HYDROLOGY AND CLIMATE CHANGE

Knowledge and understanding

The course aims to provide students with fundamental knowledge of hydrology and the hydrological cycle, with particular emphasis on applications in water and environmental engineering under changing climatic conditions.

By the end of the course, students will know and understand:

·       the main components and processes of the hydrological cycle and the effects of human activities on them;

·       the main concepts related to weather, climate and climate change, including the greenhouse effect, emission scenarios and climate projections;

·       the main methods and instruments used for measuring hydrological variables and the principal sources of hydrological information;

·       the principles of watershed and drainage network characterization;

·       the fundamentals of probability theory and statistical analysis applied to hydrological data;

·       the processes governing precipitation, runoff generation and streamflow;

·       the main methods used for flood analysis and rainfall-runoff modelling;

·       the basic concepts related to drought, aridity, desertification and hydrologically driven landslides;

·       the main approaches used to assess the impacts of climate change on the hydrological cycle and hydrological hazards.

Applying knowledge and understanding

By the end of the course, students will be able to:

·       retrieve, process and interpret hydrological data from different sources;

·       apply basic statistical and probabilistic methods to hydrological data;

·       fit probability distributions and assess their goodness of fit;

·       derive and interpret intensity-duration-frequency relationships for extreme precipitation;

·       characterize watersheds and drainage networks using GIS tools;

·       estimate relevant hydrological quantities, including areal precipitation, peak discharge and flood hydrographs;

·       apply basic rainfall-runoff modelling approaches and use hydrological modelling software;

·       interpret climate change scenarios and projections and relate them to possible changes in hydrological processes and hazards;

·       carry out guided hydrological analyses using spreadsheets, GIS software and basic programming tools.

Making judgements

Students will develop the ability to select appropriate data, methods and tools for the analysis of hydrological processes and hydrological hazards.

Through guided applications, they will also develop the ability to critically interpret the results of statistical analyses and hydrological models, assess their assumptions and limitations, and evaluate the possible effects of climate variability and climate change on hydrological processes and extreme events.

Communication skills

Students will acquire the ability to correctly use the technical terminology of hydrology and climate change and to clearly describe hydrological processes, methodologies, data and modelling results.

The guided applications and the discussion of course topics during the final examination will contribute to developing the ability to present and discuss technical results in a clear and rigorous manner.

Learning skills

Students will acquire the methodological tools required to independently explore hydrological problems and the relationships between climate change and the hydrological cycle.

They will also be able to independently consult scientific and technical literature, hydrological and climate data sources, and use computational tools for data processing, spatial analysis and hydrological modelling.

UN 2030 Agenda Goals

The course contributes in particular to the following Sustainable Development Goals (SDGs) of the UN 2030 Agenda:

·       Goal 6: improving water-use efficiency, ensuring sustainable freshwater withdrawals and supply, and protecting and restoring water-related ecosystems;

·       Goal 11: promoting resilient cities and human settlements through integrated climate adaptation and disaster risk reduction strategies;

·       Goal 13: strengthening education, awareness and capacity related to climate change mitigation, adaptation, impact reduction and early warning;

·       Goal 15: combating desertification and land degradation, with particular reference to the effects of drought and floods.

The course includes theoretical lectures, guided applications and educational visits.

The theoretical lectures are aimed at providing the fundamental knowledge of hydrological processes, hydrological measurements and data analysis, watershed characterization, statistical and probabilistic methods in hydrology, rainfall-runoff processes and modelling, hydrological hazards, and the relationships between climate change and the hydrological cycle.

The guided applications are aimed at the practical application of the concepts and methodologies presented during the lectures. They include hydrological data analysis, watershed characterization, statistical and probabilistic analyses, rainfall and flood analysis, and hydrological modelling. Computational tools such as spreadsheets, GIS software and hydrological modelling software may be used during these activities.

Educational visits may also be organized to illustrate practical aspects of hydrological monitoring and the functioning of monitoring systems and nature-based solutions, such as green roofs.

The practical activities contribute to the development of students’ ability to apply the methodologies presented during the course and to critically interpret and discuss the results obtained.

Basic knowledge of Hydraulics is important for understanding hydrological processes, particularly runoff generation and streamflow, and the methods used for their analysis and modelling.

Basic computer skills and familiarity with spreadsheets are also useful for carrying out the guided applications. Basic programming skills, preferably using Matlab, are recommended for some of the practical activities.

Attendance is not mandatory but is strongly recommended, particularly to enable participation in the guided applications and educational visits and to facilitate the acquisition of the practical skills expected from the course.

Attendance is also recommended because non-mandatory intermediate assessment activities may be carried out during the course.

Students who have been granted a special status under University regulations for specific circumstances will agree with the instructor on attendance arrangements and the completion of the guided applications.

1. INTRODUCTION

Course presentation. Development of hydrological science.

2. INTRODUCTION TO THE HYDROLOGICAL CYCLE

Hydrological cycle components. Human effects on the hydrological cycle. Distribution of water resources on Earth.

3. INTRODUCTION TO CLIMATE CHANGE

Climate and weather. Structure of the atmosphere. Earth’s radiation budget. Greenhouse effect. Emission scenarios and simulation of future climate. Climate change adaptation strategies.

4. HYDROLOGICAL INFORMATION

Instruments and methods for measuring hydrological variables. Sources of hydrological information. Hydrological and Hydrographic Services. Radar and satellite observations. Reanalysis data.

5. WATERSHED AND DRAINAGE NETWORK CHARACTERIZATION USING GIS

Watershed delineation. Geomorphological characterization of watersheds. Drainage network characterization. Horton’s and Strahler’s laws.

6. INTRODUCTION TO PROBABILITY THEORY AND STATISTICS

Statistical description of data. Definitions of probability. Probability functions and their properties. Random variables. Cumulative distribution function (CDF) and probability density function (PDF). Discrete and continuous parametric probability distributions. Return period and risk. Distribution fitting and goodness-of-fit assessment. Statistical tests. Regression analysis.

7. PRECIPITATION

Formation of precipitation. Precipitation types. Spatial distribution of precipitation. Estimation of areal precipitation. Frequency analysis of extreme precipitation. Intensity-duration-frequency curves.

8. FLOOD ANALYSIS

Objectives of flood analysis. Formation of runoff and streamflow. Infiltration. Hydrograph components. Rainfall-runoff models. Peak discharge estimation. Design hyetographs. Rational Method. Estimation of time of concentration. Unit Hydrograph. Instantaneous Unit Hydrograph. Conceptual models: time-area, linear reservoir, Nash and Clark models. SCS Unit Hydrograph. Geomorphological Instantaneous Unit Hydrograph (GIUH). HEC-HMS software.

9. SHORT INTRODUCTION TO OTHER HYDROLOGICAL NATURAL HAZARDS

Drought, aridity and desertification. Landslides and their hydrological modelling. Landslide early warning thresholds.

10. IMPACTS OF CLIMATE CHANGE ON THE HYDROLOGICAL CYCLE AND RELATED HAZARDS

Climate change projections from Global and Regional Climate Models (GCMs and RCMs). Hydrological modelling under future climate conditions. Examples of climate change impacts on extreme hydrological hazards.

1. Dingman, S.L., Physical Hydrology, Prentice-Hall, 2002.

2. Maidment, D. (Ed.), Handbook of Hydrology, McGraw-Hill, New York, 1993.

3. Bras, R., Hydrology: An Introduction to Hydrologic Science, Addison-Wesley Publishing Company, Reading, MA, 1990.

4. Peres, D.J., Longo, G., Palazzolo, N., Barbagallo, S., Cancelliere, A. (Eds.), Impatto dei cambiamenti climatici sulla disponibilità e la domanda idrica, Quaderni CSEI Catania, III serie, Vol. 26, Catania, February 2023. SBNPal0359431. [In Italian]

5. Moisello, U., Idrologia tecnica, La Goliardica Pavese, Pavia, 1997. [In Italian]

6. Additional teaching material: handouts, slides and other teaching material distributed during the course and made available through the course’s digital platforms.

The examination is oral and may be taken either in English or in Italian. Students are required to complete the guided applications in order to take the final examination.

Non-mandatory intermediate assessment tests may be carried out during the course.

If intermediate assessments are carried out, the final grade will take into account:

·       the results of the intermediate assessment tests;

·       the quality and methodological correctness of the guided applications;

·       the outcome of the final oral discussion on the course topics.

Alternatively, students may take a single oral examination covering the entire course programme. In this case, the final assessment will also take into account the quality of the guided applications.

The final oral examination is aimed at assessing students’ knowledge and understanding of the course contents, their ability to apply the methodologies covered during the course, their ability to establish connections among hydrological processes, climate change and related hazards, and their ability to correctly use the technical terminology of the discipline.

The final grade will be awarded according to the following criteria:

·       Fail: insufficient knowledge of fundamental topics, significant deficiencies in the ability to apply the methodologies and inadequate use of technical terminology;

·       18–21: sufficient knowledge of the main contents and basic ability to apply the methodologies covered;

·       22–25: satisfactory knowledge of the topics and ability to correctly apply the main methodologies, with satisfactory analytical skills;

·       26–28: good knowledge of the course contents, good analytical and application skills, and appropriate use of technical terminology;

·       29–30: in-depth knowledge, ability to critically integrate the different topics and independently address the problems proposed;

·       30 with honours: excellent and comprehensive knowledge, a high degree of autonomy in applying the methodologies, and excellent analytical, synthesis and communication skills.

Learning assessment may also be carried out online, should circumstances require it.

To ensure equal opportunities and in compliance with current legislation, interested students may request a personal meeting in order to plan any compensatory and/or dispensatory measures based on the learning objectives and their specific needs. Students may also contact the CInAP (Centre for Active and Participatory Integration – Services for Disabilities and/or Specific Learning Disorders) representative within their Department (https://www.cinap.unict.it/content/referenti).

The following is a non-exhaustive list of topics and applications that may be covered in the assessment:

1.     Natural and anthropogenically modified hydrological cycle.

2.     Statistical analysis of hydrological data.

3.     Fitting of probability distributions and goodness-of-fit assessment using graphical and analytical methods.

4.     Precipitation intensity-duration-frequency curves.

5.     Watershed characterization using GIS.

6.     Precipitation measurements.

7.     Streamflow measurements.

8.     Flood hydrograph analysis.

9.     Drought analysis.

10.  Climate change scenarios and projections.