Introduction to Climate Change Flashcards
Weather
Short term day to day changes in the atmosphere.
Climate
The average weather conditions over a long period- at least 30 years.
Ice Core- How does it work?
Frozen record of past climates, like a time capsule.
Within these layers the ice contains air bubbles which contain carbon dioxide and oxygen isotopes.
Are ice cores accurate and reliable?
The sequences of sea level change links very closely with oxygen and CO2 isotope levels suggesting that this is a very reliable source. However, some people question the causal link.
Pollen Analysis- How does it work?
Pollen is produced by all plants and can be extracted from sediment cores in peat bogs and lake beds.
Pollen grains are preserved in waterlogged sediments.
By analysing pollen we can seen how ecosystems have changed in response to climate change.
Is pollen analysis accurate and reliable?
Not as reliable- as accurate pollen reconstructions rely on good preservation of pollen. Long pollen sequences are rare, and vegetation change may lag behind “climate change”.
Tree Ring Data- How does it work?
Many trees are sensitive to changes in temperature, sunlight and precipitation.
In warm years, trees have wide rings and vice versa.
Record can go back 10 000 years.
Is Tree Ring Data reliable?
Good reliability- however, tree records only give localised records.
Paintings and Written Accounts- How does it work?
Actual visuals and descriptions of what the landscape was like.
Are paintings and written accounts reliable?
Unreliable- these sources did not set out to record climate, and must be used with care. They are usually local, and difficult to generalise.
Glacial Retreats- How does it work?
A condition occurring when backward melting at the front of a glacier takes place.
Glaciers change in response to climate change. We can look at old photos/maps/paintings to measure direct differences in glacial positions.
What is the tipping point?
A tipping point is when we’ve reached a point where changes are irreversible. It’s a phrase that can be applied to Global climate change or to individual feedbacks (which themselves could lead to a tipping point).
E.g if enough Arctic Sea is lost then the albedo effect will be reduced so much that the temperature of the region will rise significantly and the remaining ice will melt.
