Environmental Geology Lecture 1 -
Introductory comments & foundational material
Geology - the study of the earth from the soil
down. As you will see it is a lot more than identifying minerals and rocks.
exercise: What do you want to learn about in this class, and what is the background you bring to this class?
The photo to the right from the USGS (United States Geological Survey) is of Mount Pinatubo erupting in the Philippines. Such eruptions have obvious local consequences, but can also have regional and global effects. This eruption caused measurable global cooling for a year or so. Understanding volcanism and how it influences human endeavors is one part of environmental geology that will be examined in this course.
Recent environmental geology in the news.
Course goals - what can be gained from this
Some important guiding concepts for the course:
- Scientific Method: Since we are using scientific knowledge
in human affairs it is important to understand the nature of that
knowledge. Two questions may help.
- What is included in the scientific method? One
- Science in the public arena:
- This is an especially important consideration in environmental science and environmental geology, as knowledge is transformed into policy and action.
- Scientific versus political discourse - how do these differ, and how can you distinguish between them?
- The significance of COI - conflict of interest.
- Richard Feyman The uncertainty in science.
- Probabilistic statements and policy - at what point of certainty should one act?
- System diagrams/models and feedback loops:
- Why are system models so crucial in environmental geology? Consider all the factors that influence river behavior and flooding. There are many, and it is quite complex. System models are a rigorous way of dealing with such natural complexity.
- 4 crucial components: reservoirs, inflows and outflows, variables and rules.
- emergent properties: behavior that is not inherent or exhibited by systems components in isolation, but which 'emerge' from their linkage.
- positive versus feedback loops.
- will practice throughout the course.
- very powerful way of analysis that is used in many other endeavors than just earth science where complexity reigns (e.g. in economics). Experience indicates it is not intuitive or familiar and takes distinct effort for most students to learn this way of thinking.
- The diagram to the left was constructed using a system modeling software program known as Stella. It links two different reservoirs (depicted by boxes), a population and a resource that the population depends on. This diagram represents fan initial simple model of how a population can depend on a resource. The population could be people on an island, and the resource could be a crucial nearby fishery. The birth rate spigot icon is an inflow, and the death rate icon is an outflow. For the resource there is a general inflow input process, and then an outflow that is the use that depletes the resource (e.g. fishing). The red arrows show variables that influence an inflow or outflow. The per capita use rate (circle icon) would be a variable that influences the outflow. The population is also a variable for the use outflow (the quantity in one reservoir can be a variable that influences the outflow or an inflow for another reservoir). Note the linkage between resource and death rate. This could reflect starvation effects if not enough resource is available. You could attach a rule to these components that might be along the following lines - each person needs one fish a day in order to survive and if the resource falls beneath this level the death rate increases by a certain percentage. You can probably think of other components to add to this diagram for a better model of an island population depending on a local fishery. What happens for reasonable rules for such a system is that the population reaches an equilibrium level that is controlled by the resource input, but more complex and realistic models show more complicated possibilities.
- Sustainability (the new component).
- definition: living presently in a way that does not compromise the ability of future generations to have a similar quality of life.
- basically a ethical/moral stance.
- long term perspective a crucial component. How long? Five generations a conventional perspective.
- what are some present-day examples of sustainable behavior, and some examples of unsustainable behavior?
In environment geology ethics and morality
intertwine with science. Basic
questions confronting people?
A major challenge in geology and earth science - how do we understand
complex natural systems such as a river system, or a sandy coast
line? First - think of all the factors that determine how a river looks and behaves. This should help you understand what we mean by complex natural system. Then consider how we might pedict future river behavior. Possibilities.
This is a computer generated image of the topography west of Omaha and is an example of scientific visulization. The type of visualization is known as a shaded relief map where the darker the lower the elevation. The dark, curved band to the east is a flood plain associated with the Platte River. One element this image clearly shows is the drainage in the area, the small streams that feed larger streams that feed into the Platte River. What additional history can you infer from this image? What are the factors that influence this history? Often in scientific works the images, the maps and graphs and photographs, carry a good bit of the information, are a point of focus my the reader. Scientific visualization is a very important tool, and a lot of information and good questions can be drawn from an image. The National Science Foundation has a scientific visualization competition (https://www.nsf.gov/news/special_reports/scivis/), demonstrating the value placed in this endeavor.
View along Trans-Canada Highway north of Banff. Five of the various spheres are represented in this picture. Can you describe what element in the photo represents what sphere? Can you also think of links between the various components? By the end of this course you will see and understand these types of relationships even better.
One organizational approach to the various environmental geology topics we will cover is as follows:
- what are the related concerns as demonstrated by examples?
- what is the underlying science, the earth system dynamics that produce the concerns?
- how predictable are the concerns in frequency, specific time, place?
- what can be done to prevent and/or mitigate the undesired consequences?
How to "read" scientific literature? The basic idea is that you read different types of literature differently and one most effectively reads science very different from fiction.
How to use your time in this course in an efficient manner?
Suggested reading (if you like to read): John McPhee, 1989,
The Control of Nature; Farrar, Straus, Giroux Press, N. Y., 272
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