4Th Grade Weathering, Weather And Atmosphere Study Guide

4th Grade Weather and Atmosphere Study Guide Test December 15, 2011

Weathering The natural process of breaking down rocks that causes them to break, change or crumble; slow change Glacier Flowing layer of ice; a river of ice; slow change Chemical Weathering that that causes the chemical make-up of a rock to change; slow change Weathering Volcano Molten rock from the earth that rises and escapes through the crust; quick change Erosion Wearing away of rock and soil by wind, water, waves and glaciers; slow change Hurricane Tropical system of rain and winds which circles around a center of low pressure and has sustained winds of at least 74mph; quick change Front The boundary between two unlike air masses Cold front The leading edge of a cold air mass; typically brings bad weather Warm front The leading edge of a warm air mass Lightning Electricity caused by friction between water droplets and ice crystals in a cloud Flooding High water levels caused by heavy rainfall over a short time; quick change Thunder Sound produced when lightning severely heats the air around it and causes the air to expand instantly Thunderstorm A storm with lightning Tornado Violently rotating column of air between a cloud and the earth Wind Air moving over the surface of the earth Atmosphere Blanket of gas that surrounds the earth Water Vapor A gas in Earth’s atmosphere Ice Cap A thick sheet of ice covering a large area of land Ground Water Stored in the cracks of underground rocks Water Soil Water Water that soaks into the ground Evaporation The process in which water particles change from a liquid to a gas Condensation The process in which water particles change from a gas to a liquid Precipitation Water in the atmosphere that falls to Earth as rain, snow, sleet or hail Barometer Instrument used to measure air pressure Anemometer Instrument used to measure wind speed Thermometer Instrument used to measure temperature Weather vane Instrument used to measure wind direction Hygrometer Instrument used to measure humidity Humidity Amount of moisture in the air Rain Gauge Instrument used to measure precipitation Earthquake Vibrations in the rock that makes up Earth’s crust; quick change

Know the water cycle: be able to draw, label and explain. Know what events cause slow changes and what events cause fast changes.