WEATHER DYNAMICS https://www.youtube.com/watch?v=cBdxDFpDp_k

Weather Dynamics this unit we will look at what makes weather happen all weather events on Earth are caused almost exclusively by the Sun energy from the fusion reactions of the Sun is released in a form called electromagnetic radiation and it travels to Earth only certain ‘kinds’ of radiation from the Sun influence the weather on Earth

the 3 distinct ‘kinds’ of energy that affect weather on Earth are: only energy with certain wavelengths is responsible for influencing weather the 3 distinct ‘kinds’ of energy that affect weather on Earth are: Infrared - all objects radiate or give off this kind of energy. carries the least amount of energy. Visible Light - ROYGBIV Ultraviolet - carries the largest amount of energy (ie: has the shortest wavelength)

THERMAL ENERGY when the infrared, visible light and ultraviolet energy from the Sun reaches Earth it is transformed and re-emitted as thermal energy as the EM radiation approaches the Earth it begins to run into particles and transfers energy to the particles as the particles absorb more and more energy they heat up energy due to the movement of particles heat is simply the transfer/flow of thermal energy from one object to another there are 3 ways of transferring thermal/heat energy: Conduction Convection Radiation

What is takes...it gives back! out of all the EM radiation from the Sun that is converted into thermal energy on Earth: 70% is absorbed 30% is reflected back into space the Earth does not just keep heat up and up and up because all objects that absorb thermal energy from the Sun release most of this energy back to space (as infrared) What is takes...it gives back!

ENERGY AND WATER interactions between incoming energy and water have a major influence on the weather we experience 70% of the Earth is ocean 30% of the Earth is land with clouds (water) floating above it FACT: It takes more energy to heat up water than it does to heat up dry land

ENERGY AND WATER Specific Heat Capacity: Examples: defined as ‘the amount of energy required to raise the temperature of one gram of a substance one degree Celsius’ Examples: Specific heat capacity of water: 4.18J/gC Specific heat capacity of dry land: 1.00J/gC

ENERGY AND WATER Heat of Fusion: Heat of Vaporization: Amount of energy required to change a solid ↔ liquid given in J/g Heat of Vaporization: Amount of energy required to change a liquid ↔ gas also given in J/g

HEATING OF LAND VS HEATING OF AIR Heating Land land & water absorb a lot of short-wavelength (ultraviolet) radiation from the sun dry land heats up much more quickly than does water for 3 reasons:

HEATING OF LAND VS HEATING OF AIR 1. Because of heat capacity: Example: Water: 4.18 J/gC Dry land: 1.00 J/gC It takes 4 times as much energy to raise the temperature of water 1 degree than it does land

HEATING OF LAND VS HEATING OF AIR 2. Solar radiation does not penetrate land as deeply as it does water energy is not as ‘concentrated’ when it encounters water 3. Water is constantly moving mixing cooler water with the water that has been warmed up

Heating Air air absorbs long-wavelength radiation (infrared) emitted from the Earth air close to the ground heats up more quickly than does air that is further from the ground when air is heated it expands (becomes less dense) so it rises This can create local wind

Heating Air Also, as the air rises it gets farther away from its energy source (the Earth) and cools off as the air cools it becomes more dense and sinks this circular cycle of air rising and falling is called a convection current

SEA BREEZE & LAND BREEZE: CONVECTION CURRENTS AT WORK

air over water rises (because it is warmer) AT NIGHT: air over land cools down more quickly then air over water air over water rises (because it is warmer) cool air over land moves in to replace air over water a convection current forms winds blows from land → Land Breeze

cool air over water moves in to replace air over land DURING DAY: air over land heats up more quickly then air over water air over land rises cool air over water moves in to replace air over land a convection current forms Wind blows in from water → Sea Breeze