Ch. 3 Key Terms Flashcards
Geosphere
The solid part of the Earth that consists of all rock, as well as the soils and loose rocks on Earth’s surface.
Hydrosphere
Makes up all of the water on or near Earth’s surface.
Crust
The thin layer of Earth composed almost entirely of light elements. The crust makes up less than 1 percent of the Earth’s mass.
Mantle
The layer beneath the crust that makes up 68 percent of the Earth’s mass. The mantle is approximately 2,900 km thick and is made up of rocks of medium density.
Core
The innermost layer of the Earth. The radius of the core s approximately 3,400 km and is composed of elements with the greatest density.
Lithosphere
The outermost layer of the Earth. A cool rigid layer that is 15 km to 300 km thick. That includes the crust and upper part of the mantle.
Asthenosphere
The layer beneath the lithosphere. A solid layer of the mantle that is made of rock that flows very slowly and allowed tectonic plates to move above it.
Tectonic Plate
The lithosphere is made up of tectonic plates that glide across the asthenosphere. The continents are located on these tectonic plates.
Chemical Weathering
Wears down rocks, making them smoother over time.
Erosion
Transports the materials of weathered rocks elsewhere.
Atmosphere
The mixture of gasses that surround Earth. Nitrogen, oxygen, carbon dioxide, and other gasses are a part of this mixture.
Troposphere
The atmospheric layer nearest to Earth,s surface. Extends to about 18 km above Earth’s surface. Almost all the weather occurs in this area.
Stratosphere
The area above the troposphere. Extends from 18 km to about 50 km above the Earth.
Ozone
The Ozone layer within the stratosphere limits the amount of harmful UV rays that reach Earth.
Radiation
The transfer of energy by electromagnetic waves. When you stand in front of a fire, the warmth you feel is being transmitted by radiation.
Conduction
The transfer of energy in the form of heat by direct physical contact.
Convection
The transfer of energy that takes place when variations in temperature move the matter making up air.
Greenhouse Effect
The process in which greenhouse gases absorb and reradiate infrared radiation near the Earth. Without this, the Earth would be too cold to sustain life.
Water Cycle
The continuous movement of water into the air, onto land, and then back to water sources.
Evaporation
The process by which liquid water is heated by the sun and then rises into the atmosphere as water vapor.
Condensation
Water vapor forms water droplets on dust particles. These water droplets form clouds, in which the water droplets collide, stick together and create heavier larger droplets. These droplets fall from clouds as rain.
Precipitation
Water droplets falling from the sky. May also take the form of snow, sleet, or hail.
Salinity
The concentration of all the dissolved salts on the ocean.
Fresh Water
Most of the Earth’s water is saltwater but a little more than 3 percent of it is freshwater meaning that there is no salt in the water. Most of the freshwater in the world is locked up in polar ice caps and glaciers.
