For the InstructorThese student materials complement the Humans' Dependence on Earth's Mineral Resources Instructor Materials. If you would like your students to have access to the student materials, we suggest you either point them at the Student Version which omits the framing pages with information designed for faculty (and this box). Or you can download these pages in several formats that you can include in your course website or local Learning Managment System. Learn more about using, modifying, and sharing InTeGrate teaching materials.
A General Model of Earth's Climate
Because climate is intricately linked to chemical weathering, let us take a quick look at Earth's climate system.
Temperatures are hottest in the tropics, the zone between 0° and 25° degrees N and S latitude. This is because the sun angle (the angle between incoming sun rays and Earth's surface) at these latitudes is the highest, so solar radiation is more concentrated. Temperatures are lowest at the poles, but are also low at high elevations.
Air Pressure and Precipitation:
The globe shows how surface air pressure (also called atmospheric or barometric pressure) forms distinct zones that align with latitude.
Low pressure zones mark where air rises and precipitation occurs. For example, due to low pressure, rain forests are found along the equator. (The high temperature also helps, because with high temperatures comes a lot of evaporation, which provides a lot of water vapor to condense to form rain.) In zones of high pressure, air sinks, which prevents condensation. High-pressure zones tend to have low amounts of precipitation; several deserts are located along 30° N and S; the poles also have high pressure and so are also deserts.