Using Weather Data Earth Science Unit II
What Is AIR? • Air is a mixture of colorless, odorless gases that surrounds the Earth. • 78 % Nitrogen • Plants need nitrogen to grown • 21% Oxygen • Living things need oxygen to survive • Plants give off oxygen • 1% Carbon dioxide • Plants take in carbon dioxide to make food. • Animals give of carbon dioxide2
What Is AIR? • The layer of gases that surrounds the Earth is called the atmosphere. • The atmosphere holds in heat from the sun keeping the Earth’s surface at a comfortable temperature. • The atmosphere protects living things from harmful rays given off by the sun.
What Is AIR? • Air takes up space and has weight. • The weight of the air that presses down is called air pressure. • A barometer is and instrument that measures air pressure.
What Is AIR? • The atmosphere has four layers: • Troposphere – ground to 6 miles. • This were Earth’s weather occurs. • Weather is the condition of the atmosphere at a certain place and time. • Stratosphere – 6 miles to 30 miles • Mesosphere – 30 miles to 50 miles • Thermosphere – 50 miles – 430 miles
What Is AIR? • Gases in the atmosphere keep Earth warm by letting in light and heat from the sun. • This natural heating of Earth is called the greenhouse effect. • Greenhouse effect is the processes by which heat from the dun builds up near the Earth’s surface and is trapped there by the atmosphere.
Summarize Air is made of nitrogen, oxygen, and other gases. Living things need air to survive. The atmosphere is a blanket of air that surrounds Earth. The air is thinner higher in the atmosphere. What is air? The atmosphere acts as a natural greenhouse that keeps Earth warm.
How does the water cycle affect weather? • Three states of water: • Solid (ice) • Liquid (water) • Gas (water vapor)
How does the water cycle affect weather? Liquid water + Heat Energy = Water vapor (gas) Evaporation Water vapor (gas) – Heat Energy = water (Liquid) Condensation Liquid water - Heat Energy = Ice (solid) Freezing (0C or 32F) Ice (solid) + Heat Energy = Water (Liquid) Melting
How does the water cycle affect weather? • The water cycle – is the movement of water into the air as water vapor and back to Earth’s surface as precipitation. • Precipitation is any form of water that falls from clouds to Earth’s surface • Clouds form when water vapor in the air condenses. A cloud that forms close to the ground is fog.
How does the water cycle affect weather? Water droplets attach to dust particles Gas to Liquid Condensation Cloud Formation Evaporation Liquid to gas Rain, snow, Sleet, hail Precipitation
How does the water cycle affect weather? • Clouds form when water vapor in the air condenses. A cloud that forms close to the ground is fog.
How does the water cycle affect weather? Cumulus: fluffy – fair weather Stratus: Low level –bring steady rain Cirrus: Thin,feathery clouds made of ice crystals – fair Cumulonimbus fluffy and tall – bring thunderstorms
How does the water cycle affect weather? • Forms of Precipitation • Rain – falling drops of water • Sleet – frozen rain • Snow – forms when the temperature in clouds is below freezing forming ice crystals known as snowflakes. • Hail - Rain freezes wind carries up higher in the cloud and more cumulates more ice when the hailstones are too heavy they fall
How does the water cycle affect weather? Rain Sleet Hail Snow
Summarize The water cycle is the movement of water into the air as water vapor and back to Earth as precipitation. Water exists in three states: solid ice, liquid water, and water vapor. How does the water cycle affect weather? Different types of clouds bring pleasant weather or precipitation.
What causes weather? • Weather involves all of the conditions of the atmosphere at a certain time and place..
What causes weather? • Weather Conditions include: • Temperature: How hot or cold the air is • A thermometer measures the temperature of the air • Humidity: The amount of water vapor in the atmosphere • A rain gauge measures the amount of precipitation that has fallen. • Wind speed and direction: The movement of air • An anemometer measures wind speed • A weather vane and wind sock measure wind direction • Air pressure: The weight of air as it pressed down on Earth’s surface. • A barometer measures air pressure.
What causes weather? Thermometer Anemometer Rain Gauge Barometer
What causes weather? • Wind is the movement of air. • Air flows from areas of high pressure to areas of low pressure. • During the day, cool ocean breezes move toward the land. • At night, cool air above the land moves toward the ocean.
What causes weather? • An air mass is a large body of air that about the same temperature, air pressure, and moisture throughout. • Air masses are described by two conditions • Warm or Cold • Moist or Dry
What causes weather? • Air masses that form near the equator are usually warm. • Air masses that form near the poles are usually cold. • Air masses that form over the oceans are usually moist. • Most changes in weather occur when one air mass moves into an area and pushes out another air mass.
What causes weather? • The rotation of the Earth they bump into each other. • The causes the air masses to move. • As they move, place where two air masses meet is called a front. • Most storms and precipitation take place along fronts.
What causes weather? • Two types of fronts: • Cold Front: Cold air mass moves under a warm air mass, pushing it up. • Thunderstorms often strike along cold fronts. • Warm Front: Warm air mass moves over a cold air mass. • Layers of gray clouds and steady precipitation are common along warm fronts.
What causes weather? Cold Front Warm Front
What causes weather? • A meteorologist is a scientists who studies weather. • Studying weather involves: • Measuring conditions near Earth’s surface and high in the atmosphere. • Scientist gather data from many sources including: • Radar • Satellites • Using data collected to: • Identify kinds of air masses over an area • Predict what kind of front will form and where it will move to. • Produce weather maps. • Make forecasts – a prediction of what the weather will be for a particular day, week, or longer. • www.weather.com
What causes weather? • Hurricanes, tornadoes, thunderstorms, and snowstorms are examples of severe, dangerous weather. • Meteorologists study storms using satellites in space and weather instruments on the ground. • Meteorologists issue warnings when severe weather approaches which can save lives.
Summarize Earth’s surface heats unevenly, causing air masses to form. Fronts form where air masses collide. Weather factors include temperature moisture, air pressure, and wind. What causes weather? Meteorologists gather and study weather data. They use this data to make forecasts and track severe weather.