020)

Data Interpolation with Kriging 

• The Kriging's equations (YouTube2019 - Slides were a little modified for 2020, YouTube2020)
• Variography (YouTube video 2019, YouTubeVideo2020)
• The GEOframe Spatial interpolation Package (SIK) (YouTube2019, YouTube2020)
• Error estimation (leave one out) within SIK (YouTube video 2019, YouTube2020)

Richards equation

• Part I
• Part II
• Part III

Radiation for Hydrologists

• The Sun
• Stefan-Boltzmann law
• From Sun to Earth
• Copying with Earth Surface
• Shortwave absorptions by the atmosphere (YouTube video)
• Considering clouds (YouTube video)
• Shortwave-Terrain geometries (YouTube video)
• Longwave radiation (YouTube video)
• Table of Symbols

Evaporation and Transpiration

• Momentum and water vapor transport in atmosphere (YouTube2020)
• Evaporation as energy flow (YouTube2020)
• Derivation of the simplified energy budget (a là Penman-Monteith after Schymanski and Or) (YouTube2020)
• Simplified relatives of PMSO (YouTube2020)
• Leaf Temperature feedbacks
• Transpiration (YouTube2020)
• Further discussions on resistances and the physiology of plants in this video.
• Evaporation from soil (YouTube2020)
• From leaves to canopies (YouTube2019 Video, YouTube2020)

Hydrological Dynamical Systems  (a.k.a. lumped hydrological rainfall-runoff models) 

• Models in Hydrology
• The GEOframe type of models (YouTube2020)
• Representing the Hydrological Dynamical Systems (YouTube2020)
• The Embedded Reservoir Model (YouTube2020)

Other resources

• Other Videos, that I am providing for my Hydrological Modelling Class are here.
• Video collected by Kevin McGuire (GS) are here.

If you do not want to be just a tourist, you can go deeper and exercise with  Jupyter lab and GEOframe. For the latter, please see the material of the GWS2020. To anyone requesting, I can provide the original slides.

A question a day ... about infiltration

One of my colleagues asked this morning the following:  I would like to insert in my model a module for infiltration and redistribution of water in soil. I obviously was thinking to a simple solution. For instance inspired by the paper by Iverson (2000) on which you work times ago. What do you suggest ?

My 2 C:

among the simplest solution I would use the Philip's one, or just a little more complicate, the analytical solution from D'Odorico et al., 2003. That solution derives from a linearization, and in the case you use variable precipitations, you must convolve the kernel solution with them, as indicated in the paper (the same as in the IUH). 

Increasing the complexity of what you could do, next step would be to numerically solve the Richards 1-D equation, and integrate this solution with a simple solution of the water table movement. For a rigorous derivation see the paper Cordano and Rigon, 2008. The model TRIGRS uses more or less this strategy. 

With Emanuele Cordano I also implemented a model for solving the Boussinesq equation with a rigorous and fast method. This could be a solution for the water table movements after infiltration, if you are not satisfied with steady state solutions (http://abouthydrology.blogspot.com/2012/01/solving-boussinesqs-groundwater.html). This last one does not have yet a module for infiltration.

Other would suggest to use Green-Ampt solutions: but I do not see any advantage to use it with respect with the above ones. Perhaps some gain in speed but certainly no gain in clarity. Obviously the simpler the solution, more the parameters must be considered variables to be calibrated ex-post. The assumptions on which they (the parameters) are assumed constant are, in fact,  not really supported by reality, and made for being able to use analytical solutions. 

P.S. - Many in the past (And in the present) use the Curve Number or SCS method. This is a case of pure mimesis of the behavior of infiltration. However, when calibrated, and in certain conditions, the method "works". I hate solutions that just work, but this in particular works, in my opinion for two  reasons: someway it accounts for soil cover (when we usually say infiltration, in reality we have the coupling of interception,   through-flow and,  eventually, infiltration), and, besides, the introduction of an initial abstraction accounts for the fact that the lateral flow is triggered only when there is a little of water table over the bedrock  (http://abouthydrology.blogspot.com/2011/09/on-relative-role-of-upslope-and.html, and http://abouthydrology.blogspot.com/2012/01/simulated-effect-of-soil-depth-and.html)