Climate Change Flashcards
1
Q
Evidence for climate change (quaternary)
A
- Quaternary period is 2.6 million yrs ago to today (whole of human history).
- Since the last glacial period, the climate has been warming (for 15,000 years). However, there’s been a sharp rise since 1970
2
Q
Ice and sediment cores
A
- Ice sheets are made up of layers of ice - one layer each year.
- Scientists drill into ice sheets to get long cores of ice.
- By analysing the gases, they can tell the temp every year.
- Remains of organisms found in cores from ocean sediments can be analysed. Extend record back 5 million years.
3
Q
Temp records
A
- Temp measured using thermometer since 1850.
- Historical records can go further back.
4
Q
Pollen analysis -
A
- Pollen gets preserved in sediment.
- Scientists identify and date preserved pollen to show what species were living.
- We know conditions plants live in now, so preserved pollen can show that climate conditions were similar.
5
Q
Tree rings
A
- Every year, a tree grows a new ring - and thicker in warm, wet conditions.
- Take cores and count rings to find age.
- Reliable source for 10,000 years.
6
Q
Orbital Changes
A
- Affect how much solar radiation the Earth receives - more energy = more warming.
- The earth can stretch - earth’s orbit varies from solar to elliptical.
- Can tilt - axis is tilted at an angle.
- Wobble - axis wobbles like a spinning top.
- The changes may have caused the glacial and interglacial changes of the Quaternary period.
7
Q
Volcanic Activity
A
- volcanos eject lots of material into the atmosphere.
- Some of these particles reflect the sun’s rays back out to space, so the Earth’s surface cools.
- Can cause short-term changes
8
Q
Solar Output
A
- Sun’s energy output changes every 11 years.
- Reduced solar output > Earth’s climate can become cooler.
- Not a major impact
9
Q
Burning fossil fuels
A
Co2 released when fossil fuels like coal, oil and gas are burnt.
10
Q
Farming
A
- Farming livestock produces methane.
- Rice paddies contribute to global warming.
11
Q
Cement production
A
Cement made from limestone, which contains carbon. So lots of co2 released when cement is made.
12
Q
Deforestation
A
- Plants remove co2 from the atmosphere and convert into organic matter through photosynthesis.
- When trees are cut down, co2 isn’t absorbed.
- Co2 released when trees are burnt as fuel/to make way for agriculture.
13
Q
How does climate change affect the environment?
A
- Warm temps cause glaciers to shrink, ice sheets melt.
- Sea ice shrinking, leading to loss of polar habitats.
- Rising sea levels. Floods more regular. Coastal Erosion increases.
- Species lost e.g coral reefs. As they are suffering from bleaching.
- Precipitation patterns are changing.
- Species now live at higher latitudes and some a habitats are being damaged or destroyed because of climate change > species adapted could go extinct e.g limits bamboo growth > red pandas go extinct.
14
Q
How does climate change affect people?
A
- Deaths due to heat increase and due to cold.
- Areas could become so hot and dry they’re difficult to inhabit. Areas could be lost to flooding.
- Water availability decreases.
- Crops have suffered from climate change in countries such as Argentina (low latitude) but in high-latitude countries the crops can benefit from warmer conditions.
- Lower crop yields can result in malnutrition, ill health and death from starvation.
- Extreme weather > more money spent predicting weather events, reducing their impacts and rebuilding.
15
Q
Carbon Capture
A
- Designed to reduce emissions from power stations burning fossil fuels.
- Involves capturing co2 and transporting it to safe places where it can be stored e.g underground.
