ATMOSPHERIC HEATING Day 1

All matter is made of atoms Matter: anything that has mass and occupies space Atom: the smallest particle of a substance that can exist by itself or be combined with other atoms to form a molecule. Molecules: groups of atoms

Temperature vs. Heat Temperature How fast atoms/molecules move. Faster movement = higher temperature Slower movement = lower temperature Heat Transfer of heat energy between substances with a different temperature. Energy ALWAYS transfers from the object with the higher temperature to the object with the lower temperature.

Situations where heat is transferred

ATMOSPHERIC HEATING Unit 5: Sixth Grade http:// /

Imagine …. You are lying in a park with your eyes closed….. You feel the warmth of the sun on your face…. What are you thinking about …. Is it the fact that it takes a little more than 8 minutes for the energy that warms your face to travel from a star that is 149,000,000 km (93 million miles) away? I thought so!

Energy in the atmosphere In the scenario, your face was warmed by energy from the sun. Earth and its atmosphere are also warmed by energy from the sun. Today we will find out what happens to solar energy as it enters the atmosphere

Radiation: Energy Transfer by Waves The Earth receives energy from the sun by radiation. Radiation is the transfer of energy as electromagnetic waves

Radiation: Energy Transfer by Waves Although the sun radiates a HUGE amount of energy, Earth receives only 2 billionths of this energy. By this small fraction is enough to drive the water cycles and weather cycles. The Earth is habitable because of the energy we receive from the sun Think of: standing in front of a fire

HEAT TRANSFER Day 2

What happens to the energy once it enters the atmosphere? Energy from the sun is absorbed by the atmosphere, land, and water is changed into thermal energy 20% is absorbed by the ozone, clouds, and atmospheric gasses 25% is scattered and reflected by clouds and air 5% is reflected by the earth’s surface 50% is absorbed by the earth’s surface.

Conduction: Energy Transfer by Contact Thermal conduction is the transfer of heat through a material. Transferred by touch. Thermal energy is always transferred from warm to cold areas. Think of: “the other side of the pillow”

Conduction: Energy Transfer by Contact When air molecules heated by the sun’s rays (radiant transfer) come into direct contact with surface of the earth, thermal energy is transferred

Convection: Energy Transfer by Circulation Convection is the transfer of thermal energy by circulation or movement of a liquid or gas Most of the energy in our atmosphere is transferred by convection. Think of: standing in front of a fan while it is blowing

Convection: Energy Transfer by Circulation As air is heated, it becomes less dense and rises. Cool air is denser, and it sinks. As the cool air sinks, it pushes the warm, less dense air up. This cycle of warm air rising and sinking causes a circular movement of air called a convection current

The Greenhouse Effect hill.com/sites/ /student_view0/brainpop_movies.htm l# hill.com/sites/ /student_view0/brainpop_movies.htm l# As you know, 70% of the radiation that enters Earth’s atmosphere is absorbed by the clouds and the earth’s surface. This energy is converted into thermal (heat) energy that warms the planet. Most of this energy will escape back into space, but our atmosphere works as a blanket that traps enough energy to make Earth livable. This process is called the Greenhouse Effect. Just like a greenhouse’s glass walls, the gases of our atmosphere allow heat in, but prevents all of the heat from escaping

The Greenhouse Effect

Radiation Balance For the earth to remain livable, the amount of energy from the sun let in by the atmosphere needs to be approximately equal to the amount that is let back out into space. This balance of incoming and outgoing is called radiation balance.

Greenhouse Gases and Global Warming Human activities such as burning fossil fuels and deforestation may be increasing the gases that trap in more thermal heat than is necessary for life to exist on Earth. Some scientists say these activities are causing average global temperatures to rise. This increase in average global temperature is called global warming. Scientists fear that this warming could affect plants and animals on Earth. This subject is highly complex and debatable!

Smoke from burning rainforests

From eye level

When the smoke clears….