Labs WMT CEM: Difference between revisions

Latest revision as of 18:44, 19 March 2020

Coastal Evolution

The Coastline Evolution Model (CEM) addresses predominately sandy, wave-dominated coastlines on time-scales ranging from years to millenia and on spatial scales ranging from kilometers to hundreds of kilometers. Shoreline evolution results from gradients in wave-driven alongshore sediment transport. The model has been used to represent varying geology underlying a sandy coastline and shoreface in a simplified manner and enables the simulation of coastline evolution when sediment supply from an eroding shoreface may be constrained. CEM also supports the simulation of human manipulations to coastline evolution through beach nourishment or hard structures. To learn more about the models in this lab, specifically the Coastal Evolution Model, CEM, you can download this presentation.

This lab includes experiments to couple the terrestrial and coastal domains. We will be looking at a river supplying sediment to a coastal zone, along which wave-driven longshore transport occurs. We will learn about the effect of incoming wave fields, the effect of sediment supply to the coast, and whether this supply happens through a single delta channel or multiple delta channels. Many deltas are classified as wave-dominated deltas, the Arno Delta in Italy is one example.

This lab will run CEM simulation with Python Modeling Tool (Pymt). If you have never used the Pymt, learn how to use it here. The Pymt allows you to set up simulations and run notebooks.

If you are a faculty at an academic institution, it is possible to work with us to get temporary teaching accounts. Work directly with us by emailing: csdms@colorado.edu

Learning objectives

Skills:

use Pymt to run CEM Model
familiarize with a basic configuration of the CEM Model
make changes to key input parameters
hands-on experience with visualizing output in Python

Topical learning objectives:

generate a wave-dominated delta
explore the influence of wave conditions (e.g., wave height, wave angle) on delta formation
explore the influence of river input on delta formation

Lab Notes

You can launch binder to directly run the Jupyter Notebook for this lab through a web browser.

>> Open a new browser window and open the Pymt read the docs page here

>> You will see that there are several example models. In this lab we will select the Coastline Evolution Model.
>> Click on the 'Launch Binder' box and it will allow you to see this lab as a Jupyter Notebook.
>> You can execute the Jupyter notebook code cells using shift -enter.

References

Ashton, A, A.B. Murray, and O. Arnoult. 2001. Formation of coastline features by large-scale instabilities induced by high-angle waves. Nature 414: 296-300., 10.1038/35104541
Ashton, A.D. and Murray, A.B., 2006. High-angle wave instability and emergent shoreline shapes: 2. Wave climate analysis and comparisons to nature. Journal of Geophysical Research 111. F04012., 10.1029/2005JF000423

More on Model description and code

CEM source code: Look at the files that have *deltas* in their name.
CEM description on CSDMS: Detailed information on the CEM model.

@@ Line 1: / Line 1: @@
 ==Coastal Evolution==
-If you have never used the Web Modeling Tool, learn how to use it [[WMT_tutorial|here]]. You will need an account on the CSDMS supercomputer to submit your job.<br>
+The Coastline Evolution Model (CEM) addresses predominately sandy, wave-dominated coastlines on time-scales ranging from years to millenia and on spatial scales ranging from kilometers to hundreds of kilometers. Shoreline evolution results from gradients in wave-driven alongshore sediment transport. The model has been used to represent varying geology underlying a sandy coastline and shoreface in a simplified manner and enables the simulation of coastline evolution when sediment supply from an eroding shoreface may be constrained. CEM also supports the simulation of human manipulations to coastline evolution through beach nourishment or hard structures. To learn more about the models in this lab, specifically the Coastal Evolution Model, CEM, you can download this [[:File:CoupledAvulsionCEMWMTversion.pptx|presentation]].
-More information on getting an account can be found here [[HPCC_Access|Beach HPCC Access]]<br>
-To learn more about the models in this lab, specifically the Coastal Evolution Model, CEM, you can download this [[:File:CoupledAvulsionCEMWMTversion.pptx|presentation]].
-These experiments couple the terrestrial and coastal domains. we will be looking at a river supplying sediment to a coastal zone, along which wave-driven longshore transport occurs. <br>
+This lab includes experiments to couple the terrestrial and coastal domains. We will be looking at a river supplying sediment to a coastal zone, along which wave-driven longshore transport occurs. We will learn about the effect of incoming wave fields, the effect of sediment supply to the coast, and whether this supply happens through a single delta channel or multiple delta channels. Many deltas are classified as wave-dominated deltas, the Arno Delta in Italy is one example.<br>
-We will learn about the effect of incoming wave fields, the effect of sediment supply to the coast, and whether this supply happens through a single delta channel or multiple delta channels.<br>
-Many deltas are classified as wave-dominated deltas, the Arno Delta in Italy is one example.<br>
 <br>
 [[file:ArnoRiverDelta.png| Arno delta]]
 <br>
->> Open a new browser window and open the Web Modeling Tool [https://csdms.colorado.edu/wmt CSDMS WMT]<br>
+This lab will run CEM simulation with Python Modeling Tool (Pymt). If you have never used the Pymt, learn how to use it [https://pymt.readthedocs.io/en/latest/install.html here]. The Pymt allows you to set up simulations and run notebooks.
->> For this specific exercise we will be running the coupled CEM model.
->> It is easiest to choose to 'Open a Model' and select the CEM+Waves + Avulsion example. <br>
->> This loads CEM as the driver from the Component List, and links it to the Avulsion, Waves and River Components. <br>
-[[File:Open CEM examplev2.png|800px]]
->> CEM will now be active in the WMT. <br>
+If you are a faculty at an academic institution, it is possible to work with us to get temporary teaching accounts. Work directly with us by emailing: csdms@colorado.edu
->> CEM receives sediment from an avulsing river, so that is why it is coupled to the Avulsion component.<br>
->> For simplicity, will use a constant sediment supply and water discharge, this is provided by the component called River. <br>
-Once you have loaded the example with the components coupled together, you can set the parameters for each component by going through the different tabs in the parameter list.
-Once your input is set up, you save the entire configuration. Then, you can run it by hitting the arrow run button. This way you generate a job script that is submitted to Beach-the CSDMS High Performance Computing System.
-Provide your Beach account information (i.e. user name and password) to get the run started. <br>
-The status page allows you to keep track of a simulation. From the status page you can eventually download your output files. <br>
-You can always get to teh staus page by clicking on the More tab.
-<br><br>
-'''Exercise 1: Generate a wave-dominated delta''<br>
+'''Learning objectives'''<br>
->> Run a “base-case” simulation for 6,000 time-steps. The CEM component dictates the simulation duration, so set your run duration there, others are ignored<br>
+Skills:
->> Use a constant high river bedload input of 200 kg/s. Use a modest wave height (1 m, 7 seconds). Run your scenario for a single channel with no avulsion. <br>
+*use Pymt to run CEM Model
->> Scroll down to find the output settings. Specify a number of output files to generate after the simulation.<br>
+*familiarize with a basic configuration of the CEM Model
->> These are netCDF files of sea water depth, surface elevation, and seawater to sediment depth ratio. They take up memory space, so make sure the output interval is set to 100 (every 100 timesteps). <br>
+*make changes to key input parameters
+*hands-on experience with visualizing output in Python
-[[File:CEM_wavecomponenttab.png|600px]]
+Topical learning objectives:
-<br>
+*generate a wave-dominated delta
->> Now run the simulation!<br>
+*explore the influence of wave conditions (e.g., wave height, wave angle) on delta formation
->> Download the output files. Unpack the archive and find the most interesting results under the CEM-subdirectory<br>
+*explore the influence of river input on delta formation
->> Use the netcdf file called: "sea_water_to_sediment_depth_ratio.nc".<br>
->>  You can use Panoply to visualize your results. [http://www.giss.nasa.gov/tools/panoply/ download Panoply here]<br>
-<br>
- Question 1a
- Do you think the values for bedload flux and wave height are realistic? If not, why not? Can you give an example of a
- river or delta system that would be experiencing this influx of bedload and a comparable wave regime?
- Question 1b
- Plot up your results in Panoply. Is the evolved delta planview map reminiscent of a wave-dominated delta?
- Question 1c
- Make a movie of the evolution of the delta system evolving over time. Export the animation as a mov file.
-<br><br>
-'''Exercise 2: Explore the influence of wave regime on delta formation'''<br>
-<br>
-Now we will look at changing the wave conditions. Systematically vary the wave regime: the asymmetry of the incoming wave angle (A) and the highness factor for the incoming waves (U).
-A ranges from 0-1. A >0.5 indicates that the majority of wave energy is approaching from the left where a designation of 1.0 indicates all wave energy approaches from the left. A = 0.5 indicates wave energy approach is evenly distributed between the left and right. A < 0.5 indicates the majority of wave energy is approaching from the right where a designation of 0.0 indicates all wave energy approaches from the right.
-U controls the directional spread of the approaching waves, here split into whether waves approach from angles great than or less than the one which maximized alongshore sediment transport (~ 45 deg). High-angle waves approach with angles greater than 45 degrees and low-angle waves approach more directly onshore.  U< 0.5 indicates wave energy predominately approaching from a low angle, U> 0.5 indicates a predominance of high-angle waves. For scenarios involving delta evolution, values less than 0.5 tend to be more reasonable.
->> design  a matrix of 9 experiments with varying A and U values.
+'''Lab Notes'''
- Question 2a
+You can launch binder to directly run the Jupyter Notebook for this lab through a web browser.
- Plot up your last time step for each of your experiments and describe the different delta shapes.
-<br><br>
-'''Exercise 3: Explore the influence of channel avulsions on delta formation'''<br>
+>> Open a new browser window and open the Pymt read the docs page [https://pymt.readthedocs.io/en/latest/examples.html  here]
-Pick a base-case from your previous experiments (be sure to document your settings).
+[[File:launch_binder_cem.png|400px]]
-Run a simulation where you assign a much higher likelihood of channel switching by changing the standard deviation of avulsion angles.
- Question 3a
+>> You will see that there are several example models.  In this lab we will select the Coastline Evolution Model. <br>
- Can you describe a real-world delta system that would have a single channel and a high switching rate?
+>> Click on the 'Launch Binder' box and it will allow you to see this lab as a Jupyter Notebook.<br>
-  Why does this happen? If yes, add a GoogleEarth image to your notes. Plot up your final time step and describe the
+>> You can execute the Jupyter notebook code cells using shift -enter.
- delta geometry.
- Question 3b
- How does delta progradation change with multiple distributary channels? Run a simulation with 3 distributary channels and
- compare progradation rates to your ‘one-channel’ experiment.
- Make a movie of the evolution of the delta with multiple distributaries evolving with Panoply. Export the movie as a mov for your records.
@@ Line 87: / Line 43: @@
 * Ashton, A, A.B. Murray, and O. Arnoult. 2001. Formation of coastline features by large-scale instabilities induced by high-angle waves. Nature 414: 296-300., 10.1038/35104541
 * Ashton, A.D. and Murray, A.B., 2006. High-angle wave instability and emergent shoreline shapes: 2. Wave climate analysis and comparisons to nature. Journal of Geophysical Research 111. F04012., 10.1029/2005JF000423
-* Slott, J., Murray, A.B., Ashton, A., and Crowley, T., 2006. Coastline responses to changing storm patterns, Geophysical Research Letters, 33, L18404., 10.1029/2006GL027445
-* Valvo, L.M., Murray, A.B., and Ashton, A., 2006. How does underyling geology affect coastline change? An initial modeling investigation. Journal of Geophysical Research, 111. F02025., 10.1029/2005JF000340
+<br>
+'''More on Model description and code'''
+* [https://github.com/csdms/cem-old/tree/mcflugen/add-function-pointers CEM source code]: Look at the files that have *deltas* in their name.
+* [http://csdms.colorado.edu/wiki/Model_help:CEM CEM description on CSDMS]: Detailed information on the CEM model.