Weather Science SOL: 2.6 Miss Ahrens Second Grade What is weather? Weather is how hot or cold it is outside. It can change everyday. Weather can be sunny or not. The weather changes because of the changes in the atmosphere. The atmosphere is the area around the Earth, the sky. It is a mixture of gases. What is the Water Cycle? Evaporation-Water from lakes, oceans, puddles and rivers is dried up by the sun causing water vapor to rise in the sky. Condensation-Water vapor condenses (forms) into clouds (and sometimes fog). Precipitation-When clouds become too heavy with water it falls to the ground in the form of rain, hail, sleet, or snow. Water and the States of Matter Liquid--Water is a liquid. Rain is a liquid. Solid--When frozen, water is a solid. Ice, snow, sleet, and hail are solids. Frost is frozen dew. Gas--Water vapor is a gas that condenses into clouds. Fog is also made from water vapor floating in the air. (Like a low cloud). Dew is water vapor condensed on the ground. Types of Weather Cloudy Cold Cool Hail Hot Lightning Rainy Sleeting Snowy Stormy Sunny Temperature Thunder Warm Windy Temperature Temperature tells us how hot or cold it is outside. It is measured by a thermometer. Thermometers measure the temperature in degrees. There are two ways that temperature can be measured: Fahrenheit and Celsius degrees. Precipitation: Rain and Snow Water that falls from the sky. Rain—Drops of water that fall from the sky. Snow—Ice Crystals that fall from the sky. Hail—Ice that falls from the sky during thunderstorms or tornadoes. Sleet—An icy mixture of rain and snow. Clouds Clouds are formed by evaporated water. Clouds are condensed water vapor. There are different types of clouds: Altocumulus, Cirrus, Cirrostratus, Cirrocumulus, Cumulonimbus, Cumulus, Nimbostratus, Stratocumulus, and Stratus. Wind Wind is air that is moving. It is caused by warm air rising and cool air moving under it. Wind is caused by hot and cold air pushing together. Lightning Electric sparks from the sky. Sparks from a rain cloud to the Earth. These sparks heat the air up and we see the flash of heat (lightning). Lightning happens in thunderstorms. There are different kinds of lightening: fork lightning, ribbon lightning, and bead or chain lightning. Thunder Thunder is caused by lightning. Lightning heats the air up so hot that it makes the hot air bump into the cold air. This bumping sound is thunder. Types of Extreme Weather Blizzard Drought Flood Hurricane Thunderstorm Tornado Blizzard Blizzards are bad snow storms. They have lots of wind. The wind blows the snow and makes it hard to see. Blizzards have very cold temperatures. There is a lot of snow in a blizzard. We will miss school in a blizzard. Drought A drought is when there is no rain for a long time. All the plants dry up and usually die. The ground becomes hard and cracked. Most animals have to go somewhere else to find water. Flood Floods happen when there is too much rain for the ground to soak up. Sometimes rivers and lakes overflow causing floods. Sometimes floods happen when there is a lot of snow that melts. A flood is where there is a large amount of water that covers dry land. Hurricane A strong spinning storm. They begin over the ocean and run into the land. Hurricanes have strong winds that destroy homes. They have lots of rain and cause flooding. The rain pushes the ocean water on the land and causes more flooding. Thunderstorm These storms have lots of lightning. They have lots of loud thunder. They have howling winds. Some thunderstorms have a lot of rain. Some storms do not have rain. Thunderstorms have dark clouds. Tornado Tornadoes have powerful winds. The winds make a spinning funnel cloud. The funnel clouds destroy homes and buildings. Some are strong enough to pick up cars. They have dark clouds. There is rain and sometimes hail. Measuring Weather Barometer—Instrument used for measuring air pressure. Rain Gauge—Instrument that tells how much rain has fallen. Thermometer—Instrument used to measure temperature. Weather Vane—Instrument used to tell which way the wind blows. Weather Data Data means information. Meteorologist—A person who studies weather. Data is very useful for predicting and determining weather patterns and what the weather will be. Data is collected and recorded using different instruments.