Understanding the Atmosphere Layers and Temperature Concepts

1. Warm uppg. 70 • What are the 5 layers of the atmospherestarting with the closest to Earth’s surface? • What are some characteristics of the thermosphere? • In which layer is the ozone present? • How does ozone aid in the radiativeprocesses of the Sun?

2. State of the atmosphere Pg. 69

3. Temperature vs. heat • Temperature deals with the movement of particles • Heat is the transfer of energy from a higher energy substance to a lower energy substance • Heat fuels atmospheric processes and we use temperature to measure and interpret that energy

4. Measuring Temperature • Kelvin is the SI unit of temperature • Based on absolute zero • To convert from Celsius to Kelvin, add 273 • Fahrenheit = 9/5 0C + 32 • Celsius = (0F -32) x 5/9

5. Temperature practice problems • Convert 19 degrees Celsius to Kelvin • Convert 109 degrees Fahrenheit to Celsius • Convert 23 degrees Fahrenheit to Kelvin

6. Dew Point • Another atmospheric measurement • The air must be cooled to a certain temperature to reach saturation • Saturation- the point where the air holds as much water as possible • Condensation will not occur unless the dew point is reached • Dew point often called the condensation temperature

7. Vertical temperature changes • Temperatures are cooler at higher elevations in the troposphere because the air is further from the heat source • Earth radiates energy from the sun to warm the atmosphere • Air masses will drop 100C for every 1000 m • Called dry adiabatic lapse rate (no heat is being added or taken from surrounding air)

8. Lifted condensation level • Air will continue to rise and cool until it reaches its condensation temperature • The height at which this happens is called the LCL • Corresponds to the base of the cloud • Above LCL, saturated air cools slower (40C / 1000m) • Called moist adiabatic lapse rate

10. Air pressure and density • We have 14 lbs/ sq. in of pressure on us constantly • As you go up in elevation, pressure decreases • As you go down in elevation, density increases  particles are squished closer because of pressure • Direct relationship between pressure and density

11. Pressure-Temperature- Density • Relationship between temperature and pressure is directly proportional • Relationship between temperature and density is inversely proportional • Temp increase  density decrease • This is why hot air rises

12. Reltionships • Draw a table in your notes for the relationships between temperature and pressure and temperature and density • Ex. T , D

13. Temperature inversions • Sometimes, temperature can increase as you move upward in the troposphere • Called a temperature inversion • Happens on cold nights where the air is not receiving heat from the Earth • Can trap pollution

14. Wind • Wind is caused by air moving from areas of high pressure to areas of lower pressure • Cool air sinks and pushes warm air up • Measured in mph or km/h • Ships measure in knots • 1 knot = 1.85 km/h • Wind is more forceful in higher altitudes because of less friction

15. Relative humidity • Air always has some amount of water vapor • Measured using humidity • Relative humidity compares the water vapor in an air sample to the amount of water vapor that volume of air is capable of holding • Warm air can hold more moisture than cool • Described using percentages