M2L3 - Climate Cont. Flashcards
1
Q
Written or Oral histories
A
- Either direct or indirect
- Nautical journals recording weather conditions
- Timing of harvest dates
- Oral history of lived experiences
2
Q
Corals
A
- Use calcium carbonate to build their skeletons
- Complex relationship between temp, light, nutrients
- Growth impacted by pH, salinity
- Also trap oxygen and other elements (can tell us about past environment)
3
Q
Pollen
A
- Often deposited in sediment records
- Unique shapes to different species of plants
- Can inform what was growing at a certain location
- Used in conjunction with sediment dating
4
Q
Ice cores
A
- Have snow and ice accumulated across millennia
- Contain dust, air bubbles, isotope signature
- Capture a signal at time of deposition
- Can provide information on many climate variables and volcanic activity
5
Q
Tree ring analysis
A
- Dendrochronology
- Can provide climate and environmental parameters
- Width of ring represents growth
6
Q
Lake and ocean sediments
A
- Deposited at different rates, depending on the environment
- Can include pollen, diatoms, other biological records
- Thickness of layers can give info on hydrology and land use
7
Q
Earth’s eccentricity
A
- Orbit isn’t perfectly circular
- Eccentricity is a measure of the departure from a perfect circle
- Cycle occurs over ~100k years
- Currently at most circular
8
Q
Obliquity
A
- Measure of change in axis of rotation
- Larger the tilt, the more extreme the seasons are
- 41k year cycle
9
Q
Axial precession
A
- How close we are to the sun in summer
- 23k year cycle
10
Q
Earth’s climate record
A
- Lack of data from before 500 million years ago
- Temporal resolution of data gets worse as you go back in time
11
Q
Pleistocene climate
A
Rhythmic patterns
12
Q
Holocene climate
A
Stability
13
Q
Milankovitch cycles
A
- Series of variations in the Earth’s orbit around the sun that cause climate change
- Still ongoing, may explain small amounts of change
- Can’t explain the rapid rate of change seen since industrialisation
- Currently in interglacial period, should be cooling not warming
14
Q
Cretaceous alberta
A
- 144 to 66 million years ago
- Death and decomposition of plant and marine life
- Bacteria broke down light oil resulting in Bitumen
15
Q
Where did meteor that killed dinosaurs land
A
Chicxulub crater, mexico
