1. Chapter 1.1 Earth as a System

2. Branches of Science Earth Science –The study of the Earth, its atmosphere, and the universe surrounding it. Biology –Also referred to as Life Science. –The study of living things. Chemistry –The study of the interaction of matter. Physics –The study of motion.

3. Past View…Branches of Earth Science In the past, Earth Science was viewed as having 4 distinct and separate branches. Geology –The study of the solid Earth as well as the processes that change and shape it. Examples) rocks, volcanoes, rivers, glaciers Astronomy –The study of the universe beyond Earth Examples) stars, the Sun, the Moon, planets Oceanography –The study of the Earth's oceans Examples) ocean temperatures, saline (salt) levels Meteorology –The study of the Earth’s atmosphere Examples) weather patterns, tropical storms

4. Today's view…Earth System Science Earth is more than a collection of parts Each branch of Earth Science is connected to one another

5. What is a System? A system is a kind of model; a part of the universe that can be studied separately –A model is a representation of an object, a process or a phenomenon. Scientists often describe the natural world by using models such as open and closed systems

6. Closed System Energy, such as sunlight, may enter, but matter doesn’t enter or leave Example) Sun Tea –Sunlight can enter –Heat can leave –If jar is tipped, tea stays in The jar of tea does not share matter with its surroundings, only energy

7. Another Example Deep-Sea Submersible –Minimal loss of energy to surrounding ocean –Keeps water out protecting researchers –Keeps air in so researchers can breathe

8. Open System The system and its surroundings freely exchange both energy and matter Example) glass of iced tea –Tea can evaporate –A bug can fly in (ew!) –A lemon slice and a straw are added

9. Another Example An island –Sunlight strikes the surface warming it –Rain falls onto the island –Sediment runs off into the ocean

10. Is Earth Open or Closed? Scientists consider Earth to be essentially closed –Energy is received from the sun and most is reflected back –Overall Earth’s mass remains relatively constant System is not entirely closed –Atmosphere loses hydrogen atoms to space –Meteorites enter the atmosphere