past climeats Flashcards
Snowball Earth
The whole earth was glacia
Ice house earth
A period in Earth’s history characterized by cooler global temperatures, lower greenhouse gas concentrations, and the presence of extensive ice sheets.
Isotope
Variants of a chemical element that have the same number of protons but a different number of neutrons, important in geology for dating rocks and tracing environmental changes
Greenhouse Effect
The warming of Earth’s surface caused by the trapping of heat from the Sun by greenhouse gases like carbon dioxide, methane, and water vapor in the atmosphere.
Albedo
The reflectivity of a surface, where higher albedo (e.g., ice and snow) reflects more solar radiation and lower albedo (e.g., oceans or forests) absorbs more heat, influencing global temperatures.
Insolation
The amount of solar radiation reaching the Earth’s surface, which varies based on location, time of year, and atmospheric conditions, affecting climate and temperature patterns.
Dropstone
Large rocks that are transported by glaciers or icebergs and dropped into marine sediments as the ice melts, often used as evidence for glaciation.
Ice Sheet
A large, continent-sized mass of glacier ice that covers significant portions of Earth’s land surface, such as the Antarctic and Greenland ice sheets.
Glacier
A slow-moving river of ice formed by the accumulation and compaction of snow on mountains or polar regions, crucial to Earth’s hydrological and climate systems.
Sea Ice
Frozen seawater that forms, expands, and melts in the ocean, distinct from icebergs, glaciers, and ice sheets, and plays a critical role in Earth’s climate by reflecting sunlight and insulating the ocean.
Ocean Current
Large-scale movement of water within the oceans, driven by wind, salinity, and temperature differences, important for regulating global climate by transporting heat.
Thermohaline Circulation
The global “conveyor belt” of ocean water driven by differences in temperature (thermal) and salinity (haline), essential for distributing heat across the planet and regulating climate.
Glacial Till/Boulder Clay
Unsorted sediment deposited directly by a glacier, consisting of a mix of clay, silt, sand, gravel, and boulders, often used as evidence of past glaciations.
Palaeomagnetism
The study of the record of Earth’s magnetic field preserved in rocks, sediments, or archaeological materials, used to understand plate tectonics and the movement of continents.
Cap Carbonates
Layers of carbonate rocks that form on top of glacial deposits, typically following a “Snowball Earth” event, representing a return to warmer, ice-free conditions.
Foraminifera
Marine microorganisms with calcareous shells, whose fossilized remains are used as bio-indicators for paleoclimate reconstructions due to their sensitivity to environmental conditions.
Coccolith
Tiny, calcite-producing algae (coccolithophores) that contribute to marine sediments, such as chalk, and provide key data for studying ancient climates.
Radiolarian
Single-celled marine organisms with siliceous skeletons, which, when fossilized, help reconstruct past oceanic conditions and sedimentary environments.
Microfossil
Tiny fossils, often of planktonic organisms like foraminifera, diatoms, or pollen, used in biostratigraphy and paleoenvironmental reconstructions.
Pollen
Microscopic grains released by plants for reproduction, preserved in sediments, and used as proxy data for reconstructing past vegetation and climates
Spores
Reproductive cells produced by fungi, algae, and some plants, which can be preserved in sediments and serve as indicators of past environmental conditions.
Zone Fossil
Fossils of organisms that were widespread but only existed for a short geological time period, useful for dating and correlating rock strata.
Palaeoclimate
The study of past climates on Earth, inferred from geological evidence like ice cores, tree rings, and sediment layers, often using proxies.
Proxy Data
Indirect evidence (e.g., ice cores, tree rings, sediment layers) used to infer past environmental conditions, since direct measurements are unavailable for ancient climates.
