STOCHASTIC HYDROLOGY
(This course will be taught in English)
Department of Bioenvironmental Systems Engineering
Professor
Ke-Sheng Cheng
(Email: rslab@ntu.edu.tw)
Course objectives
  1. To introduce fundamental concept of random variables, random vector and random function, and
    their applications in hydrology.
  2. To demonstrate the stochastic nature of many hydrological variables and processes and how
    hydrological parameters can be estimated by statistical methods.
  3. To discuss the uncertainty involved in stochastic parameter estimation and introduce the techniques
    of stochastic simulation for quantification of uncertainties.
  4. To demonstrate how hydrological processes can be characterized using stochastic models.
Week
Specific topics
Remarks
1
Review of fundamental statistics (I)
  • Random variables and their probability
    density functions
  • Joint and conditional probability
    distributions

STHY0
STHY1
2
Review of fundamental statistics (II)
  • Sampling and sampling distributions
  • Parametric point estimation
  • Parametric interval estimation
  • Properties of estimators
STHY2 , HW1    
3
Stochastic simulation (I) – Univariate
simulation
  • Pseudo random number generation
  • Frequency-factor-based generation
  • Rejection method
STHY3 , HW2
4
Hydrological Frequency Analysis (I)
  • Statistical considerations for data selection
  • Statistical distribution of design storm depth
  • Commonly used distributions
  • General equation for frequency analysis
STHY4 ,
HW3-1
5
Hydrological  Frequency Analysis (II)
  • Test of hypotheses
  • Chi-square GOF test
  • Kolmogorov-Smirnov GOF test
STHY5 , HW4
6
Hydrological Frequency Analysis (III)
  • Moment-ratio-based GOF test
  • L-moment-ratio-diagram
  • Sample size issues and uncertainties of
    sample moments
  • Confidence ellipses for LMRD GOF test
STHY6 , STHY6A,
HW5, MatlabCode
7
Stochastic simulation (II) – Bivariate simulation
  • Bivariate normal distribution
  • Bivariate exponential distribution
  • Bivariate gamma distribution
  • Frequency analysis based on bivariate
    distributions
STHY7 , HW6
8
Introduction to random processes
  • Definition of a stochastic process
  • Characterizing a stochastic process
  • Markovian property
  • Exemplar stochastic processes
STHY8, STHY8_PPT, HW7
HW8 , HW8_AR2.xls
9
Modeling the time variation of storm rainfall
  • Simple scaling model
  • Design storm hyetographs
STHY9 , SSGM_PPT, HW9
SSGM_rainfall_data.xls
computer code
10
Stochastic simulation (III) – Simulation of
random processes
  • Gauss-Markov process
  • Conditional simulation
  • Continuous storm rainfall simulation model
STHY11 , HW9
11
Introduction to Geostatistics
  • Random function
  • Variogram modeling
  • Ordinary kriging
STHY12-1 , STHY12-2
HW10
12
Modeling the spatial variation
  • Contouring design storm depth
  • Raingauge network design
STHY13, PPT file, HW11
13
Hydrological forecasting (I)
  • Time series modeling
  • Time series forecasting
Or
Scaling issues in hydrology
STHY14 , HW12
14
Hydrological forecasting (II)
  • Realtime (adaptive) forecasting – Kalman
    filtering
  • The issue of performance evaluation –
    persistency
STHY15
     
Syllabus
Class announcements:
本課程以英語授課
Course description
Hydrology is a branch of earth science focusing on water-related study. It is also an engineering discipline which
deals with storage, discharge, and utilization of water. Almost all variables involved in hydrological processes
exhibit certain degree of randomness. Either from a scientific or engineering point of view, understanding and
characterizing the random nature of hydrological processes enable us to achieve sound water management
practices.
Stochastic hydrology is the study about characterizing the random nature of hydrological variables and
establishing models that describe the spatial and temporal variations of these hydrological variables. In this
course students will learn step by step from characterizing and simulating a single random variable to simulation
of a random field which is composed of many correlated random variables in space. Stochastic simulation will be
highly emphasized in class since it is the foundation for probability-based risk assessment. Familiarity of
stochastic simulation will open a wide window of potential research and application subjects to students.