Untitled Flashcards Set

Earth’s structure:

Lithosphere- made up of mantle and crust, where tectonic plates are found

Crust- outermost layer of lithosphere, earth’s surface

Asthenosphere: Solid flexible outer layer of the mantle

Mantle- Layer of liquid magma surrounding core

Inner Core- Dense mass of solid metals, innermost layer

Tectonic plates move because of convection currents in the mantle

Convection cycles- magma heated by the earth's core rises towards the lithosphere, cools, expands, solidifies, creates mid ocean ridges and seafloor spreading (divergent)

Spreading magma forces oceanic plates to subduct under continental plates, forces magma up and creates small coastal mountains and land volcanoes

Divergent boundaries- earthquakes, ocean ridges, rift valleys, sea floor spreading

Convergent boundaries:

Oceanic + continental ocean plate subducts, possible volcanic arc formation, trench, earthquakes, tsunamis

Oceanic Oceanic- older, colder, denser plate subducts, beneath the younger plate, earthquakes, island arc, trench

Continental + Continental- mountain range forms, earthquakes

Transform boundaries

Plates slide past each other on opposite directions, creates a fault

Earthquakes occur when rough edges of plates get stuck on each other

Pressure builds as plates keep sliding, but edges stay stuck, leading to release that shakes the lithosphere

Hotspots

Mantle plumes drive hot liquid rocks upward towards earth's surface, occur within plates

Troposphere, weather occurs here, most dense, most gas molecules found here, ozone harmful to humans, 0-16 KM

Stratosphere: Less dense, thickest O3 layer, 16-60 Km

Ozone layer: stratospheric ozone main function is to absorb UV-B and UV-C

Mesosphere: 60-80 km, meteors burn up here

Thermosphere: Absorbs harmful x-rays and harmful UV radiation 80-840 km

Exosphere: 5th layer, merges with space

Earth’s tilt and orbit around the sun

Earth tilted at 23.5 degree angle

The part of earth tilted toward the sun will experience summer, part tilted away will experience winter

Equator receives year round direct sunlight, stable warm climates

Sun's rays hit earth at increasing angles, which is why temp decreases with latitude

Atmospheric Convection currents

Air is warmed by the radiation of the sun and becomes less dense with the lower pressure so it rises

As air cools, it cannot hold onto moisture as easily and so it precipitates

At high altitudes, the air cools as the gasses expand and are moved by the warm air that continues to rise

Cool air falls to the ground and wars as it gets closer to the ground

Air flows back to point of origin due to pressure systems, causing large scale convection currents called cells

Coriolis effect causes objects to be deflected to the right in the northern and the left in the southern hemisphere

Oceans are driven by wind, ocean gyres are the 5 massive circular current systems

Upwellings (upward movements of ocean water) are driven by wind, push warm water away from the coast and replace it with deep cold ocean water

Gyres take place along western coasts

La nina and El nino are due to changes in upwelling and winds changing

El nino

Trade winds sometimes slow down and even recourse direction

Warm water is pushed towards the coast, no upwelling

Weather is Rainy in South America, droughts and wildfires in Australia, bad for economy, ecosystems

La Nina

Opposite of El Nino, extra strong tropical trade winds blowing east to west, more upwelling, cold and dry in South American and wet in Australia, good for economy, ecosystems

Rainshadow effect

Elevated terrains act as a lifting mechanism for air

Warm moist air cools as it rises and cannot hold on to air as easily, leading to rain

Leeward side has arid conditions

Humus: main organic part of soil, leaves, dead animals, waste

Soil nutrients: ammonium, phosphorus, potassium, nitrates

Soil is created by weathering, parent material broken into smaller pieces, breakdown of organic matter adds humus, erosion deposits soil particles

Soil horizons

O horizon, layer of organic matter on top of soil

A horizon, topsoil, layer of humus and minerals

B horizon: subsoil, lighter layer below topsoil, made mostly of minerals with little to no organic matter, contains some nutrients

C horizon: last weathered soil that is closest to the parent material

Soil textures

Clay (smallest) 0.002 mm

Silt: 0.05 -0.002mm

Sand: 2 to 0.05mm

Porosity- pore space per volume

Permeability- relative ease in which water and air pass through

Water holding capacity: more porosity or permeability means less holding capacity