Download Climate Change and Climate Modeling

Climate Change and Climate Modeling
Sample Syllabus
Instructor:
T.A.:
Office:
Office:
Phone:
Phone:
email:
email:
Course web page:
Textbook web page: http://www.atmos.ucla.edu/neelin/climatebook
Office hours:
Prof.: To be announced or by appointment.
T.A.: To be announced in discussion section.
Global environment issues involving climate change due to human activities or natural climate
variations are presented for students with a background in the sciences. This course provides a
quantitative introduction to the new science of climate modeling, which attempts to understand
and predict these climate changes. The El Niño phenomenon will be used as a primary example
of natural climate variation for which predictions with climate models are now possible. Global
warming will be the focus for human-induced change.
Recommended Text(s)
Neelin, J. D., Climate Change and Climate Modeling (Cambridge University Press, 2010)
Grading
Problem sets (3) 30% (including parts done in discussion section)
Midterm 30%
Final exam 40%
Prerequisites
This course is intended for students majoring in any science area (including biological sciences).
Some basic calculus and physics preparation is required, but no background in atmospheric
sciences is necessary.
Web-based material on problem sets
Some of the problems sets will include accessing web based material from climate research
groups that is not controlled by the instructor; it is recommended to access this well in advance
of the deadline. Some problem sets will have a problem that can be done as an exercise in
discussion section.
Course Outline
*Sections in [ ] will not be covered or will be abbreviated this year
Note to instructors: for a 10-week (quarter system) course, with lectures of 2h40min/week, a midterm occupying one
lecture, and review sessions 1.5 lectures: certain sections should be abbreviated as in this example, or equivalent.
Chapter 1
Overview of Climate Variability and the Science of Climate Dynamics
• Climate dynamics, climate change and climate prediction
• The chemical and physical climate system
Chemical and physical aspects of the climate system
El Niño and global warming
• Climate models - a brief overview
• Global change in recent history
Trace gas concentrations
A word on the ozone hole
[Some history of global warming studies]
Global temperatures
• El Niño: An example of natural climate variability
[Some history of El Niño studies]
Observations of El Niño: the 1997-98 event
The first El Niño forecast with a coupled ocean-atmosphere model
• Paleoclimate variability
Chapter 2
Basics of Global Climate
• Components and phenomena in the climate system
Time and space scales
Interactions among scales and the parameterization problem
• Basics of radiative forcing
Blackbody Radiation
Solar energy input
• Globally averaged energy budget—first glance
• Gradients of radiative forcing and energy transports by atmosphere and ocean
• Atmospheric circulation
[Vertical structure]
Latitude structure of the circulation
Latitude-longitude dependence of climate features
• Ocean circulation
Latitude-longitude dependence of climate features
The ocean vertical structure
The ocean thermohaline circulation
• Land surface processes
• Carbon cycle
Chapter 3
Physical Processes in the Climate System
• Conservation of momentum
Coriolis force
Pressure gradient force
Velocity equations
Application: geostrophic wind
[Pressure-height relation: Hydrostatic balance]
Application: pressure coordinates
• Equation of state
Equation of state for the atmosphere: Ideal gas law
Equation of state for the ocean:
[Application: height-pressure-temperature relation]
Application: thermal circulations
Application: sea level rise due to oceanic thermal expansion
• Temperature equation
Ocean temperature equation
Temperature equation for air
[Application: the dry adiabatic lapse rate near the surface]
[Application: decay of a sea surface temperature anomaly]
Time derivative following the parcel
• Continuity equation
Oceanic continuity equation
Atmospheric continuity equation
[Application: coastal upwelling]
Application: Equatorial upwelling
Application: Conservation of warm water mass in an idealized layer above the thermocline
• Moisture equation and salinity equation
Conservation of mass applied to moisture
Sources and sinks of moisture, and latent heat
[Conservation of mass applied to salinity]
• Moist processes
Saturation
Saturation in convection; Lifting condensation level
The moist adiabat and lapse rate in convective regions
[Moist convection]
• [Wave processes in the atmosphere and ocean]
[Gravity waves]
[Kelvin waves]
[Rossby waves]
• Overview
Chapter 4
El Niño and Year-to-Year Climate Prediction
• Recap of El Niño basics
The Bjerknes Hypothesis
• Tropical Pacific climatology
• ENSO mechanisms I: Extreme phases
• Pressure gradients in an idealized upper layer
Subsurface temperature anomalies in an idealized upper layer
• Transition into the 1997-98 El Niño
Subsurface temperature measurements
Subsurface temperature anomalies during the onset of El Niño
Subsurface temperature anomalies during the transition to La Niña
• El Niño mechanisms II: Dynamics of transition phases
Equatorial jets and the Kelvin wave
[The Kelvin wave speed]
[What sets the width of the Kelvin wave and equatorial jet?]
Response of the ocean to a wind anomaly
[The delayed oscillator model and the recharge oscillator model]
ENSO transition mechanism in brief
• El Niño prediction
Limits to skill in ENSO forecasts
• El Niño remote impacts: teleconnections
• Other interannual climate phenomena and prospects for seasonal-to- interannual
climate prediction
Hurricane season forecasts
Sahel drought
North Atlantic oscillation and annular modes
Chapter 5
Climate Models
• Constructing a Climate Model
An Atmospheric model
Treatment of sub-grid scale processes
Resolution and computational cost
An ocean model and ocean-atmosphere coupling
Land surface, snow, ice and vegetation
Summary of principal climate model equations
Climate system modeling
• [Numerical representation of atmospheric and oceanic equations]
[Finite-difference versus spectral models]
[Time-stepping and numerical stability]
[Staggered grids and other grids]
[Parallel computer architecture]
• [Parameterization of small scale processes]
[Mixing and surface fluxes]
[Dry convection]
[Moist convection]
Sea ice and snow
• [The hierarchy of climate models]
• Climate simulations and climate drift
• Evaluation of climate model simulations for present day climate
Atmospheric model climatology from specified SST
Climate model simulation of climatology
Simulation of ENSO response
Chapter 6
The Greenhouse Effect and Climate Feedbacks
• The greenhouse effect in Earth’s current climate
Global energy balance
A global-average energy balance model with a one-layer atmosphere
Infrared emissions from a layer
The greenhouse effect: example with a completely IR-absorbing atmosphere
The greenhouse effect in a one-layer atmosphere, global average model
Temperatures from the one-layer energy balance model
• Global warming I: example in the global-average energy balance model
Increases in the basic greenhouse effect
Climate feedback parameter in the one-layer global average model
• Climate feedbacks
Climate feedback parameter
Contributions of various feedbacks to global average temperature response
Climate sensitivity
• The water vapor feedback
• Snow/ice feedback
• Cloud feedbacks
• [Other feedbacks in the physical climate system]
Stratospheric cooling
[Lapse rate feedback]
• [Climate response time in transient climate change]
Transient climate change versus equilibrium response experiments
A doubled-CO2 equilibrium response experiment
The role of the oceans in slowing warming
Climate sensitivity in transient climate change
Chapter 7
Climate Model Scenarios for Global Warming
• Greenhouse gases, aerosols and other climate forcings
Scenarios, forcings and feedbacks
Forcing by sulfate aerosols
Commonly used scenarios
• Global-average response to greenhouse warming scenarios
• Spatial patterns of warming for time-dependent scenarios
Comparing projections of different climate models
Multi-model ensemble averages
Poleward amplification of warming
Summary of spatial patterns of the response
• Climate response time in transient climate change
Transient climate change versus equilibrium response experiments
A doubled-CO2 equilibrium response experiment
The role of the oceans in slowing warming
Climate sensitivity in transient climate change
• Ice, sea level, extreme events
Sea ice and snow
Land ice
Extreme events
• Summary: the best-estimate prognosis
• Climate change observed to date
Temperature trends & natural variability: scale dependence
Is the observed trend consistent with natural variability or anthropogenic forcing?
Sea ice, land ice, ocean heat storage and sea level rise
• Emissions paths and their impacts
• The road ahead