Energy Transfer Energy Transfer in the in the

AtmosphereAtmosphere

What is the Atmosphere?What is the Atmosphere?

►Surrounds the Earth made up of layers Surrounds the Earth made up of layers of gasesof gases

►Argon , Oxygen , NitrogenArgon , Oxygen , Nitrogen►Exosphere, Thermosphere, Exosphere, Thermosphere,

Mesosphere, Stratosphere, Mesosphere, Stratosphere, Troposphere Troposphere

►Different temperaturesDifferent temperatures

► The atmosphere and hydrosphere are the The atmosphere and hydrosphere are the to essential parts of the climate system,to essential parts of the climate system,

► Firstly as they both are able to absorb Firstly as they both are able to absorb and store thermal energy , so they act as and store thermal energy , so they act as heat sinks.heat sinks.

► Secondly, by absorbing the energy and Secondly, by absorbing the energy and storing it, it creates a big impact on our storing it, it creates a big impact on our atmosphere. Therefore energy transfer by atmosphere. Therefore energy transfer by the atmosphere regulates the the atmosphere regulates the temperature of the earth. temperature of the earth.

How Is Energy Transferred in How Is Energy Transferred in the Atmosphere?the Atmosphere?

►Conduction, convection, radiationConduction, convection, radiation► Conduction is when heat gets transferred in solids Conduction is when heat gets transferred in solids

and fluids by molecules bumping into each other. and fluids by molecules bumping into each other. Convection is when molecules (heat) moves Convection is when molecules (heat) moves throughout a liquid or gas. Radiation is when throughout a liquid or gas. Radiation is when particles or waves are transferred in a medium or particles or waves are transferred in a medium or space, in the form of electromagnetic waves.space, in the form of electromagnetic waves.

►Types of energy transferred : Kinetic, Types of energy transferred : Kinetic, Potential, Thermal etc.Potential, Thermal etc.

Radiation in the AtmosphereRadiation in the Atmosphere

►Source : SunSource : Sun►Radiation energy is absorbed, Radiation energy is absorbed,

reflected, scattered, transmittedreflected, scattered, transmitted►Most of the energy is absorbedMost of the energy is absorbed►Thermal energy = the energy present Thermal energy = the energy present

in the motion of particles at a in the motion of particles at a particular temperature (Science particular temperature (Science Perspectives 10)Perspectives 10)

AbsorptionAbsorption

►Turns energy into another type of Turns energy into another type of energy, eg. Thermal energyenergy, eg. Thermal energy

►Water vapor , carbon dioxide, ozone, Water vapor , carbon dioxide, ozone, major absorbing gasesmajor absorbing gases

►Clouds, atmosphere , land radiates Clouds, atmosphere , land radiates energy back into spaceenergy back into space

TransmissionTransmission

►Some energy passes through Some energy passes through unabsorbedunabsorbed

►This creates atmospheric windowsThis creates atmospheric windows►Only certain types of light can pass Only certain types of light can pass

through, mostly visible light, some radio through, mostly visible light, some radio waves and infrared lightwaves and infrared light

►Only a very tiny amount of UV light Only a very tiny amount of UV light passes through or it would be very passes through or it would be very dangerousdangerous

ReflectionReflection

►Able to see around us because of Able to see around us because of reflectionreflection

►Atmosphere + Clouds reflect 26% of Atmosphere + Clouds reflect 26% of sunlight back into spacesunlight back into space

►Warmer during cloudy nights because Warmer during cloudy nights because energy radiated from the land gets energy radiated from the land gets reflected back down : The Blanket reflected back down : The Blanket EffectEffect

ScatteringScattering

►Small particles in atmosphere cause Small particles in atmosphere cause light rays to scatter into different light rays to scatter into different directionsdirections

►Three types : Rayleigh, Mei , Non-Three types : Rayleigh, Mei , Non-SelectiveSelective

►No transformation of energy, just No transformation of energy, just distribution to different parts of distribution to different parts of atmosphere atmosphere

Rayleigh ScatteringRayleigh Scattering

►Wavelength of radiated light is bigger Wavelength of radiated light is bigger than particle it’s travelling throughthan particle it’s travelling through

►Sky appears blue because of thisSky appears blue because of this

►Blue light = higher energy = smaller Blue light = higher energy = smaller wavelength = more scatteringwavelength = more scattering

Mei ScatteringMei Scattering

►Lower in the atmosphereLower in the atmosphere►Diameter of wave droplets same as Diameter of wave droplets same as

wavelengthwavelength►Almost an equal amount of scattering Almost an equal amount of scattering

of visible light so clouds look of visible light so clouds look white/greywhite/grey

Nonselective ScatteringNonselective Scattering

►Even lower in the atmosphereEven lower in the atmosphere►Particle is greater than the wavelength Particle is greater than the wavelength

of lightof light►Scatters light equally, therefore the Scatters light equally, therefore the

sky looks whitish when there is a haze sky looks whitish when there is a haze

ConductionConduction

►Thermal energyThermal energy►Air is a really poor conductor of heatAir is a really poor conductor of heat►Conduction happens in really low level Conduction happens in really low level

of atmosphere by the Earth’s surface of atmosphere by the Earth’s surface (land)(land)

►Cool air falls, hot air rises, hot air from Cool air falls, hot air rises, hot air from the land rises and circulates through the land rises and circulates through atmosphereatmosphere

ConvectionConvection► Thermal energy Thermal energy ► Sea breeze, land breeze can be explained using Sea breeze, land breeze can be explained using

convectionconvection► Sea breezes occur during day time , when the sun-Sea breezes occur during day time , when the sun-

heated land heats the air by convection. The land heated land heats the air by convection. The land heats the air above it more than the water heats the heats the air above it more than the water heats the air above it because land absorbs more heat. Cold air air above it because land absorbs more heat. Cold air = more dense Warm air = less dense. Warm air rises, = more dense Warm air = less dense. Warm air rises, cold air from water takes it’s place = sea breezecold air from water takes it’s place = sea breeze

► Land breezes occur during the night. Land becomes Land breezes occur during the night. Land becomes cooler quicker than water = land breezecooler quicker than water = land breeze

Convection CurrentsConvection Currents► When the suns rays reaches the equator When the suns rays reaches the equator

with greatest intensity, the air at the with greatest intensity, the air at the equator heats up and becomes less dense.equator heats up and becomes less dense.

► The colder air moves the dense air above it, The colder air moves the dense air above it, forcing the worm air up in the atmosphere, forcing the worm air up in the atmosphere, this creates a area of low pressure below it.this creates a area of low pressure below it.

► When the warm air is high in the When the warm air is high in the atmosphere, it spreads out towards the atmosphere, it spreads out towards the poles and cools down. And the cooler air poles and cools down. And the cooler air sinks back to the earths surface, creating sinks back to the earths surface, creating an area of high pressurean area of high pressure

► These cold and warm air creates a circular These cold and warm air creates a circular current called a convection current.current called a convection current.

Convection Currents con.Convection Currents con.

► A circular current in air and other fluids caused A circular current in air and other fluids caused by the rising of warm fluid as cold fluid sinksby the rising of warm fluid as cold fluid sinks

► Convection currents are one of the main way Convection currents are one of the main way that energy is transferred in the atmosphere.that energy is transferred in the atmosphere.

Prevailing WindsPrevailing Winds

► Air going from high pressure to low pressure = Air going from high pressure to low pressure = windwind

► Prevailing winds = always blow in the same Prevailing winds = always blow in the same wayway

► Prevailing winds move around the Earth due Prevailing winds move around the Earth due to Earth’s rotationto Earth’s rotation

► Carries warm air from equator to polesCarries warm air from equator to poles► Takes warm water from ocean to the polesTakes warm water from ocean to the poles► Prevailing winds moving over ocean carrying Prevailing winds moving over ocean carrying

water to land and condenses = rainwater to land and condenses = rain

► Green house effect is a natural Green house effect is a natural process whereby gases and clouds process whereby gases and clouds absorb infrared radiation emitted absorb infrared radiation emitted from earths surface and radiate it, from earths surface and radiate it, heating the atmosphere and earths heating the atmosphere and earths surface.surface.

►The ocean and atmosphere are connected. The ocean and atmosphere are connected. ►They work together to move heat and fresh They work together to move heat and fresh

water across the globe. water across the globe. ►Wind-driven and ocean-current circulations Wind-driven and ocean-current circulations

move warm water toward the poles and colder move warm water toward the poles and colder water toward the equator. water toward the equator.

►The ocean can store much more heat than the The ocean can store much more heat than the land surfaces on the Earth. The majority of the land surfaces on the Earth. The majority of the thermal energy at the Earth’s surface is thermal energy at the Earth’s surface is stored in the ocean. stored in the ocean.

►Thus, the absorption and movement of energy Thus, the absorption and movement of energy on the Earth is related to the ocean-on the Earth is related to the ocean-atmosphere system.atmosphere system.

► Heat is transferred to the surface of the Heat is transferred to the surface of the Earth from the hot Earth's core by Earth from the hot Earth's core by conduction and from radiation from the conduction and from radiation from the Sun.Sun.

► The atmosphere is heated by absorption The atmosphere is heated by absorption of some of the electromagnetic of some of the electromagnetic radiation from the Sun, and contact with radiation from the Sun, and contact with the warm surface of the land and water. the warm surface of the land and water.

► The warm land and water also radiates The warm land and water also radiates infrared, some of which is absorbed by infrared, some of which is absorbed by the atmosphere, adding to its thermal the atmosphere, adding to its thermal energy. The remaining heat on the energy. The remaining heat on the surface is sent out into space in the surface is sent out into space in the form of infrared radiation.form of infrared radiation.

How does energy transfer in the How does energy transfer in the atmosphere help the Earth?atmosphere help the Earth?

► It blocks out/absorbs a lot of UV light, It blocks out/absorbs a lot of UV light, which is very dangerous in more than which is very dangerous in more than a little quantitya little quantity

► It moderates the Earth’s temperature It moderates the Earth’s temperature and keeps it stableand keeps it stable

►Radiation brings sunlight to Earth and Radiation brings sunlight to Earth and we need it to survivewe need it to survive

Energy Transfer in Energy Transfer in OceansOceans

► In every part of the world, the presence of In every part of the world, the presence of large bodies of water is a contributor to large bodies of water is a contributor to climate differences. climate differences.

► Water has a higher heat capacity than Water has a higher heat capacity than rocks or the atmosphere, meaning that rocks or the atmosphere, meaning that oceans can store much more heat. oceans can store much more heat.

► During the summer days the land gets During the summer days the land gets hotter than the nearby water and the hotter than the nearby water and the warm air starts to rise above causing warm air starts to rise above causing oceans to replace the rising air. During oceans to replace the rising air. During the winter the air over the land cools the winter the air over the land cools faster than air over water. The water from faster than air over water. The water from the ocean radiates some of its stored heat the ocean radiates some of its stored heat into the air and this warm air begins to into the air and this warm air begins to rise. The cooled air over the land moves in rise. The cooled air over the land moves in to take its place. to take its place.

► Oceans are considered as a heat sink Oceans are considered as a heat sink because they can absorb and store because they can absorb and store thermal energy and lastly, serve as thermal energy and lastly, serve as temperature buffers for the ocean and temperature buffers for the ocean and atmosphere system.atmosphere system.

Water BodiesWater Bodies

Water Bodies as Water Bodies as Temperature buffers Temperature buffers

► The northern hemisphere is 39 The northern hemisphere is 39 percent land and 61 percent ocean. percent land and 61 percent ocean. The southern hemisphere is 19 The southern hemisphere is 19 percent land and 81 percent ocean. percent land and 81 percent ocean. Due to larger portion of water in Due to larger portion of water in the southern hemisphere the land the southern hemisphere the land south of the equator experience an south of the equator experience an annual temperature variation by annual temperature variation by 7.3 degrees Celsius from summer 7.3 degrees Celsius from summer to winter. In the northern to winter. In the northern hemisphere the variation could be hemisphere the variation could be up to 14.3 degrees Celsius. up to 14.3 degrees Celsius.

Regional ClimateRegional Climate► The great lakes are The great lakes are

also known for the also known for the strong moderating strong moderating effect they have on the effect they have on the climate of the areas climate of the areas that surrounded these that surrounded these lakes. These huge lakes. These huge water masses keep water masses keep summer and winter summer and winter temperature moderate, temperature moderate, they also provide a lot they also provide a lot of moisture. of moisture.

► Oceans are warmer near the equator than Oceans are warmer near the equator than oceans near the polar region. The oceans near the polar region. The atmospheric circulation that is set up atmospheric circulation that is set up between the equator and the poles helps between the equator and the poles helps in the redistribution of water masses. in the redistribution of water masses.

► Wind that blows over the ocean surface Wind that blows over the ocean surface drags and starts to move the surface drags and starts to move the surface water, these currents are influenced by water, these currents are influenced by the Coriolis force. The Coriolis force is the Coriolis force. The Coriolis force is used to describe the effect of Earth’s used to describe the effect of Earth’s rotation on the motion of moving objects. rotation on the motion of moving objects.

► Ocean currents are influenced by the Ocean currents are influenced by the position of landmasses. In the Pacific position of landmasses. In the Pacific currents correspond to the patterns of the currents correspond to the patterns of the surface winds; currents are more complex surface winds; currents are more complex near the Indian and Atlantic Ocean. In the near the Indian and Atlantic Ocean. In the North Atlantic, the Gulfstream pushes the North Atlantic, the Gulfstream pushes the warm water towards the North Pole and warm water towards the North Pole and cold air back towards the equator. cold air back towards the equator.

Ocean Currents and Coriolis Ocean Currents and Coriolis Force Force

► The region that lies between 23.5 degrees The region that lies between 23.5 degrees north and 23.5 degrees south of equator is north and 23.5 degrees south of equator is called tropics. This region receives a large called tropics. This region receives a large amount of solar energy which creates a flow amount of solar energy which creates a flow of warm current, which flows towards the of warm current, which flows towards the poles. When the current reaches the poles it poles. When the current reaches the poles it starts its journey back towards the equator, starts its journey back towards the equator, this process is defined by great ocean this process is defined by great ocean conveyor belt. In a conveyor the currents conveyor belt. In a conveyor the currents carrying warmer and less dense water move carrying warmer and less dense water move in one direction while currents carrying salty in one direction while currents carrying salty and cold water move in the opposite and cold water move in the opposite direction. direction.

► The conveyor occurs due to two facts. First The conveyor occurs due to two facts. First reason is due to the variation in water reason is due to the variation in water temperature, as warm water is lighter and temperature, as warm water is lighter and less dense than the cold water. Second less dense than the cold water. Second reason is due to the difference in amount of reason is due to the difference in amount of salt present in the ocean water. As salt present in the ocean water. As freshwater is lighter and less dense than the freshwater is lighter and less dense than the salty water. Due to these two factors stated salty water. Due to these two factors stated the creation of thermohaline circulation is the creation of thermohaline circulation is created. created.

Conveyor Belt and Conveyor Belt and Thermohaline Circulation Thermohaline Circulation

Cycle of Ocean Current Cycle of Ocean Current ► Within the oceans there is a sophisticated Within the oceans there is a sophisticated

system of massive streams that helps to system of massive streams that helps to circulate the ocean waters. The gulf stream circulate the ocean waters. The gulf stream that moves into the North Atlantic sinks as it that moves into the North Atlantic sinks as it cools and returns south though the Atlantic cools and returns south though the Atlantic seafloor, it then flows as a bottom current up seafloor, it then flows as a bottom current up until the South Atlantic form there it rises to until the South Atlantic form there it rises to the surface in the Indian Ocean and the Eastern the surface in the Indian Ocean and the Eastern Pacific to warm up and then turns west towards Pacific to warm up and then turns west towards the Gulfstream. For a complete run through the Gulfstream. For a complete run through this current system takes about 1000 years. this current system takes about 1000 years.

► This current system is very delicate minor This current system is very delicate minor changes can upset the balance of temperature changes can upset the balance of temperature differences and prevailing winds. Scientists differences and prevailing winds. Scientists have said that the melting of the Greenland have said that the melting of the Greenland icecap can cause so much melt water of low icecap can cause so much melt water of low salinity and density that this could prevent the salinity and density that this could prevent the Gulfstream from sinking and returning as a Gulfstream from sinking and returning as a southward bottom current. This would affect southward bottom current. This would affect the current system and cause waters near the the current system and cause waters near the equator and regions close to the equator to get equator and regions close to the equator to get warmer and northern Europe to get colder warmer and northern Europe to get colder

Cycle of Ocean Cycle of Ocean CurrentCurrent

Latent Heat Latent Heat ►The energy required to The energy required to change the phase of a change the phase of a substance is known as a latent substance is known as a latent heat. heat. ►The quantity of heat The quantity of heat absorbed or released by a absorbed or released by a substance undergoing a substance undergoing a change of state.change of state.►Latent Heat can also be Latent Heat can also be called Heat of transformation. called Heat of transformation. ►The latent heat absorbed by The latent heat absorbed by air when water vapour air when water vapour condenses is primarily the condenses is primarily the source of the power of source of the power of thunderstorms and hurricanes.thunderstorms and hurricanes.►EXAMPLE : The polar ice caps EXAMPLE : The polar ice caps are examples of latent heat .are examples of latent heat .

►The Earth receives 174 The Earth receives 174 petawatts of solar radiation at petawatts of solar radiation at the upper atmosphere.the upper atmosphere.►30% of that light is reflected 30% of that light is reflected back to space. And the other back to space. And the other 70% is absorbed by oceans, 70% is absorbed by oceans, clouds, and other land masses.clouds, and other land masses.►Solar energy warms up the air Solar energy warms up the air and the latent energy makes and the latent energy makes the clouds rain . the clouds rain . ►Solar energy keeps the surface Solar energy keeps the surface level of the Earth at 14 degrees level of the Earth at 14 degrees Celsius Celsius ►Water in general is evaporated Water in general is evaporated due to solar energy, which due to solar energy, which eventually leads to eventually leads to condensation and precipitation. condensation and precipitation.

Solar energy and Solar energy and the Oceans.the Oceans.

►Due to Energy transfer we Due to Energy transfer we get form solar energy and get form solar energy and other forms we get different other forms we get different weathers. weathers. ►The Effects of the energy The Effects of the energy transfers in the future could transfers in the future could result in melting Ice caps, result in melting Ice caps, higher sea levels , flooding, higher sea levels , flooding, and warmer climate . and warmer climate . ► The Polar Ice Caps absorb a The Polar Ice Caps absorb a lot of the CO2 and solar lot of the CO2 and solar radiation. radiation. ►If these melt then there will If these melt then there will be nothing to reflect the be nothing to reflect the harmful radiation and to harmful radiation and to absorb CO2 .absorb CO2 .

Effects of energy Effects of energy transfer transfer

By : Mariam, Sohum, Sarah, By : Mariam, Sohum, Sarah, Teyyab.Teyyab.