Chapter 9 - Lithosphere

Question 1

What is permafrost? /5

Answer 1

Soil that has been frozen (has a temperature of 0C or below) for at least two years

50% of Canada’s soil is permafrost

Makes agriculture impossible

Can go as deep as 500m

Is sensitive to external influences

Question 2

What is the Active Layer? /5

Answer 2

Upper layer of permafrost

That’s during the warmer seasons

When thawing, allows brief growing season

Freezes once winter comes around again

Buildings built on the layer can collapse due to the active layer so longer being solid

Question 3

What is a solution to prevent buildings from collapsing when the active layer thaws? /2

Answer 3

Steel rods/poles are built under the building/infrastructure to prevent sinkage and/or collapse.

The rods must me long enough to reach all the way to the permafrost layer (lies underneath the active layer).

Question 4

What is the permafrost thawing cycle? /4

Answer 4

Temperature rises
⬇️
Permafrost bogs (wet sides of land) thaw
⬇️
Bogs release methane (pockets are found in the active layer and the permafrost)
⬇️
More heat is absorbed by the atmosphere (due to the increase of greenhouse gases (CH4) in the air).

REPEAT

Question 5

What are renewable resources? /2

Answer 5

A natural resource that is replaced NATURALLY at a rate faster than the rate of consumption of humans

Ex. Wind
Solar
Hydroelectric
Geothermal

Question 6

What are non-renewable energy resources? /2

Answer 6

A natural resource that cannot be regenerated on a scale which can sustain its consumption by humans (cannot be equivalent to the amount consumed)

Ex. Wood
Coal
Oil
Gas

Question 7

What are fossil fuels? /3

Answer 7

Result from the transformation of organic residue

Consists of:
Oil
Coal
Natural gas

2/3 of the world’s electricity is produced from fossil fuels

Come from:
Marine animals/algae
Terrestrial animals

Emit thermal energy which is then converted into mechanical energy

Question 8

What are the disadvantages of fossil fuels? /5

Answer 8

Release a large amount of Carbon Dioxide (CO2)

Resulted in an increase in climate change

Countries depending on this source of energy are found in a polluted and unhealthy state

Can have a big affect on the population, agriculture, animal life

Releases other pollutants:
Sulphur oxide (SO2)
Nitrogen oxides (NOx)
Methane (CH4)

Question 9

How is fossil fuels a source of energy? /2

Answer 9

When burned they emit THERMAL ENERGY

Thermal energy can then by converted into mechanical energy or electrical energy

Question 10

What is thermal energy?

Answer 10

Energy produced by burning fossil fuels

Question 11

What is combustion?

Answer 11

Burning of carbon compounds in the presence of oxygen

Question 12

What is nuclear energy? /5

Answer 12

Energy stored in the bonds between particles in the nucleus of an atom

Can be converted into electrical energy

Releases no greenhouse gases

Often uses Uranium to make nuclear energy

NON-RENEWABLE ENERGY SOURCE

Question 13

What are the disadvantages of nuclear energy? /2

Answer 13

Emits:
Radioactivity
Radioactive waste

Both of those by-products can last up to 100 years

Question 14

What is fission? /2

Answer 14

The splitting of atoms that creates nuclear energy

Caused when an neutron hits a uranium atom

Question 15

What is Geothermal energy? /2

Answer 15

Energy that comes from the internal heat of the Earth

A renewable resource

Question 16

How does geothermal energy work? /4

Answer 16

1. Fluid circulated deep underground
2. The fluid is then heated by the molten rock of the lithosphere
3. The fluid is evaporated which then turns the turbine of a electrical generator
4. It is then converted into electricity or used directly to heat buildings

Question 17

What are the pros and cons of geothermal energy? /2(4)

Answer 17

Pros:
Reduces conventional heating costs
Reduces CO2 emissions
Uses a renewable energy source

Cons:
System installation is much more expensive that conventional heating