CIVL3431 Land Surface Process
Assignment 3 – Sensitivity analysis of rainfall-runoff model – 20%
Figure 1. Bucket model
With the model from Assignment 2, demonstrate the following;
(1) Provide a sensitivity analysis of your preferred parameter set (from assignment 2) by varying each parameter by +/- 10% of its numerical value. Vary each parameter individually and collate (plot in the same figure) the resultant hydrographs to illustrate the effect of each parameter. Produce a table quantifying the change in peak flow as well as total discharge from the full 300 time steps for the changes in parameters.
(2) Use Monte Carlo sampling to sample from specified uniform ranges of each parameter to produce randomly sampled parameter sets. Sample 10000 randomised parameter sets.
a. Create dotty plots for each parameter with efficiency 0. Plot the cumulative distributions for each parameter for the selected dataset.
b. Select the best 100 parameter sets according to the Nash-Sutcliffe efficiency. Plot the cumulative distributions for each parameter for the best 100 parameter set. Calculate the range for the maximum discharge from the top 100 samples as well as the range of total discharge.
Write a brief report (4-6 pages) that explains sensitivity approaches and an interpretation of your results. Which parameters display the most sensitivity?
Due date: Monday 29th October 2018 - 5pm