Climate change Flashcards
Give 3 pieces of short term evidence of climate change.
(how we would measure the change in climate)
- Recording of Global temperatures by Met Office using weather stations, satellites, etc. Temps have increased by 1 degree in the last 100 years. We have only had this data since 1860.
- Photographs and recordings of shrinking glaciers.
- Recordings of sea levels, they are rising by 1cm per decade.
Give 4 pieces of long term evidence of climate change.
- Ice cores
- Sediment cores
- Tree rings
- Pollen samples
How far back can ice cores go?
around 400,000 years
How far back can tree rings go?
around 1,000 years
Describe an ice core.
A sample of ice, taken by drilling through a glacier or ice sheet. to detect changes in temperatures.
Ice cores contain small bubbles of gas which preserve actual samples of the Earth’s ancient atmosphere.
By looking at the amount of carbon dioxide (CO2) in different layers of the ice, scientists can tell whether the climate was warm or cold.
Describe a tree ring.
These rings can tell us how old the tree is, and what the weather was like during each year of the tree’s life. The light-coloured rings represent wood that grew in the spring and early summer, while the dark rings represent wood that grew in the late summer and autumn.
Describe a sediment core.
Sediment falls to the bottom of the sea. This involves things like dead fish and seaweed.
Overtime the ocean has been colder and warmer and different animals and plants lived in these different times.
Scientists can analyse each layer to see the types of sea life and then work out if the sea was warm or cold.
What is an interglacial?
Where not much of the earth is covered in ice.
What is a glacial?
When very much earth is covered in ice
(aka ice age)
List 3 natural causes for climate change.
- Orbit changes
- Solar output
- Volcanic activity
Describe orbit changes as a natural cause for climate change.
Every 100,000 years the earth changes from an elliptical orbit (oval) to a circular orbit.
When it is warmer we get an elliptical orbit causing an interglacial. When it is cold there is a circular orbit causing a glacial.
Circular= Cold
Describe solar output as a natural cause for climate change.
Sun spots on the suns surface that radiate out more energy making the earth warmer. They follow an irregular cycle that lasts about 11 years.
However this hasn’t happened in about 50 years.
Describe volcanic activity as a natural cause for climate change.
Major volcanic eruptions lead to a brief period of global cooling.
Eruption of ash and SO2 (sulphur dioxide). This blocks the sun from getting into the earth making it cooler.
E.g. Pinatubo in 1991. Sunlight reaching the earth was reduced by 10%.
Explain the human cause for climate change.
Since the industrial revolution- but only getting very bad in the 60’s- as more of the world is industrialised, more cars more planes, we eat more cows and cut down more trees.
The greenhouse gas layer has gotten thicker, so it traps more heat, so the temperature of the earth is increasing.
GHG= CO2 and methane.
–> burning coal, oil and gas.
What is mitigation?
Mitigation aims to reduce the cause of the problem by limiting or preventing GHG’s and protecting carbon sink.
