CT3 Flashcards
What is weather?
Weather is short-term changes to the state of the
atmosphere e.g. sunny, cloudy or rainy. It changes
daily or even hourly
What is climate?
Climate is longer term weather patterns in a place
e.g. a tropical climate. It is studied over many years
When/why has temperature increased and decreased?
- Temperature has increased when carbon-dioxide has been high. (Interglacial)
- Temperature has decreased when carbon-dioxide levels have been low. (Glacial)
Freeze-thaw weathering
When water gets into gaps in the valley side., it freezes at night and expands, breaking the rock apart.
Abrasion
Abrasion is a type of erosion. It is when scree scratches along the valley bottom, wearing it away.
Plucking
A form of erosion. It is when the glacier freezes and sticks to the valley. As it melts it plucks rock away.
What are the two types
of glaciers?
Alpine sheets and ice sheets.
When snow falls, what
does it do to the
bottom layer?
Compresses (squashes) it.
What is ice that
survives one year
called?
Firn
When layers of snow fuse
together, what is
formed?
Glacial ice
What do glaciers do to
the land as they move?
They erode the land
How many years ago
did most glaciers
retreat (disappear)?
20,000 years ago
Moraine
A mass of rocks found at the end (terminus) of a glacier.
Why are U-Shaped valleys evidence of glaciation
- A U-shaped valley is form by glacial erosion.
- As the glacier moves downhill the sediment in the sole
(bottom) of the glacier erodes the land through abrasion - Over time this creates a U-shape
- When the glacier melts, the valley is left behind as
evidence
Why are glacial striations evidence of glaciation
- Striations are formed through erosion
- As a glacier moves, the sediment in the sole (bottom) of
the glacier scrape the floor - This is abrasion
- It leaves marks on rock, providing evidence of glaciation
Why are glacial erratics evidence of glaciation
- Erratics are formed through transportation and deposition
- Glaciers transport sediment as they move downhill
- When they melt, they deposit large boulders
- This leaves large boulders in landscapes that they do not look like they belong in
What are the natural causes of climate change?
- Volcanic activity
- Changes in the earth’s orbit
- Solar variations (sunspots)
- Asteroid Collisions
How do volcanic eruptions cause climate change?
Volcanic eruptions release carbon-dioxide, warming the Earth but large eruptions of ash can also block sunlight and cool the Earth for small periods of time.
How do changes in the earths orbit cause climate change?
When it is more elliptical it is cooler as we receive less solar radiation.
When more spherical it is warmer. Right now, Earth’s orbit is becoming more elliptical.
How does solar variations cause climate change?
When solar output is lower it may cause Earth to cool down.
When there are less sun spot it is cooler and when there are more it is warmer.
How do asteroid collisions cause climate change.
Asteroid collisions throw dust clouds up, which block The Sun’s heat. This cools Earth.
What is the greenhouse effect
The process through which heat is trapped in the Earth’s atmosphere by substances known as ‘greenhouse gases.’
Why is the greenhouse effect important?
It keeps the Earth at a inhabitable temperature.
What are periods of cooling and warming known as?
A cooling period is a glacial whereas a warming period is an inter glacial.
What is the relationship between CO2 and temperature?
The more CO2 in the atmosphere the higher the temperatures are as it enhances the greenhouse effect.
Examples of greenhouse gasses
- Carbon dioxide (CO2)
- Methane (CH4)
- Nitrous oxide (N2O)
- Water vapor (H2O)
Examples of fossil fuels
- Coal
- Petrol
- Natural Gas
What human activities are increasing greenhouse gasses?
- Cows
- Deforestation
- Transportation
- Rice farming
- Energy production
- Land fill
How do cows increase greenhouse gasses?
Cows fart produce methane (CH₄) as a by-product
How does deforestation increase greenhouse gasses?
Releases CO2 AND trees
can then absorb less CO2.
How does transportation increase greenhouse gasses?
Burning petrol and diesel releases carbon-dioxide (CO2)
How does rice farming increase greenhouse gasses?
Bacteria releases methane (CH₄) when it is growing.
How does energy production increase greenhouse gasses?
Burning fossil fuels like oil/gas/coal releases CO2 and N2O
How does land fill increase greenhouse gasses?
Decaying waste releases methane (CH₄) into the atmosphere.
What is the albedo affect?
A measure of how reflective a surface is.
The ability for a surface to reflect sunlight.
e.g. sand, snow, concrete.
What countries are affected by wildfires?
Australia
Indonesia
Morocco
USA
What countries are affected by heatwaves?
USA
Spain
Japan
Pakistan
What countries are affected by flooding?
Thailand
Oman
France
India
What countries are affected by crop failure?
- Madagascar
- India
- Mexico
- Pakistan
- Western Africa
What are alpine glaciers
They form on mountainsides and move down through valleys. Sometimes they create U-shaped valleys by moving scree.
What are ice sheets
They are not limited to mountainous areas.
They form broad domes and spread out from their centers in all directions.
They cover vast areas.
How will climate change affect heatwaves?
- In the next 10 years heatwaves will become 4.1x more likely.
- Extreme heatwaves could make parts of the Middle East too hot for humans to endure.
- Globally, an extra 4.9 million people will die each year from extreme heat should the average temperature raise beyond 2C.
How will climate change affect crop failiure?
- Madagascar is the first country at risk of ‘climate change famine’ after 4 years of almost no rain.
- Extreme crop droughts (usually once a decade) will double if temperatures rise by over 2C.
- Any further and a 3rd of all the world’s food production will be at risk.
How will climate change affect wildfires?
- Virtually all of North America and Europe will be at heightened risk of wildfires at 3C of heating.
- Wildfires have large ripple effects e.g. 1 million children missing school in California.
- By the end of the century, North America will all be at risk and the continent will regularly be smothered in smoke.
How will climate change affect flooding?
- Earth’s hotter climate is causing the atmosphere to hold more water, then releasing the water in the form of extreme precipitation events.
- Unless action is taken 216 million people (mostly in developing countries) will have to leave their homes.
- In 2020, the UK had 1 month of rainfall in 48 hours.
