TOPIC 2: Weather Hazards and Climate change ☂️🌐 Flashcards
Explain how winds transfer heat from the equator to the poles. [4]
Hint: heats the Earth’s surface…, difference in temperature—> areas of high to low pressure and
1) sun heats the Earth surface unevenly and insulation is greater at equator [than poles]
2) difference in temp causes difference in air pressure
3) winds blow from areas of high pressure to area of low pressure
4) winds are apart of global atmospheric loops- loops have warm rising air (creates low pressure belt) and loops have cool falling air (creates high pressure belt).
When was the last glacial period?
15,000 years ago.
What does the term ‘climate change’ mean?
Hint: over a long period of time
- climate change, is a significant change in the Earth’s climate, over a long period of time.
How is heat transferred by ocean currents? [5]
Hint: surface current, different in water density, water freezes at the poles, creates a current, cools and sinks
- ocean currents are large scale movements of water, that transfer heat energy from water to cooler regions
- surface currents caused by winds help transfer heat away from the equator.
- there are also deep ocean currents, which are driven by difference in water density.
- water freezes at poles, meaning the surrounding water gets saltier- increasing the density.
- as it gets denser it sinks, which causes warmer water to flow in, at the surface- creates a current.
- warmer water then cools, and sinks- which contuines the cycle.
What are ocean currents?
Hint: large scale movements of water
- ocean currents are large scale movements of water, that transfer heat energy from warmer to, cooler regions. [of the globe]
How can ice cores can be used as evidence for natural climate change ?
Hint: layers of ice, drill, analysing gases trapped
- ice sheets are made up of layers of ice, and each year a new layer is formed.
- scientists drill into ice sheets to get long cores of ice.
- and by analysing gases trapped in layers of ice, they can tell what the temperature was, each year.
How can tree rings can be used as evidence for natural climate change ?
Hint: forms a tree ring, count the rings, width
- as a tree grows, it forms a new ring [called tree rings] each year- tree rings are thicker in warm and wet conditions.
- scientists take cores, and count the rings to find the age of a tree- as the thickness of each ring, shows what the climate was like.
- this is because, their width shows how warm or cold the climate was at different times.
How can pollen records can be used as evidence for natural climate change ?
Hint: preserved, identify and date, scientists now know
- pollen from plants gets preserved in sediment
- scientists can identify and date preserved pollen, to show how species were living at that time.
- Because scientists know the conditions that plants live in now, preserved pollen from similar plants, tell scientists that the climate conditions were similar.
Explain how historical sources can be used as evidence for natural climate change.
Hint: extend the record of climate change, short-term record
- historical sources can be used to extend the record of climate change, further into the past.
- this is because, using thermometers to accurately measure global temperature only gives a short-term record for temperature change.
What does the term ‘Milankovitch cycles’ mean ?
Hint: orbits the sun
- Milankovitch cycles, are variations in the way the Earth moves as it orbits the Sun
How is solar variation, a natural factor that can affect climate change ? [4]
Hint: sun’s output of energy, sunspots, solar output is reduced, earth’s climate- cooler
- solar variation- Because the sun’s output of energy isn’t constant, it changes in short cycles of about 11 years [called solar variation].
- solar variation is caused by sunspots- which are cooler areas of the sun’s surface that are visible as dark patches.
- sunspots increase the sun’s output of energy which means that when there are periods where solar output is reduced, there are very few amounts of sunspots.
- this can then cause the Earth’s climate, to be cooler in certain areas.
How is volcanic activity, a natural cause of climate change ?
Hint: eject, particles reflect the sun’s rays, short-term changes
- major volcanic eruptions, eject large quantities of material into the atmosphere
- ; as some of these particles reflect the sun’s rays back to space, this causes the Earth’s surface to cool.
- volcanic activity may then cause short-term changes in climate.
What’s one way, how industry can lead to the enhanced greenhouse effect ?
Hint: industrial processes release, energy is trapped
- Because most industries use a lot of energy, some industrial processes release greenhouse gases
- for example, cement is made from limestone but contains carbon. And when cement is produced, it releases lots of CO2 into the atmosphere.
- ; as there’s already too much greenhouse gases in the atmosphere, this means too much energy trapped- and the planet warms up.
Define the term ‘the enhanced greenhouse effect’. [2]
Hint: human activities
- the enhanced greenhouse effect is when human activities [such as industry] can cause climate change.
- this is because, it makes the greenhouse effect stronger.
Explain how transport can lead to the enhanced greenhouse effect
Hint: fossil fuels burnt, car ownership, more, warms up
- Transport can lead to the enhanced greenhouse effect because most: cars, lorries, ships and planes run on fossil fuels- this releases greenhouse gases when burnt.
- ; car ownership is rapidly increasing in some emerging countries (such as China).
- Meaning, there are more cars on the road= more greenhouse gases are released.
- But because there’s already too much greenhouse gases in the atmosphere= too much energy trapped= planet warms up.
