Evaporation - Water evaporates (changes from a liquid to a gas) into water vapor due to heat from the Sun.

Transcription

1 Erin Kathryn 2016

2 Weather is the conditions of Earth s atmosphere at a certain time and place. For example, sunshine, rain, hurricanes, and storms are all examples of weather. Weather is different at different places around the world.

3 The atmosphere is the layers of air that surround Earth s surface. Earth s atmosphere has 4 layers: troposphere, stratosphere, mesosphere and thermosphere. Weather occurs in the first layer of the atmosphere, the troposphere.

4 The water cycle is the movement of water into the air as water vapor and back to Earth s surface as precipitation. The water on Earth is constantly changing from one form to another in a continuous cycle that occurs over and over again.

5 Evaporation - Water evaporates (changes from a liquid to a gas) into water vapor due to heat from the Sun. Condensation Water condenses (changes from a gas into a liquid) into water droplets. These water droplets form clouds.

6 Different types of clouds bring various types of weather. Cloud Description Picture stratus cumulus cirrus Low-level cloud that forms in layers and usually brings rain Fluffy clouds that are flat on the bottom and usually mean fair weather Thin clouds that look like feathers and form high in the sky; usually bring fair weather cumulonimbus Tall clouds that bring thunderstorms

7 Different types of clouds bring various types of weather. Cloud Description Picture fog Cloud that forms close to the ground altocumulus Small, white, puffy, middle level cloud stratocumulus Low puffy, gray clouds that can sometimes produce rain cirrocumulus High clouds that look like tiny cotton balls bunched together altostratus Dark gray covering cloud that usually brings rain

8 Precipitation- When clouds become too heavy, the water droplets fall to Earth s surface in the form of rain, snow, sleet, or hail. Collection Precipitation collects in rivers, streams, oceans, and lakes allowing it to be evaporated and begin the water cycle again.

9 rain Falling drops of liquid water snow Falls when the temperature in the cloud is below freezing (32 F) sleet hail Rain that freezes as it falls to Earth s surface Forms when drops of rain freeze in the cloud and are carried higher into the cloud freezing over and over before falling to Earth s surface

10 Runoff- Precipitation that flows downhill on Earth s surface to rivers, streams, lakes, and oceans is called runoff. Infiltration Some precipitation soaks into the ground. This is called infiltration or groundwater.

11 Weather conditions include temperature, humidity, wind, and air pressure. Temperature how hot or cold the air is Humidity the amount of water vapor in the air Wind the movement of air Air pressure the weight of air as it presses down on Earth.

12 Weather conditions can be measured using various weather instruments. thermometer rain gauge Measures the temperature of the air Collects and measures the amount of precipitation that has fallen in an area

13 Weather conditions can be measured using various weather instruments. barometer anemometer Wind vane Measures air pressure Measures the speed of the wind Measures the direction of the wind

14 An air mass is a large body of air that has about the same temperature, air pressure, and moisture. Air masses are either warm or cold and either moist or dry.

15 Warm air masses usually form near warm places. Cold air masses usually form near cold places. Moist air masses usually form over oceans. Dry air masses usually form over land. Most changes in weather happen when one air mass moves into a place and pushes out another air mass.

16 The place where two air masses meet is called a front. Weather can change suddenly when a front moves across an area. Many storms and precipitation take place along fronts.

17 When a cold air mass meets a warm air mass a cold front forms. The cold air moves under the warm air, pushing it up. The warm air rises, clouds and precipitation occur. Cold fronts often bring thunderstorms. Cold front symbol on a weather map

18 A warm front forms when a warm air mass pushes into a cold air mass. The warm air slowly moves up and over the cold air forming layers of gray clouds and steady precipitation. Warm front symbol on a weather map

19 Meteorology is the study of weather. This involves the measuring of conditions near Earth s surface and high in the atmosphere. Meteorologists identify air masses and fronts. They also predict where they will move.

20 These predictions help meteorologists create a weather map. Weather maps are used to help forecast the weather. Weather maps use symbols to show the location of fronts and precipitation. A forecast is a prediction of what the weather will be for a certain day, week, or longer period of time.

21 Severe weather includes hurricanes, tornadoes, and snowstorms. Meteorologists study and forecast storms using various tools. Forecasters can give weather warnings when severe weather is likely to move into an area. Warning give people time to prepare or leave an area. Erin Kathryn 2016

22 Climate is the usual weather conditions of a place over an extended amount of time. Climate has a lot to do with the kinds of plants and animals that can live and survive there.

23 How much sunlight an area gets, oceans or large bodies of water, altitude, and mountains are all factors that affect climate. Scientists learn about climate by looking at tree rings in old fossils and evaluating core samples of ice to see how the layers of fossil and ice have changed over time.