Topic 1 - Hazardous Earth Flashcards
Explain why low latitude locations receive more heat than places close to the poles?
The sun’s rays have to heat up a smaller surface area and travel through less atomosphere at the equator compared to the poles making the equator warmer than the poles.
What is high pressure?
As air cools it becomes more dense and it falls. This transfers heat to the ground. This leaves clear skies and little/no rainfall.
What is low pressure?
As air is heated by the ground it becomes less dense causing it to rise. It transfers heat to the atmosphere, cools and then condenses. This creates clouds and rain.
What are the atmospheric circulation cells called?
Polar Cell
Ferrel Cell
Hadley Cell
Where is heat moved from and to?
- The sun warms the earth at the equator creating a low pressure belt.
- The cool air moves out to 30° North and South to create a high pressure belt.
- The cool air reaches the ground surface and moves as surface winds either back to the equator or towards the poles.
- At 60° the warmer air meets the colder sir from the poles. The warmer air is less dense than the cold air so it rises creating low pressure.
- Some of the air moves back towards the equator and the rest moves back to the poles.
- At the poles the cool air sinks creating high pressure. The high pressure air is drawn back towards the equator as surface winds.
How do ocean currents move heat from the equator to the poles?
Surface currents are caused by winds and help transfer heat away from the Equator (e.g the Gulf Stream brings warm water from the Caribbean to Western Europe).
Deep Ocean Currents:
When water freezes at the poles the surrounding water gets saltier increasing in density. It therefore sinks causing warmer water to flow in at the surface - creating a current. This warmer water is cooled and sinks continuing the cycle. This cycle moves water in a big loop round the world (this is known as the thermohaline circulation).
Explain how atmospheric circulation causes high pressure areas places like Tindouf?
Sinking air from the Ferrel and Hadley Cells create high pressure meaning it is very arid and has a high level of solar radiation.
Explain how atmospheric circulation causes low pressures areas places like Singapore?
Rising air from the Hadley Cells meeting causes a low pressure zone meaning it has lots of rainfall but has a high level of solar radiation leaving it very humid.
What are the four different natural factors that have caused world climates to change over the last 400,000 years?
Asteroid Collisions: Asteroids hitting the Earth’s surface throw up a huge amount of dust into the atmosphere which prevent the Sun’s particles from reaching the Earth’s surface.
Solar Output Variation: The sun’s output of energy isn’t constant. Periods when solar output is reduced may cause the Earth’s climate to become cooler.
Volcanic Activity: Major volcanic eruptions eject large quantities of material into the atmosphere. These block the sun’s rays from reaching the earth’s surface so it cools.
Orbital Change.
Orbit, Tilt and Wobble – what are these and why do they cause variations?
Strech (eccentricity): the path of the Earth’s orbit around the sun changes from an almost perfect circle to an ellipse.
Tilt: the Earth’s axis is tilted at an angle as it orbits the sun.
Wobble (procession): the axis of the Earth wobbles like a spinning top.
These cycles affect the amount of solar radiation the Earth recieves.
What evidence do we have that tells us about previous temperatures?
Trees Rings: the thickness of each ring depends on the climate when the ring was formed - when its warmer the rings are thicker.
Ice Cores: Scientists drill into ice sheets to get long ice cores of ice. By analysing the gases trapped in the layers of ice they can tell what the temperature was each year.
Historical Records: Diaries and paintings, etc, can show what the climate was like in the past.
Give two pieces of evidence which show the earth’s climate was:
a. Warmer
Harvest records show that England was warm enough to grow large amounts of grapes during the Medieval Warm Period (900-1300).
Tree ring data suggests this was also the cause during Roman times when temperatures were almost 1°C warmer than today.
Give three pieces of evidence which show the earth’s climate was:
b. Colder
Paintings from the 17th Century show the London Frost Fairs which took place on a frozen River Thames during the Little Ice Age.
Historical Records talk about Arctic ice reaching as far south as Scotland.
How have humans enhanced the greenhouse effect (concentration of gasses)?
Humans are adding too many greenhouse gases into the atmosphere which means more heat is being trapped and the planet is being warmed up.
Give reasons how the following have caused enhanced greenhouse effect and climate change:
a. Industry
- Most industry uses a lot of energy
- Some industrial processes also release greenhouse gases
- Industrial waste may end up in landfill sites where it decays releasing methane
Give two reasons how the following have caused enhanced greenhouse effect and climate change:
b. Energy Production
CO2 is released into the atmosphere when fossil fuels are burnt
Give two reasons how the following have caused enhanced greenhouse effect and climate change:
c. Transport
Most transport runs on fossil fuels which release greenhouse gases when burnt
Car ownership is rapidly increasing in countries which are developing, this means there are more cars on the road which increases congestion. As a result car engines are running for longer, so the amount of greenhouse gases released increases.
Give two reasons how the following have caused enhanced greenhouse effect and climate change:
d. Farming
Farming of livestock produces a lot of methane
Rice paddies have to flood fields which emits methane
Trees absorb and store CO2. When they are cleared for agriculture it stops the absorbtion of CO2 which leaves more CO2 in the atmosphere
Give evidence to explain how each of the factors below show that climate change is happening:
a. Sea levels
Glaciers are shrinking and ice sheets are melting which is adding to the sea making the sea levels rise.
Water in the oceans expands as it gets warmer. This is called thermal expansion.
Since 1901, sea levels have risen by almost 0.2m.
Give evidence to explain how each of the factors below show that climate change is happening:
b. Global temperatures
Temperstures have increased by newely 1°C since 1880
The top ten warmest years since records began have all been since the year 2000
Give evidence to explain how each of the factors below show that climate change is happening:
c. Arctic ice
The extent of arctic sea ice in winter has decreased by more than 3% each decade over the past 35 years.
Give evidence to explain how each of the factors below show that climate change is happening:
d. Extreme weather
Since 1950 that has been a higher frequency of heat waves and many areas and fewer cold weather extremes.
In the UK more rainfall records are broken in 2010 to 2020 then in any other decade on record.
What are emission projections? Why do we need them? What human and physical reasons affect them? Why can’t we be more certain about the future climate temperature?
How the climate might change and the consequences of any changes.
Physical Porcesses: e.g. the effect of volcanic eruptions on the climate
Human: e.g. the growth of industry or the development of clean energy
Predictions have to take into account population increase and economic development.
We don’t know how the natural factors will have an impact on climate change.
We don’t know what attempts there will be to manage the amount of greenhouse gases or how successful they’ll be.
Explain a consequence of climate change that will:
a. Make people poorer
b. Affect human health
c. Lead to overcrowding in some areas
d. Reduce food growth
e. Cause damage to houses/lost business
Deaths due to heat
To hot or dry to inhabit
Low-lying coastal areas lost to the sea
Migration and overcrowding
Some crops have suffered from climate change
Some farmers in higher latitudes are benefiting from the warmer conditions
Malnutrition, ill health, death from starvation
More money spent on prediction, reducing impacts and rebuilding
