Educator Guide: Weather: Wind, Water and Temperature This document is a resource for teachers whose classes are participating in the Museum of Science’s Weather: Wind, Water and Temperature Traveling Program. The information in this document may be used as a classroom resource and/or as background information for the teacher concerning the subject of meteorology. Table of Contents: Vocabulary List……………………………………………………………………………2 Further Background Reading………………………………………………...………....5 Suggested Classroom Materials………………………………………………………..6 Activity Descriptions……………………………………………………………………...7 1 Vocabulary List This is a list of common weather terms that teachers may wish to be familiar with for the program. This list is also a suggestion of vocabulary for students participating in the Weather program to learn, though prior study of these words is not required for student participation. Albedo – the measurement of how much light is reflected or absorbed by a certain surface. This varies due to factors such as color, texture and surface area of the object (or area) in question. Anemometer – an instrument that measures the speed or force of the wind Atmosphere – thin gaseous layers insulating the Earth from extreme temperatures and blocking some of the ultraviolet radiation coming from the Sun. The Earth’s atmosphere is composed of a mixture of gases (nitrogen, oxygen, argon, carbon dioxide, trace amounts of other gases). Barometer – an instrument used for measuring air pressure Climate – the average weather conditions in an area over an extended period of time. Climate is different from weather, which is the present conditions of an area at a given time. Cloud – a visible collection of particles of water and/or ice crystals suspended in the air. Clouds form in the atmosphere as a result of the condensation of water vapor. Cold Front – the leading edge of an advancing cold air mass that is displacing the warmer air in its path. Typically with the passage of a cold front the temperature and humidity decrease, air pressure rises and the winds shift. Condensation Nuclei – small dust particles on which water vapor can condense to form clouds 2 Dew – water droplets appearing on outdoor objects in the morning or evening. If temperatures are low enough dew takes the form of ice, called frost. Dew Point – the temperature at which of a given parcel of moist air must be cooled to at constant pressure for the water vapor to condense into liquid water. Equator – the 0 degree latitude line that separates the Earth into the northern and southern hemispheres. The sun passes directly over the equator twice each year on the March and September equinoxes. On these dates the rays of the sun are perpendicular to the surface of the earth at the equator. Equinox – the point in time when the sun is directly over the equator. This causes day and night to be of approximately equal length all over the earth. Vernal (spring) equinox occurs about March 21st. Autumnal equinox occurs about September 22nd. Evaporation – a change from a liquid to a gas that occurs only at the surface of the liquid. Evaporation can happen at any temperature and is a slow process. This differs from boiling, which requires the liquid to be heated to its boiling point. Front – a boundary between cold and warm air masses High Pressure – when air pressure is higher than normal at ground level, often due to when cooler air sinking towards the ground. Humidity – the amount of water vapor in the air. Often confused with relative humidity, this is a ratio of the amount of water vapor in the air compared to how much water vapor the air under certain conditions could hold. Relative humidity is expressed as a percentage. Latitude – the location north or south of the equator Longitude – the location east or west in reference to the Prime Meridian Low Pressure – when air pressure is lower than normal at ground level, often due to warm air rising away from the ground 3 Meteorology – the study of the atmosphere, focusing on weather processes and short term forecasting. A meteorologist is a person who studies meteorology. Pressure – a force upon a surface by an object (solid, liquid or gaseous) Solstice – when the sun’s apparent position in the sky reaches its northernmost or southernmost extremes, about June 21st and December 21st each year Tropic of Cancer – the circle of latitude approximately 23.5 degrees north of the equator. The sun passes directly over the tropic of cancer during the June solstice. (The summer solstice in the Northern Hemisphere, the winter solstice in the Southern Hemisphere). Tropic of Capricorn – the circle of latitude approximately 23.5 degrees south of the equator. The sun passes directly over the tropic of cancer during the December solstice. (The winter solstice in the Northern Hemisphere, the summer solstice in the Southern Hemisphere). Warm Front – the leading edge of an advancing warm air mass that is replacing a relatively cooler, retreating, air mass. Typically with the passage of a warm front the temperature and humidity increase and the pressure rises. Water Cycle – the complex sequence through which water passes into atmosphere as water vapor, precipitates to earth in liquid or solid form and eventually returns to the atmosphere through evaporation. Water Vapor – water in its gaseous form Wind – the horizontal movement of air relative to the surface of the earth. Air moving from areas of high pressure to areas of low pressure is considered wind. 4 Further Background Reading This is a suggested reading list for teachers looking to improve their understanding of meteorology. Books The AMS Weather Book: The Ultimate Guide to America's Weather. Jack Williams. University Of Chicago Press. 2009. The Encyclopedia of Weather and Climate Change: A Complete Visual Guide. University of California Press. 2010. Links The Weather Channel glossary – http://www.weather.com/glossary/ NOAA: National Oceanic And Atmospheric Administration – http://www.noaa.gov/ 5 Classroom Materials Below are some suggestions for books and websites to help students increase their understanding of meteorology. Books The Best Book of Weather. Simon Adams. Kingfisher. 2008. Weather Detectives, The: Fun-filled facts, experiments, and activities for Kids. Gibbs Smith. 2004 Weather (DK Eyewitness Books). DK Children. 2007. Global Warming: The Threat of Earth's Changing Climate. Laurence Pringle. Chronicle Books. 2003. Links The Weather Channel Kids! – http://www.theweatherchannelkids.com/ Mish Michaels’s Weather Site – http://mishmichaelsweather.com/ EdHeads – http://www.edheads.org/activities/weather/ 6 Activity Descriptions See the “Documents” section on the website to download these activities. The Voyage of a Water Molecule We frequently describe the water cycle as a circle involving evaporation, condensation, precipitation and back to evaporation. While this is not incorrect it certainly doesn’t take into account the whole story. There are many forms of precipitation and much movement of water between precipitation and ultimately the evaporation back into the sky. This activity is meant to highlight all the various travels that a single water molecule can take, and is inspired by Project WET’s “The Incredible Journey”. Make a Cloud in a Bottle The science of clouds is very complicated and complex. A simple explanation is that as water vapor moves upwards through the atmosphere the air pressure decreases causing the temperature to decrease. This causes the water vapor to condense into tiny water droplets on dust particles that remain suspended in the air. If enough of these droplets condense we get a cloud. These conditions can be replicated right here at ground level. This activity shows the simplified mechanism of cloud formation. 7.