1. WEATHER DYNAMICS

2. 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

3. 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)

4. 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

6. 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!

7. 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

8. 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

9. 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

10. 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:

11. 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

12. 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

13. 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

14. 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

15. SEA BREEZE & LAND BREEZE: CONVECTION CURRENTS AT WORK

16. 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

17. 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