MPhys Physics with Astrophysics / Course details

This course conveys the importance of human energy use and its effects on climate, in the recent past and in the future. It ranges from providing knowledge of detailed understanding and calculation of key physical processes, such as aerosol-cloud feedback mechanisms and greenhouse gas radiative effects, to global scenario assumptions of current and future energy usage combining fundamental knowledge of energy flows in the Earth’s planetary system using examples such as ENSO and thermohaline circulations to population growth dynamics and fossil and renewable energy lifecycles. Students are introduced to simple modelling approaches, and finally to evaluate hypotheses of future energy usage including off-planet energy provision and population migration.

Themes covered will include:

• Introduction to Earth’s Climate – Then & Now
• The state of the atmosphere over the last 800,000 years, past CO2 and greenhosue gas levels, proxies for past temperature.
• The rapidly changing state of the atmosphere since the industrial revolution
• Simple models of radiative transfer, absorption and scattering in the atmosphere by gas molecules and aerosols
• Scattering of radiation by clouds
• Planetary albedo
• The Grey model of the atmosphere
• The global radiative budget and factors that control it
• A simple aerosol model, including single scattering albedo and aerosol optical depth concepts
• Basic cloud processes, cloud optical depth and effective radius, and how these depend on macro and microscale processes
• The Twomey 1^st aerosol-cloud indirect effect, calculations using field observations.
• Why aerosol cloud interactions represent the largest uncertainty in climate models –The CO2 pump handle
• Basic links between the atmosphere and ocean circulations, ENSO El Nino and L Nina – can these be influenced by climate warming?
• Climate Change Evidence - a review of the IPCC Assessment Reports on Climate Change
• Man’s Use of Energy and Population Prediction for the end of the century
• Energy resources & Reserves – Calculating fossil fuel lifetimes
• Alternative Energy Sources – Renewables – can they fill the gap? Implications for society.
• The future of Planet Earth – Geo-engineering approaches – should we do it? – or should we move? – Space habitats and Mars

The aim of this course is to provide students with a deeper understanding of the processes controlling climate. The unit aims to educate students in being able to debate climate change using evidence from the geological and astronomical fields. At the same time the unit aims to deliver more detailed understanding of fundamental atmospheric processes including basic models of radiative transfer and aerosol direct and aerosol-cloud indirect effects and ocean circulation processes. Anthropogenic effects on climate are placed within historical context comparing atmospheric conditions from recent geological and pre-industrial revolution timescales and how these have changed over the past century and a half. Various lines of evidence will be discussed and analysed by comparing both natural climate variability processes, including Milankovitch and Solar Variability cycles, with known greenhouse gas radiative effects.

The second part of the course looks at man’s use of energy, using top down analysis of global energy budgets, how these depend on global population growth, and to estimate what man’s energy needs will be by 2100. The student will understand the various energy sources available from fossil fuels to solar. They will be able to calculate the lifetimes of non-renewable fossil fuel resources, how these will change over the next century, and how the planet must respond to anticipate equitable standards of living for a growing population.

Learning during this course unit builds from one lecture to the next, consisting of 2 lectures per week for 11 weeks over semester 1 (22 hours in total). These provide context and ideas with practical examples needed to complete the 1^1/2 hour final examination. Two hours of student-guided revision lectures are provided together with optional student guided examination problem solving tutorials which will summarize key content from the syllabus.

For effective learning, it is advisable that students attend every lecture and practical class, and revise the previous week's materials between lectures. For Physics students taking this option experience has taught us that one lecture per week together with revision using the on-line podcasts is sufficient to complete the main learning outcomes.

Formative problem-solving questions will be covered in the tutorial lectures for students to work on in their own time and to bring to personal tutorials (optional) if required. The lecturer will be available to provide feedback on these via BlackBoard and personal email.

The answers to questions will be given on BlackBoard and feedback from these will also be placed on BlackBoard to gauge progress in understanding, applying the course content and overcoming any problems using different approaches.

General communication outside of lectures will be via Blackboard announcements and e-mail as required.

The assessment of the course will consist of a 11/2 hour summative exam at the end of Semester 1 with students being required to answer  2 questions from 4, one of which will be a summative-essay question. For postgraduate students requiring units to complete DTP requirements (5 credit option) this will be assessed by an essay requiring additional background reading.

Students are encouraged to utilise the wide variety of learning resources that are available in this subject area. This includes signposting (links) to publicly-available informal contextual resources (e.g. NOAA & NASA videos, Wikipedia, Climate News Articles), directed reading, and podcasts listed on the Blackboard site.

Formative individual feedback on tutorial answers and past examination questions. Further feedback will be provided on the example questions set in lectures. Feedback on exam performance will be provided via a drop-in session early in semester 2 for students to view their marked exam scripts as required.

The course is delivered through 22 standard lectures and 2 tutorial-revision/discussion lectures using past examination problems as examples for problem solving and derivations. Personal or group tutorials are available subsequently on request. Discussion via BlackBoard noticeboard of specific problems and topics is encouraged and anonymysed questions surrounding common problems and concepts highlighted with solutions can be provided by BlackBoard NoticeBoard. Climate change updates using scientific and news websites are provided – both links and summary articles are available via BlackBoard.