Period 1

Chapter 2 section 2 Earth as a system

Objectives of most List an spheres Earth the with Compare Open system characteristics Earth Closed system important the with

Objectives Compare an open system with a closed system. List the characteristics of Earth’s four major spheres.

Discussion How are energy and matter added to and removed from the Earth system?

Discussion Energy is added by sunlight and from Earth’s interior, and is removed by radiation into space. Matter is added when meteorites collide with Earth and is removed when spacecraft are launched. Matter is also removed by the steady loss of gases into space

Earth-System Science An organized group of related objects or components that interact to create a whole is a system. Have boundaries Vary in size Have matter and energy that flow through them Linked together

Earth-System Science The operation of the Earth system is a result of interaction between the two most basic components of the universe: matter and energy. Matter is anything that has mass and takes up space. Matter can be atoms or molecules, such as oxygen atoms or water molecules, and matter can be larger objects, such as rocks, living organisms, or planets. Energy is defined as the ability to do work. Energy can be transferred in a variety of forms, including heat, light, vibrations, or electromagnetic waves.

Critical Thinking Use the picture in the next slide to Compare How is a closed system different from an open system?

Open system VS. Closed system

Open system VS. Closed system 1. In a closed system, what is exchanged with the environment? 2. How does an open system differ from a closed system? 3. From where do both systems get energy? 4. Aquariums function as what type of system? Explain your answer. 5. Is Earth as a planet an open or closed system? Are the systems functioning on Earth, such as the rock cycle or water cycle, open or closed systems? Explain your answer.

Open system An open system is a system in which both energy and matter are exchanged with the surroundings. The open jar in Figure 2 is an open system. A lake is also an open system. Water molecules enter a lake through rainfall and streams. Water exits a lake through streams, evaporation, and absorption by the ground. Sunlight and air exchange heat with the lake. Wind’s energy is transferred to the lake as waves.

Closed system A closed system is a system in which energy, but not matter, is exchanged with the surroundings. The sealed jar in Figure 2 is a closed system. Most aquariums are open systems because oxygen and food must be added to them, but some are closed systems. Closed-system aquariums contain a variety of organisms: plants, which produce oxygen, and aquatic animals, some of which are food for others. Some of the animals feed on the plants. Animal wastes and organic matter nourish the plants. Only sunlight enters from the surroundings.

The Earth System Technically, all systems that make up the Earth system are open. But the Earth system is almost a closed system because matter exchange is limited. Energy enters the system in the form of sunlight and is released into space as heat. Only a small amount of dust and rock from space enters the system, and only a fraction of the hydrogen atoms in the atmosphere escape into space.

Earth's Four Spheres Video paywall_the-four-spheres-of-the-earth

Earth's Four Spheres The blanket of gases that surrounds Earth's surface is called the atmosphere.  All of Earth's water makes up the hydrosphere. The mostly solid part of Earth is known as the geosphere. The biosphere is composed of all living things in the geosphere, in the hydrosphere, and in the atmosphere.

Critical Thinking Describe ways that you interact with each of Earth’s four spheres every day. Give one example for each sphere.

Critical Thinking Apply Concepts Is the human body a closed system or an open system? Use examples to support your answer

Activity

Wrap Up Exit cards

Period 2 Informational Text Strategies

Objectives Analyze Earth science informational text using a systems thinking approach.

Earth’s Energy Budget What is Earth’s main source of energy? What percentage of Earth’s energy comes from this source? More than half of the sun’s energy is absorbed by what? How does this absorption rate compare with the amount of energy absorbed by the atmosphere? What is the net effect of clouds on absorption of solar energy? If a glacier were part of the picture, what effect would that have on the net absorption or reflection of solar energy? Explain your answer. The transfers of energy between Earth’s spheres can be thought of as parts of what?

Groups Presentations