81754 - Climatology

Learning outcomes

Upon successful completion of this course, the student: - knows the basics of physical climatology; - knows the main statistical methods used in climate analysis; - can use the results of both numerical global climate simulations and regional climate models for future climate scenarios evaluation; - acquires abilities in communication on the subject and becomes familiar with the terminology used in climatology; - knows how to use scientific literature.

Course contents

 

The course is organized in two modules delivered by two instructors run in parallel (2+2 hours of each module per week)

Modulo 1: Erika Brattich

Modulo 2: Paolo Ruggieri

Module 1

Climate feedback (F) and sensitivity (S)

• Climate feedback and sensitivity: definition and mathematical derivation

• Feedback mechanisms

• Examples of climate feedback

• Calculations of F and S due to: Change of S0 by 1%; Change of 1% in planetary albedo; Change of 1% in greenhouse parameter; Stefan Boltzmann feedback; Water vapour feedback; Ice albedo feedback; Cloud feedback.

Climate energy balance models

• Zero-dimensional energy balance model

• One dimensional Energy Balance Model

• Zero dimensional-2 layers model

• The biogeochemical feedback: the Daisy-world model

Aerosol and climate

• Aerosol distribution

• Volcanic Eruptions and Stratospheric Aerosols

• Anthropogenic Aerosols and Atmospheric Sulfur

Geochemical cycles

• Early evolution of the atmosphere

• The nitrogen cycle

• the oxygen cycle

• the carbon cycle

• rate of storage and removal of gases in the atmosphere

The Orbital Parameter Theory of Ice Ages

• Historical introduction

• Eccentricity and the Sun-Earth distance

• Obliquity and insolation

• The variation of annual mean insolation

• Orbital parameter evolution

• Testing the theory

• The middle pleistocene transition

IPCC radiative forcings

The Problem of the Data Quality in Climatology

• The importance of data quality in climatology

• The example of ground-based stations

• Data error sources (instruments change, instrument and station relocation, solar radiation sheltering, in situ changes, observation rules changes)

• The metadata

• Some homogenization techniques

Statistics in climatology

• Review of basic probability concepts

• Hypothesis testing: the elements of any hypothesis tests, test levels and p values, one-sided vs. two-sided tests, confidence intervals, error types

• Parametric and non-parametric hypothesis testing

• Principal Component Analysis/Empirical Orthogonal Functions (PCA/EOF)
  

• Extreme Events Theory

 

Module 2

The Global Energy Balance

• The nature of electromagnetic radiation
  
• Emission temperature of a planet and greenhouse effect
• Radiative-Convective Equilibrium
• Surface energy balance
  

The Hydrological Cycle

• Terrestrial branch and atmospheric branch of the hydrologic cycle
  
• The concept of evapotranspiration

Conservation laws and general circulation

• Primitive equations
• Conservation of angular momentum, energy and momentum transport
  

General Circulation of the Atmosphere: Tropics

• Observations
• Held-Hou model and exercises
  

General Circulation of the Atmosphere: Extra-Tropics

• Observations
• Balance of the extra-tropical circulation and exercises

The stratosphere

• Observations
• The Brewer-Dobson circulation and the Ozone Hole
  

The ocean

• The role of the Ocean climate
• Ocean circulation

Climate variability

• El Nino Southern Oscillation and exercises
• North Atlantic Oscillation and exercises
• Climate Change

 

Readings/Bibliography

Lecture notes and slides

Dennis L. Hartmann: Global Physical Climatology ; Academic Press, (2015). 2nd edition, ISBN: 978-0123285317

Introduction to Circulating atmospheres, Ian James Cambridge University Press (1994)

Wilks D. S.: Statistical Methods in the Atmospheric Sciences, 3rd Edition (2011)

Teaching methods

Frontal lectures

Assessment methods

The final exam is inteded to verify the understanding/comprehension of all phenomenological, mathematical/statistical aspects of the topics dealt during the two modules.

The final exam consist in an oral examination during which the student will be asked generally three questions selected between the two modules.

The exam lasts 45 minutes on average.

Teaching tools

PC and Projector

Office hours

See the website of Paolo Ruggieri

See the website of Erika Brattich