Chapter 11 Atmosphere Atmospheric composition; 78% Nitrogen 21% Oxygen 1% Trace gases

Trace Gases Water Vapor: Invisible gaseous form of water. The amount in the atmosphere can vary greatly based on time of year and location (0%-4%). Carbon dioxide: Green house gas that makes up about 0.04 % in the atmosphere. 150 years ago it was about 0.028 %. This may seem like an insignificant amount until you consider the ozone and its importance. There is about 33 times more CO2 than ozone.

Ozone: Three oxygen atoms combine to form O3 (0 Ozone: Three oxygen atoms combine to form O3 (0.0012% of the atm ) which protects people from the harmful effects of UV radiation. Holes in the ozone layer are created by CFC’s because the O3 is relatively unstable and breaks up to form more stable bonds with the elements in the CFC’s.

Look at page 14 in your ESRT’s. Here you see the same chart Look at page 14 in your ESRT’s. Here you see the same chart. Which layer has the most moisture in it? Troposphere --> AKA the “weather sphere”

The troposphere layer also has the most mass. What does temperature do as you increase in altitude with in the troposphere? Does this change occur in each layer? Stratosphere: The layer of atm above the troposphere which is composed of ozone.

Three methods of energy transfer 1. Radiation: The transfer of energy through space. -50% absorbed and or reflected by the clouds and atmosphere back into space before it hits the Earth’s surface.

Three methods of energy transfer continued… 2. Conduction: The transfer of energy when molecules are in contact with each other -land heats up a thin layer of the air above it. 3. Convection: Heated fluids are less dense and rise through the medium creating a convection cell.

Section 11.2 State of the Atmosphere Temperature: A measurement of how rapidly or slowly molecules move around. Heat: Is the transfer of energy that occurs because of a difference in temperature.

Section 11.2 State of the Atmosphere Three temperature scales, all in your ESRTS Fahrenheit: Old English system Celsius: Based on the freezing and boiling points of water. Kelvin: Based on Absolute zero being zero on this scale.

Section 11.2 State of the Atmosphere Dew Point: The temperature at which air needs to cool in order for condensation to occur. Condensation: The phase change of water vapor to a liquid. This requires the air to cool, and a surface to condense on.

Section 11.2 State of the Atmosphere *In the first layer of the atmosphere (troposphere) air temperature decreases as you increase in altitude. *Dry adiabatic lapse rate: The rate at which air cools in unsaturated (dry) air.

*Air that continues to rise will reach the Lifted Condensation Level or LCL: the height at which condensation occurs (clouds form). From here the air cools at a slower rate in the now saturated air. This is known as the Moist adiabatic Lapse rate.

Air Pressure and Density relationships As Temp Pressure As Temp Pressure As Temp Density

Temperature inversion: An increase in temperature with height in an atmospheric layer.

Wind: air movement that results from a difference in air pressure Wind: air movement that results from a difference in air pressure. Air flows from High to low pressure.

Humidity: The amount of water vapor in the air.

Relative humidity: The amount of water vapor in air compared to how much the air could hold.

Section: 11.3 Condensation nuclei: Small particles in the atmosphere that water can condense on to form water droplets. *Smoke *Salt *Dust

Orographic lifting: When an air mass is forced up a mountain, it cools, reaches the dew point temperature and forms clouds and often rains.

Here is an example of Orographic lifting

Here is another example of Orographic lifting

Another way in which clouds form is when air masses collide Another way in which clouds form is when air masses collide. When a less dense warm air mass hits a cold air mass, the warm air is forced up.

Convergence When air converges from different directions some of it is forced to rise. This occurs in areas of Low pressure.

Stability: The ability of an air mass to resist rising.

Latent Heat: The energy that is stored in the air until condensation occurs. This heat is the result of the energy it takes to change a liquid to a gas. In your esrts it is given in Joules, not calories!

Types of Clouds Clouds are classified by their shape and by the altitude at which they form.

Types of Clouds Clouds are classified by their shape and by the altitude at which they form.

Types of Clouds Clouds are classified by their shape and by the altitude at which they form.

Types of Clouds Clouds are classified by their shape and by the altitude at which they form.

Types of Clouds Clouds are classified by their shape and by the altitude at which they form.

Evaporation: The phase change from a liquid to a gas Evaporation: The phase change from a liquid to a gas. The amount of Joules needed is 2,260.

Coalescence One way that cloud droplets can increase in size. When cloud droplets collide they get larger. As these larger droplets fall they collide with other droplets. When the droplets are too large to stay suspended in the cloud they fall and it rains.

1. Which layer of the atmosphere contains the most water vapor? Troposphere B) Stratosphere C) Mesosphere D) Thermosphere 2. Which of the following is not a method of energy transfer? A) Conduction B) Convection C) Radiation D) Thermosis

3. Which is not required to form a cloud? Water vapor B) Warming air C) Condensation nuclei D) Cooling air 4. Which is not part of the water cycle? A) Condensation B) Transpiration C) Lithification D) Infiltration 5. Describe the air flow in low pressure (3 things!) and how it makes a cloud. Bonus:How many Joules would it take to vaporize 10 grams of water?