Aims
This course aims to:
• look at the energy budget controlling Earth’s climate quantitatively to better understand the drivers behind it and the feedback loops that control it
• investigate current climate changes within a long-term planetary context
• outline the climatic evolution of our planet over the last 500 million years with a view to being able to understand and predict future change, and possible mitigations
Content
This course will give you a valuable understanding of the science behind climate change. Climate is the long-term average of weather experienced at a particular site over tens, hundreds, thousands or millions of years. Climate is fundamentally controlled by the balance of energy received and given back by the planet. We will start by taking a quantitative look at Earth’s climate system based on the first principles of the Earth’s energy balance. Energy to Earth is provided from the sun, but how constant is this energy flux and what happens to this energy once it reaches the planet? We will discuss the link between this energy balance and atmospheric temperature, and how this feeds into the conditions we experience at the Earth’s surface. We will look at different climatic drivers such as carbon dioxide in the atmosphere, what timescales these drivers operate over and the feedback loops in place to control these. How has human industrial and agricultural activity affected the energy balance, how can the natural system respond, and over what timescales might balance be restored?
In the second part of the course, we will look at how we use geochemical proxies to learn about climate in the past. There is a unique record of temperature and atmospheric changes hidden in the polar icecaps, whilst the sediments of the deep-sea record climate back through millions of years. Reading these longer-term records, we will gain an insight into how the tiniest changes to our planetary orbit can have a profound effect on our energy budget. We will look at how to estimate atmospheric carbon dioxide levels over the past 500 million years and how this links to the evolution of the biosphere.
Presentation of the course
Interactive lectures, discussion and practical exercises will introduce the concepts, ending with a visit to the Godwin Climate Lab at the University of Cambridge.
Course sessions
1. Lecture and practical exercise: Earth’s Energy balance
Looking at solar energy in from the sun, vs energy loss from the planet.
2. Lecture: Forcings and feedbacks
Timescales for drivers and positive and negative feedback loops
3. Lecture and discussion: Earth’s response to change
A review of how Earth responds to changes in the energy balance equation and an outline
of recent policies for mitigating future change. Group discussion.
4. Lecture and discussion: Climate Proxies and reading the long-term climate record
The records from ice and seafloor sediments. Orbital forcing on 100,000-year time scales. Icehouse and Greenhouse Worlds on million-year timescales.
5. Visit: The Cambridge University Godwin Climate Laboratory
Guided tour of one of the UK’s leading climate research labs
Learning outcomes
You are expected to gain from this series of classroom sessions a greater understanding of the subject and of the core issues and arguments central to the course.
The learning outcomes for this course are:
• to gain a quantitative understanding of climate change, the drivers behind it and the feedback loops that control it
• to be able to understand the current climate changes within a long-term context
• to better understand the climatic evolution of our planet over the last 500 million years
