Paper 1 Climate Change Flashcards
What is climate change?
Any significant change in the Earth’s climate over a long period
What is the most recent geological time period?
The Quaternary period
What happens during the Quaternary period?
-temperatures have shifted between cold glacial periods (100,000 years) and warmer inter-glacial periods (10,000 years)
What does global warming mean?
The term used to describe the sharp rise in global temperatures over the last century (type of climate change)
Evidence for climate change
Ice and Sediment Cores
-scientists drill into layers of ice to get long cores of ice
- a new layer is formed every year
-they analyse the gases trapped in each layer to see what the temperature was that year (can show the temperature over the last 400,000 years)
-also the remains of organisms in sediment cores found in the ocean can be analysed (can extent the temperature record back at least 5 million years)
Tree rings
-a new ring is grown each year
-they are thicker in warm, wet conditions
-scientists can take cores and count rings to see the age of the tree
-the thickness can tell them what the climate was like.
Pollen analysis
-pollen from plants is preserved in sediment
-scientists can identify the date to show what species lived at that time- due to the weather conditions
Temperature records
-since the 1850s, global temperatures have been measured accurately using thermometers- reliable short-term record
Give 3 natural causes of climate change
-orbital changes
-volcanic activity
-solar output
Explain how orbital changes cause climate change
-they affect how much solar radiation is received by the earth (more energy is more warming)
-there are variations in the way the Earth orbits:
-stretch (orbit varies from circular to elliptical)
-tilt (axis is tilted at an angle)
-wobble (axis wobbles like a spinning top)
-these may have caused the glacial and inter-glacial cycles
Explain how volcanic activity causes climate change
-big eruptions eject lots of material into the atmosphere, these can reflect the Sun’s rays back to space, so the surface cools
-activity may cause short-term changes in climate
Explain how the solar output causes climate change
-the energy output from the sun isn’t constant, it changes in short cycles
-reduced output means that the climate may be cooler in some areas
-solar output isn’t thought to have a major effect on global climate change.
Give 4 human activities that can cause climate change.
-burning fossil fuels
-farming
-cement production
-deforestation
Explain how burning fossil fuels can cause climate change
-carbon dioxide is released into the atmosphere when fossil fuels are burnt
Explain how farming can cause climate change
-farming livestock like cows produces lots of methane
-rice paddies contribute to global warming as they emit methane too
Explain how cement production can cause climate change
-cement from limestone contains carbon
-when it is produced, lots of carbon dioxide is released into the atmosphere.
Explain how deforestation can cause climate change
-plants remove carbon dioxide, so as it is burnt they stop taking it in through photosynthesis.
How does climate change affect the enviroment?
-glaciers and ice caps can melt
-sea levels rise
-floods occur more regularly
-species are declining due to warming
-precipitation patterns are changing
-distribution and quantity of some species could change and biodiversity could decrease.
How does climate change affect people?
-deaths due to heat have increased and cold have decreased
-hot and dry places are difficult to live in and inhabit
-some areas have less water availability than before
-globally, some crops have suffered from warming
-lower yields could increase malnutrition and death form starvation, especially in lower latitudes
-weather is becoming more extreme.
give 4 ways to manage climate change
-planting trees
-carbon capture
-alternative energy production
-international agreements.
what strategies aim to reduce the causes of climate change
(one word)
MITIGATION
Planting trees
this increases the amount of carbon dioxide that is absorbed from the atmosphere through photosynthesis.
Carbon capture
this is designed to reduce emissions from power stations burning fossil fuels. it involves capturing carbon dioxide and transporting it to safe places where it can be stored.
Alternative energy production
-replacing fossil fuels with nuclear or renewable sources of energy can help reduce greenhouse gas emissions.
