Overview
As we wrap up our study of the Nile River, and move on to the Sahara Desert and the Sahel, we focus on a few themes that tie these regions together. The first, of course, is water—or more specifically rainfall—the single most important factor in human existence. The second key idea is climate: the multi-year patterns of temperature and rainfall that define a region for its people and their livelihoods. Remember that climate is much more than weather, because it filters out the normal variations between years. The third idea is closely related—climate change. Think about it: if climate refers to many years of weather, then climate change must refer to many tens or hundreds of years.
Many people today are appropriately very concerned about one specific type of climate change: global warming. There are many models that attempt to predict the rate at which our planet is warming, and also the effects of that change in global temperature. Here we won't be focusing on global warming per se, but what you learn will leave you better informed about the discussion. In fact, I guarantee that you will know more about global warming than the vast majority of politicians who are making decisions about emissions, energy use and sea level rise. I want you to remember two things: (a) predictions of future climate need to be based on the past records, and (b) before we can assess anthropogenic factors we need to understand the natural variations. The Nile is wonderful in this regard, because we have literally thousands of years of data, both anecdotal and scientific, to show us how the climate has changed. In other words, before we can look into the crystal ball of the Kyoto Treaty, we had better know what the earth was doing prior to the start of fossil-fuel burning.
Learning Objectives
By the end of Lesson 7 you should be able to:
- Identify the major climactic characteristics of the African continent and describe how the climate has changed over time.
- Describe how and why weather patterns vary based on the distance from the equator.
- Provide examples of how the climate and climactic changes have impacted human lives and the development of civilization.
- Calculate and interpret the age of water and uncertainty for various locations in Africa.
Reading Assignment from e-Reserves
Electronic course reserves, or "e-Reserves," are articles that are available online through the University Libraries.You can access our course reserves by clicking on the Resourcestab in ANGEL and then clicking on the "Library Reserves" link within the "Penn State Library Tools" box. E-Reserves directions are also available to help you learn how to use the online system.
Deliverables
The following items are due by the end of this lesson (see the Calendar tab in ANGEL for specific due dates). Detailed information about the assignment and submission directions are included in this lesson.
- Discussion Forum: Climates of Africa, Part I
- Thought-provoking Assignment: Radiocarbon Dating and the Age of Saharan Groundwater
Questions?
If you have any questions now or at any point during this week, please feel free to post them to the Lesson 7 Discussion Forum.(That discussion forum can be accessed at any time by clicking on the Communicate tab in ANGEL and then looking in the Discussion Forums box.)
