Ashford University Environmental Geology Questions -How is the (somewhat cyclic) range

HW.9: Climate

For HW this week, we’re focusing on natural forcings of climate change. Part 1 describes how Milankovitch cycles drive long-term climate change. In Part 2, you can explore the ‘heating’ effect of each Milankovitch component, as well as some hypothetical variations of them. In Part 3, we’ll look at how observed warming differs from these natural cycles.

Part 1: PBS Eons video

Watch this video: “The History of Climate Cycles (and the Woolly Rhino) Explained”.

1.            How is the (somewhat cyclic) range of the wooly rhino like a proxy for climate changes?

2.            Milankovitch describes three geometry changes (tilt, precession, and eccentricity). Which one is attributed to the 41,000 ice age cycle?

3.            What did they find at the John Day Fossil Beds in Oregon that provided evidence for this cycle?

4.            Why do precession and tilt change over long time-scales?

5.            What is responsible for shifting the ice age cycle from 41,000 years to 100,000 years (and also, isn’t this amazing)?

Part 2: Modify Milankovitch cycles

This website allows you to explore different aspects of Earth-Sun geometry. When you open the page, it’s showing present day orbital parameters.

6.            Go through the steps for “Eccentricity”, “Precession”, and “Tilt” that are described at the bottom of the page. Isolating each of these components, and seeing the temperature change (purple graph) over time really helps to understand each one better. Now click “Vostok Ice Core”. Which combination of orbital parameters do you think produces the best match with temperatures derived from the Vostok Ice Core?

7.            If global temperature were only controlled by orbital parameters, how would you expect global temperature to change in the future?

8.            This little interactive is useful in parsing out the drivers of recent climate warming. Anything surprise you here?

Part 3: Climate myths

9.            There are so many climate myths, and Skeptical Science has curated a bunch of them for us. Choose one and describe why it’s a myth, what the science says, and why you think it gained traction. I find this list more useful to read when it’s sorted “by taxonomy”.

Part 4: Reflection

10.          In the U.S., air pollution regulation has been quite successful at driving down trends in a number of key pollutants. Why don't you think the same can be said for CO2 and climate change? (A paragraph or two)