Chapter 1 The Nature of Science Section 1.1 – Earth Science

What is Astronomy? Study of objects beyond Earth’s atmosphere.

Astronomy In the past many astronomers merely described the location of objects in space in relation to one another. Today, these Earth scientist study the universe and everything in it, including Earth, its neighbors, and other bodies in the universe.

What is Meteorology? Branch of Earth science that studies the air that surrounds our planet.

Meteorology Meteorologists study the forces and processes that cause the atmosphere to change to produce weather. These Earth scientists also try to predict the weather and how changes in weather might affect Earth’s climate.

What is Geology? Study of materials that make up Earth and the processes that form and change these materials.

Geology Geologist identify rocks, study glacial movements, interpret clues to Earth’s 4.6 billions years history, and determine how forces change our planet, among many other things.

What is Oceanography? Study of Earth’s oceans including the creatures that inhabit its water, its physical and chemical properties, and the effects of human activities.

Oceanography Oceanographers study the creatures that inhabit salty water, measure different physical and chemical properties of the oceans, and observe various processes in these bodies of water. Some oceanographers study the effect of human activities on Earth’s saltwater bodies.

What is Lithosphere? Earth’s rigid outer shell, including the crust and the solid, uppermost part of the mantle.

The Lithosphere There two kinds of crust: Continental Crust - Is made mostly of a rock called granite. Oceanic Crust - Is mainly basalt, a rock that is denser than granite. Earth’s mantle: Is mainly composed of a rock called peridotite.

The Lithosphere Earth’s upper mantle behaves like: A rigid solid, while other parts are partially molten and flow like a soft plastic; this part is the asthenosphere. Core – made of iron and nickel. It is beneath Earth’s mantle The core is divided in two parts: Outer – which is the liquid part. Inner - which is the solid part. (The core and the asthenosphere are NOT parts of the Lithosphere, but they do interact with this system to produce many of features at the planet’s surface.) Lithosphere and asthenosphere interact to produce volcanoes, mountains and earthquakes.

What is hydrosphere? All the water in Earth’s oceans, lakes, seas, rivers, and glaciers plus all the water in the atmosphere.

The Hydrosphere About 97% of Earth’s water exists as salt water. The remaining 3% is fresh water contained in: Glaciers Lakes Rivers Groundwater

What is Atmosphere? Blanket of gases surrounding Earth that contains about: 78% nitrogen, 21% oxygen, and 1% other gases such as argon, carbon dioxide, and water vapor.

The Atmosphere Necessary for respiration by most living things, Protects Earth’s inhabitants from harmful radiation from the Sun, Helps to keep the planet at a temperature suitable for life.

What is Biosphere? All of Earth’s organisms and the environment in which they live.

The Biosphere Earth’s biosphere appears to be unique in that scientist have not yet found any confirmed evidence of life on other planets in our solar system or elsewhere in the galaxy.

Interdependent Systems Earth’s biosphere, lithosphere, hydrosphere, and atmosphere are interdependent systems. For example - today’s organisms, including humans, continue to change the atmosphere through their life processes and activities. (Earth’s present atmosphere formed millions of years ago as a result of volcanic activity, respiration and transpirations by ancient organisms, and photosynthesis.)

Earth Science in Your Everyday Life We are all part of the biosphere. We live on Earth’s crust, which is part of the lithosphere We breathe the gases in the atmosphere. We also depend on water, which makes up the hydrosphere.