Les 2 - Klimaatverandering

• Aardrijkskunde
• Middelbare school
• havo
• Leerjaar 3

Planning

• How does climate work in a natural setting (10 mins)
• What is the influence of humanity? (10 mins)
• Feedback loops (5 mins)
• Homework (15 mins)

The natural situation

• Atmosphere
• The greenhouse effect

• Natural climate change

What is the atmosphere made of?

A blanket of gasses around the earth

• 78% Nitrogen (N2)
• 21% Oxygen (O2)
• 0,9% Argon (Ar)
• 0,03% Carbondioxide (CO2)

Some more random stuff

The (natural) greenhouse effect

• The atmosphere works just like the glas of a greenhouse. Sun can get in, but some gets trapped inside.
• Carbondioxide (CO2) is one of the gasses that traps heat in the atmosphere. 
• The trapping of this warmth is the greenhouse effect

Natural climate change

• Climate of way back
• Glacials and interglacials

Natural climate change

• During the Cretaceous
• 70 million years ago
• The Netherlands were tropical
• Average temperature on earth was way higher than right now

What is the influence of humans?

• The enhanced greenhouse effect
• Feedback loops

What is the influence of humans?

The enhanced greenhouse effect

Because of the sharp increase of CO2 and other greenhouse gasses in the atmophere the natural greenhouse effect gets enhanced. Thats what we call the enhanced greenhouse effect

Feedback loops

• Negative -> Slows itself down
• Positive -> Makes itself go faster

Positive feedback loops

• Area's with a lot of permafrost have a lot of methane stored underground
• If that melts this methane gets in the air
• Methane is 80 - 100 times stronger as a greenhouse gas than CO2

Permafrost melts

Methane gets in the air

Earth warms further

The greenhouse effect gets enhanced

Homework

Assignment 4, 5, 6 of §6.2