Our atmosphere What is air made out of?

The Earth's Atmosphere The atmosphere surrounds Earth and protects us by blocking out dangerous rays from the sun. It is composed of Nitrogen (78%), Oxygen (21%), and other gases (1%). It is made of atoms and molecules they have mass.

Can you feel air?

How much does air weigh?

14.14 Grams

What gasses are most important to us?

Oxygen, Nitrogen and carbon dioxide Why Are they important?

Oxygen for breathing Carbon Dioxide for plants Nitrogen to stabilize the atmosphere

Troposphere The troposphere is the lowest region of the Earth's atmosphere, where masses of air are very well mixed together and the temperature decreases with altitude. The air is heated from the ground up because the surface of the Earth absorbs energy and heats up faster than the air. The heat is mixed through the troposphere because on average the atmosphere in this layer is slightly unstable. Weather occurs in the Earth's troposphere. In fact, most clouds form in this layer.

The Earth is a closed system where materials cycle between the lithosphere (Earth), atmosphere, hydrosphere, and biosphere

What does it mean to be a “system”? What does it mean to be a “closed” system?

A “system” Definitions: “An assemblage or combination of things or parts forming a complex whole” “A coordinated complex scheme” “An assemblage of parts concerned with the same function”

The Earth as a system: the processes operating on Earth interact with one another; changes in one process, such as volcanic activity, result in changes in another, such as atmospheric composition