Early atmosphere

Early atmosphere

Fast start

• Watch this video - see if you can work out the sentence on the next slide says

• Joseph Priestley – the discovery of gases (signed) - KS2 Science - BBC Bitesize

Fill in the Blanks

How the atmosphere of the earth has changed over billions of years

• Describe what the first atmosphere was like

• Explain how the gases in the earth's atmosphere were produced

• Suggest evidence that scientists use to support their ideas

Looking for evidence

• Scientists study similar planets to ours such as Venus and Mars to suggest how the earth's atmosphere may have changed

• Analysing layers in the earth's crust also give scientists an idea of the processes that take place.

• Watch the video - and have a go at ordering the timeline on your card sort powerpoint activity

• (25) Earth and the Early Atmosphere | Big History Project - YouTube - - https://www.youtube.com/watch?v=Gyn754vw8ZQ

Timeline sorting activity

On the powerpoint - in your groups try ordering the pictures. Move the pictures over the blue boxes and the time periods onto the grey boxes

How did you do?

• Why might the information on this timeline change?

Earth's early atmosphere

• Venus and Mars are rocky planets like earth with volcanic activity

• Scientists believe conditions on Venus and Mars are similar to the earth's early atmosphere

• These volcanoes probably formed the earth's early atmosphere, producing mainly carbon dioxide and water vapour, and some methane and nitrogen, with no oxygen

Forming the oceons

• About 4 billion years ago it is thought that cooling of the earth caused the water vapour from the volcanoes to condense and form oceans

• Water vapour levels in the atmosphere decrease

• 
  

Oxygen

• Rock layers from about 2.4 billions years suggest the beginnings of oxygen in the earth's atmosphere

• Fossilised microorganisms are believed to have produced this oxygen, as they took in carbon dioxide

Multiple Choice

What was the Earth's early atmosphere like ?

• Similar to Mars and Venus. A large amount of carbon dioxide,little or no oxygen small amounts of other gases, such as ammonia and methane

• Similar to Mercury. A large amount of oxygen, sodium and hydrogen.

• Similar to Pluto. A large amount of nitrogen.

Multiple Choice

According to scientists, both Earth and moon are...

• About 1.6 Billion Years Old

• About 4.6 Billion Years Old

• About 14 Billion Years Old

Multiple Choice

How do scientist think that early atmosphere was probably formed?

• Gases from volcanoes

• Gases released from bacteria

• They are unsure how it is formed

Multiple Choice

What was the effect of volcanoes on the Earth's early atmosphere?

• Volcanoes changed the landscape

• Volcanoes released water vapour

• Volcanoes released gases and water vapour

Multiple Choice

Volcanic "outgassings" provided sources of

• water vapor

• carbon dioxide

• nitrogen

• all of the answer choices

Multiple Choice

This gas was in high concentrations in the early atmosphere, and later condensed to form Earth's oceans.

• oxygen

• carbon dioxide

• water vapour

Multiple Choice

The early atmosphere contained a lot more water vapour than the modern atmosphere does. Where did it go?

• It condensed to form the oceans

• It escaped into space

• It was absorbed by plants

Multiple Choice

True or False: The first organisms in the ocean did not use oxygen.

• True

• False

Multiple Choice

Which gas did organisms in the sea take out of the air?

• Oxygen

• Carbon Dioxide

• Nitrogen

Multiple Choice

True or False: No animals would have been able to breathe in Earth's early atmosphere.

• True

• False

Multiple Choice

What evidence do scientists have that large quantities of oxygen entered the atmosphere?

• comets

• the rings in trees

• banded-iron formations

Multiple Choice

What produced oxygen within the early stages of our atmosphere?

• Plants

• Volcanos

• Microorganisms such as bacteria

Multiple Choice

How long ago did the Great Oxygenation Event Occur?

• 1.6 billion years ago

• 2.5 billion years ago

• 300 million years ago

Multiple Choice

What layer of the atmosphere does oxygen help make up?

• ozone

• stratosphere

Multiple Choice

Why is Earth's atmosphere important?

• It is beautiful

• It prevents pollution from happening

• Life on Earth could not exist without it