Weather Systems In this presentation you will: explore the impact of the Sun’s energy on Earth’s weather systems Next >

Introduction The Sun is the major source of energy on Earth. Without heat and light from the Sun, there could be no life on Earth. As well as supporting life, the Sun also provides the energy for creating wind and ocean currents. Next >

Transfer of Energy The Sun transfers energy when it transmits light and heat. There are three ways in which energy could be transmitted: Radiation – transfer by waves or rays. If you lay on the beach you feel the heat rays from the Sun. Next >

Transfer of Energy Conduction – transfer by molecules bumping into each other. Touching a hot surface will transfer heat from the surface to your hand. Convection – transfer by flow of material. Hot air moves toward colder air and vice versa. Next >

Transfer of Energy Through Space Space is a vacuum. Energy cannot travel by conduction or convection through a vacuum. Energy is transferred from the Sun to the Earth by radiation, because radiation can pass through a vacuum. radiation Next >

Transfer of Energy Through Space Once the Sun’s energy reaches Earth, it travels through different materials by conduction, convection, and radiation. convection conduction It can be absorbed by any material it passes through, raising the temperature of the material as it does. radiation Next >

Wind As the Sun radiates heat to the Earth, different surfaces absorb the heat energy in different ways. hot side cool side The changing position of the Earth in relation to the Sun means that different parts of the Earth receive more heat energy than others, depending on their location, the time of day, and the time of year. As a result, the Earth’s surface is heated unevenly. Next >

Wind A natural phenomenon of thermal equilibrium makes air of different temperatures try to equalize (balance). Hot air moves to try and warm the area taken up by cooler air, and cold air moves to the area taken up by warmer air. Next >

Wind In scientific terms this movement is known as Convection Current. In everyday terms this air movement is wind! The same principle of convection is used to heat homes and make hot air balloons rise. Next >

Wind – Jet Streams Large differences in temperature will cause the air to move faster. Stratosphere Troposphere Mesosphere This occurs high up in the atmosphere where the troposphere meets the stratosphere. Polar jet stream Subtropical jet stream These fast winds are known as jet streams and they continuously circle the Earth. Subtropical jet stream Polar jet stream Next >

Thermal image of the Gulf Stream off the coast of the USA Ocean Currents In a similar way, radiation from the Sun heats the oceans, creating convection currents in the water. Warm water from the Equator moves toward the north and south poles, where the water is much colder. Cold water from the poles moves toward the Equator. Thermal image of the Gulf Stream off the coast of the USA Next >

Ocean Currents, Weather and Climate These convection currents create warm and cold ‘streams’ that influence the weather and climate of the land they pass. Next >

The Oceans and Climate A warm current can cause land that it passes to have a temperate (mild) climate when it would otherwise be cold. For example, the United Kingdom is as far north as Canada, so you may expect the two places to be equally cold in winter. cb6379 Canada the_junes UK Canada UK North Atlantic Current However, the warming North Atlantic current, passes the UK, causing it to have much milder winter weather than Canada. Next >

The Oceans and Climate Ocean water has a higher specific heat capacity than land. ° C temperature inland temperature at sea Specific heat capacity is the amount of energy needed to raise the temperature of 1 kg of a substance by 1 °C. Since salt water has a higher specific heat capacity than land, ocean temperatures increase and decrease more slowly than land temperatures. The high specific heat capacity of ocean water causes coastal land to have a milder climate than inland areas. Next >

Water Cycle The heating of the ocean plays a part of the water cycle – the movement of all water on Earth. The water turns into water vapor, evaporates into gas, cools and condenses back into drops of water and forms clouds. clouds rain Next >

The Oceans and Climate When moist air condenses over the oceans, it could also lead to the formation of tropical storms. These storms are violent and potentially devastating. Depending on where the storm is in the world will determine what it is called. Hurricanes - Atlantic Ocean, Gulf of Mexico and the Eastern Pacific Ocean Cyclones - Indian Ocean, Bay of Bengal, Australia Typhoons - Western Pacific Ocean Next >

The Oceans and Climate Changes in the ocean can cause dramatic changes to climate and weather patterns on a global scale. For example, a small change in ocean temperature can lead to an increased number of tropical storms. Such changes can be brought about by natural processes or man-made problems. For example, many scientists believe that global warming is caused by human activities. Next >

Weather The properties of the atmosphere, such as temperature, water content (humidity) and air pressure, largely determine the weather. Scientists are able to predict the weather by observing and measuring these properties. Weather often occurs as a result of differences in temperature and pressure from one place to another. Next >

Wind When there is a difference in pressure between two air masses, air moves from the area of higher pressure to the area of lower pressure, creating wind. Sunlight Low pressure High Wind This movement continues until the pressures in the two areas become equal. Wind varies in intensity and strength from a gentle breeze to a powerful and destructive storm, such as a hurricane or tornado. Next >

Local Weather Local weather is influenced by atmospheric and surface conditions in the local area. For example, tall mountains can ‘block’ rain by forcing clouds higher into the atmosphere. Wind Rainy Dry This can be seen along the Rocky Mountains in the western United States. Next >

Local Weather Winds blow across the US from the west, bringing rainy weather to northern states west of the Rockies. When clouds reach the Rockies, they are forced up, causing rain to fall on the western slopes, while very little rain falls on the plains to the east. Local weather is also influenced by global atmospheric conditions. Wind Changes that occur in the atmosphere thousands of miles away can affect the weather. Rainy Dry Next >

Weather Maps Weather maps can be used to show how changes in atmospheric conditions can influence local weather. Isobars Air pressure is shown on maps using isobars; lines joining locations of equal pressure. Next >

Weather Maps – Low Pressure Areas of low pressure indicate warm air rising. These areas usually bring cloudy weather, and if there is enough water vapor, precipitation. Low pressure area Next >

Weather Maps – High Pressure Areas of high pressure indicate cold air sinking. These areas usually bring clear skies and sunny weather. High pressure area Next >

Weather Fronts A weather front is simply a boundary between air masses. There are 4 types: cold front – when cold air moves towards, and replaces, warmer air. This is a rapid movement of air that causes thunder storms and tornados. warm front – when warm air moves towards colder air; usually brings rain. The movement of warm fronts is slower. Next >

Weather Fronts occluded front – when a cold front overtakes a warm front, pushing the warm air up. stationary front – neither front is advancing. Usually brings periods of cloudy and wet weather. Next >

Question 1 Which of the following transfers energy by flow of material? A) Convection B) Conduction C) Radiation Next >

Question 1 Which of the following transfers energy by flow of material? A) Convection B) Conduction C) Radiation Next >

Question 2 ‘Energy can travel by conduction and convection through space.’ Is this statement true or false? Answer True or False. Next >

Question 2 ‘Energy can travel by conduction and convection through space.’ Is this statement true or false? False Next >

Question 3 What method is used in transferring energy from the Sun to Earth? A) Convection B) Conduction C) Radiation Next >

Question 3 What method is used in transferring energy from the Sun to Earth? A) Convection B) Conduction C) Radiation Next >

Question 4 Convection currents are responsible for what? A) Only wind B) Only ocean currents C) Both wind and ocean currents D) Neither wind nor ocean currents Next >

Question 4 Convection currents are responsible for what? A) Only wind B) Only ocean currents C) Both wind and ocean currents D) Neither wind nor ocean currents Next >

Question 5 'A warm current can cause the land it passes to have a temperate climate.' Is this statement true or false? Answer True or False. Next >

Question 5 'A warm current can cause the land it passes to have a temperate climate.' Is this statement true or false? True Next >

Question 6 What impact do oceans have on the formation of weather systems on a global scale? A) They can produce tropical storms such as hurricanes and typhoons B) They can change the climate of cold locations to be temperate C) They can cause differences in temperatures between coastal and inland regions D) All of the above Next >

Question 6 What impact do oceans have on the formation of weather systems on a global scale? A) They can produce tropical storms such as hurricanes and typhoons B) They can change the climate of cold locations to be temperate C) They can cause differences in temperatures between coastal and inland regions D) All of the above Next >

Question 7 "Wind can occur when air moves from an area of high pressure to an area of lower pressure." Is this statement true or false? Answer True or False. Next >

Question 7 "Wind can occur when air moves from an area of high pressure to an area of lower pressure." Is this statement true or false? True Next >

Question 8 What type of air pressure brings cloudy weather and rain? A) Wind B) Low Pressure C) High Pressure D) Isobar Next >

Question 8 What type of air pressure brings cloudy weather and rain? A) Wind B) Low Pressure C) High Pressure D) Isobar Next >

Question 9 What type of weather front brings thunderstorms and tornados? A) Occluded Front B) Stationary Front C) Cold Front D) Warm Front Next >

Question 9 What type of weather front brings thunderstorms and tornados? A) Occluded Front B) Stationary Front C) Cold Front D) Warm Front Next >

Question 10 What type of weather will the front shown on the map bring to the local area? A) Sunny B) Hot C) Clear skies D) Rain Next >

Question 10 What type of weather will the front shown on the map bring to the local area? A) Sunny B) Hot C) Clear skies D) Rain Next >