Syllabus bits I do not get Flashcards
(8 cards)
What is the global distribution and size of major stores of water in the lithosphere, hydrosphere, cryosphere, and atmosphere?
Hydrosphere (oceans, etc.): 96.5%
Cryosphere (ice caps, glaciers): 1.7% (60% of Earth’s fresh water)
Groundwater (lithosphere): 1.7% (30% of Earth’s fresh water) - Aquifers
Lakes and rivers: 0.01%
Atmosphere: 0.001%
Major stores of water are categorized by their location and size, with the hydrosphere being the largest store.
What are the three main causes of precipitation?
Convectional rainfall: Warm, moist air rises, cools, condenses, and falls.
Frontal rainfall: Warm air meets cold air, the warm air rises, cools, and condenses.
Orographic rainfall: Moist air rises over mountains, cools, and condenses.
These processes lead to different types of rainfall based on atmospheric conditions.
What is the global distribution and size of major stores of carbon in the lithosphere, hydrosphere, cryosphere, biosphere, and atmosphere?
Lithosphere: ~99.9% (mainly sedimentary rocks and fossil fuels 0.004%)
Hydrosphere: ~ 0.04% (carbon dissolved in oceans, rivers and lakes)
Biosphere: ~ 0.004% (plants, animals, soils)
Atmosphere: ~ 0.001% (as CO₂ and other gases)
Cryosphere: Very small/negligible (trapped in permafrost)
Carbon is stored in various forms across different spheres, with the lithosphere being the largest reservoir.
How does the carbon cycle impact land, ocean, atmosphere, and global climate?
Land: Soils and vegetation store carbon; human activities reduce storage.
Oceans: Oceans absorb 25% of CO₂, but increased CO₂ causes Ocean acidification bleaching choral. Also causes Thermal expansion.
Atmosphere: Rising CO₂ leads to global warming and climate change.
Global Climate Impact: Disruptions in the carbon cycle worsen climate change, with feedback loops like permafrost melting releasing methane.
The carbon cycle plays a crucial role in regulating Earth’s climate and ecosystems.
What are positive and negative feedback loops at the coast?
Positive feedback: Coastal erosion removes sediment, reducing beach material, leading to more erosion.
Negative feedback: Eroded material forms beaches, which absorb wave energy, reducing further erosion.
Feedback loops can either exacerbate or mitigate coastal erosion effects.
What is the structure of the Earth and its internal energy sources?
Core: Generates heat through radioactive decay and formation energy.
Mantle: Semi-molten, transfers heat through convection.
Crust: Thin outer layer split into tectonic plates.
Internal energy source: Radioactive decay drives convection currents in the mantle.
Understanding Earth’s structure is essential for studying geological processes.
What is the plate tectonic theory of crustal evolution?
Tectonic Plates: Large sections of Earth’s crust and upper mantle that float on the asthenosphere.
Plate Movement: Driven by internal heat, causing plates to move at divergent, convergent, and transform boundaries.
Plate tectonics is a fundamental theory explaining the movement of Earth’s lithosphere.
What are the mechanisms that drive plate movement?
Convection currents: Heat causes molten rock to move in circular patterns, dragging plates.
Ridge push: Newly formed, hot, buoyant rock at mid-ocean ridges pushes older rock apart. (Constructive boundaries).
Gravitational sliding: High elevation at ridges causes rock to slide down and push plates outward. (Constructive boundaries)
Slab pull: Subducting plates pull the rest of the plate due to gravity. (Destructive boundary).
Sea-floor spreading: New crust forms at mid-ocean ridges, confirming plate movement with showing magnetic stripes. (Constructive boundary)
These mechanisms explain how tectonic plates interact and change Earth’s surface.
