Greenhouse affect
the process through which heat is trapped near Earth’s surface by substances known as ‘greenhouse gases.
Plate tectonic super cycle
- Super continent and ocean
- extension and sagging
3.rifting and break up - Disperse and subduction
- Slow subduction and rifting
Deccan and Siberian traps
Massive Mafic eruptions that can last for entries, releasing huge amounts of lava and vast amounts of sulfur dioxide and carbon dioxide
Ocean currents and ocean circulation
- Oceans are the main heat redistribution engine on the planet, cooling the equator and warming the poles to make global climates more moderate.
- if channels between oceans close or open ocean circulation and therefore heat movement can be rearranged
Precession
Changes in our axis point, can cause seasonal timing to flip
Obliquity
Changes to the angle of earths tilt
Eccentricity
Changes in earths orbit from circle or oval
APOEM
Albedo
Precession
Obliquity
Eccentricity
Malankovitch
Lower albedo +
Positive solar forcing = warmer global climate
Higher Albedo
Negative solar forcing = cooler global climate
Pollen grains in sedimentary rocks
Different plant species thrive under different climates, so analyzing pollen in sediments helps reconstruct past vegetation and climate conditions.
Changes in rock types
Certain rocks form only under specific environmental conditions (e.g., glacial deposits indicate cold periods, while limestone suggests warmer, marine conditions).
Fossils and microfossils
The presence and types of fossils, especially microscopic ones, reflect past ecosystems and climate changes over time.
Isotopes ratios in rocks and deep-sea sediments
Variations in stable isotopes (like oxygen isotopes) serve as proxies for past temperatures and ice volumes, revealing climate fluctuations.
Human instrumental records
- 1607 invention of the thermometer
- 1800s widespread temps
- 1890s first weather services
- Widespread data has only been around 150-200 years
Ice cores
extraction of ice cores from kms deep in Antarctica and Greenland allow ice to be extracted , bubbles of ancient air from ice. The CO2 levels in the air act as a proxy data for global average temperatures.
Oxygen isotopes
18o;16o ratios are preserved in ice cores, marine sediments, mud, and cave formations. Therefore are a very useful tool to determine both recent acient climate changes.
Aboriginal heritage ground
ancient indigenous art sites preserve a record of fauna changes which indicates environemtnal change. This coastal site was much further inland during the last ice, when sea levels were lower. Emu prints here are much older than coastal bird pictures.
Dendrochronology
the science technique of dating events, environemtnal changes archaeological artefacts by using characteristics patterns of annual growth rings timber and tree trunks. The rings are thinner in years where its dry.
Speleothems
oxygen and carbon isotope ratios in speleothems can act as proxies for temperature, precipitation patterns, and even the presence or absence of soil and vegetation above the cave
Stalactites
Structures hanging from roof of cave
Stalagmite
Column rising from the floor of cave
Lace sediment samples
- layers of sediment build up on the bottom of the lake over time, recording what the environment was like when they formed
Thin layer: cooler climate
Thick layer; warmer climate
El Niño
a climate pattern in the tropical Pacific Ocean characterized by warmer-than-average sea surface temperatures
