1. Chapters
3 & 15
Earth’s Environmental Systems:
Geosphere & Atmosphere

2. Lesson 3.2 Systems in Environmental Science
Dust storm, Stratford Texas, 1930s
Positive feedback loops can help erosion turn a fertile field to desert in just a few years.

3. Negative feedback loop
Lesson 3.2 Systems in Environmental Science
A. Interacting Systems
Inputs into Earth’s interconnected systems include energy, information, and matter.
Feedback loops regulate systems.
Negative feedback loops: Result in stabilization of a system
Positive feedback loops: Result in a system moving to an extreme
Negative feedback loop
Did You Know? Predator-prey cycles are negative feedback loops. If prey populations rise, predator populations can rise in response, causing prey populations to fall. Then predator populations may decline, allowing prey populations to rise again, and so on.

4. Lesson 3.2 Systems in Environmental Science
Spheres of Function
Earth can be divided into spheres that are defined according to their location and function.

5. Lesson 3.3 Earth’s Spheres
The movement of Earth’s plates has formed the deepest ocean trenches and the highest mountains.

6. B. The Geosphere Crust: Thin, cool, rocky outer “skin”
Lesson 3.3 Earth’s Spheres
B. The Geosphere
Rocks and minerals on and below Earth’s surface:
Crust: Thin, cool, rocky outer “skin”
Mantle: Very hot and mostly solid
Core: Outer core is molten metal, inner core is solid metal
Rock formation, Ouray National Wildlife Refuge, Utah

7. 2. Crust and mantle are divided into:
Lesson 3.3 Earth’s Spheres
2. Crust and mantle are divided into:
Lithosphere: Crust and uppermost mantle; divided into tectonic plates
Asthenosphere: Soft middle mantle; heated by outer core
Lower mantle: Solid rock
Convection currents in the asthenosphere move tectonic plates.
Collisions and separations of the plates result in landforms.
Volcano lava

8. Divergent Transform Convergent
Lesson 3.3 Earth’s Spheres
3. Tectonic Plates – large pieces of the lithosphere that are moving; the Earth has 15 major plates.
There are three major types of plate boundary:
Divergent
Transform
Convergent

9. C. The Biosphere and Atmosphere
Biosphere: The part of Earth in which living and nonliving things interact
Atmosphere: Contains the gases that organisms need, such as oxygen; keeps Earth warm enough to support life
Earth’s atmosphere, seen from space

10. 3. Properties of the Atmosphere
(Lesson 15.1 Earth’s Atmosphere)
3. Properties of the Atmosphere
Composition: 78% nitrogen, 21% oxygen, and 1% other gases
Temperature: Varies upon location
Pressure: In general, air pressure decreases with altitude; can be measured using a barometer.

11. 4. Layers of Atmosphere Troposphere: 0–11 km; movement of air, weather
Did You Know? The stratosphere and mesosphere are cold, but the upper thermosphere can be hotter than 1500°C.
Troposphere: 0–11 km; movement of air, weather
Stratosphere: 11–50 km; ozone layer, absorbs and scatters UV rays
Mesosphere: 50–80 km; meteoroids burn up
Thermosphere: 80+ km; disturbances produce aurora borealis

12. Troposphere
(a) location surface of the earth to 10km
(b) This layer contains most of our water vapor (clouds and rain) and wind.
(c) Weather occurs here.
(d) This layer traps the sun’s heat which is called: The Greenhouse Effect

13. (a) Contains our ozone layer which has the chemical symbol O3.
Stratosphere
(a) Contains our ozone layer which has the chemical symbol O3.
- It’s function is to: block harmful ultraviolet (UV) radiation.

15. D. The Hydrosphere Consists of Earth’s water
Lesson 3.3 Earth’s Spheres
D. The Hydrosphere
Consists of Earth’s water
Most of Earth’s water (97.5%) is salt water.
Only 0.5% of Earth’s water is unfrozen fresh water usable for drinking or irrigation.
Earth’s available fresh water includes surface water and ground water.
Greenlaw Brook, Limestone, Maine
Did You Know? If it is depleted, groundwater can take hundreds or even thousands of years to recharge completely.