Unit at a Glance Chapter 11: The Water Cycle Standards S6E3: Students will recognize the significant role of water in Earth's processes. a. Explain that a large portion of the Earth's surface is water, consisting of oceans, rivers, lakes, underground water, and ice. b. Relate various atmospheric conditions to stages of the water cycle. Unit Vocabulary Water Cycle: the continuous movement of water from the ocean, to the atmosphere, to the land, and back to the ocean. Evaporation: a process that takes place when water on the Earth’s surface gets heated up and gains energy from the sun and turns into water vapor (a gas). Humidity: the amount of water vapor in the air. Condensation: a process that takes place when water vapor cools and changes back into liquid water droplets that form clouds in the atmosphere. Cloud: a collection of small water droplets OR ice crystals suspended in the air which forms when condensations occurs. Cumulus Cloud: puffy, white clouds that tend to have flat bottoms. Stratus Cloud: flat-looking clouds that form in layers. Cirrus Cloud: thin, feathery, white clouds that form at high altitudes from ice crystals. Precipitation: water, in solid or liquid form, that falls from the air to Earth, (ex. rain, snow, sleet, or hail.) Rain: water that falls from the clouds as gravity pulls condensed water droplets back to Earth. The most common type of precipitation. Snow: a type of precipitation that forms when temperatures are so low that water vapor condenses directly into a solid. Sleet: a type of precipitation that forms when rain falls through a layer of freezing air. Hail: a type of precipitation that forms during severe storms and consists of balls or lumps of ice. Percolation: the downward movement of water through pores and other spaces in the soil due to gravity. Water soaking into the ground to become groundwater. Runoff: precipitation that flows over land and into streams, rivers, and lakes. Watershed: any area of land that is drained by a river system. Divide: an area of higher land on the edges of a watershed that divides up drainage basins. Unit at a Glance Channel: the path (think ditch) that a stream follows. Tributary: a stream that flows into a lake or larger stream. Erosion: the process by which wind, water, ice, or gravity transports soil and sediment from one location to another. Load: the materials that are carried by a stream. Deposition: the process in which materials carried by wind, water, ice, or gravity are dropped and come to rest. Alluvial Fan: a fan-shaped mass of material deposited by a stream when a stream flows onto dry land. Delta: a fan-shaped mass of material deposited at the mouth of a stream. Floodplain: an area along a river that forms from sediments deposited when the river overflows its banks. Water Table: the upper level of underground water. Recharge Zone: an area in which water travels downward to become part of an aquifer. Permeability: the measure of whether water can flow through rock or not. Porosity: the number of open spaces between rock particles in a rock layer for water to fill in. Artesian Spring: a natural spring whose water flows out of the ground through a cap rock. Essential Questions 1. What are the steps of the water cycle? 2. How do rivers erode the surface of the Earth? 3. What are the three "ages" of rivers and their characteristics? 4. What is groundwater and how does it get there?