1. Water in the Atmosphere
Evaporation, transpiration, (evapotranspiration), dew, frost, fog (advection, radiation, upslope), saturated air, humidity, condensation, dew point, cloud formation, types of clouds (cumulous, stratus, cirrus), types of precipitation, orographic, convection, and frontal (cyclonic), thunder and lightening

2. Moisture moves into the atmosphere from evaporation and transpiration
Moisture moves into the atmosphere from evaporation and transpiration
When that water vapour converts back to liquid water, it is called condensation

3. Relative humidity and the dew point
Humidity - the amount of water in the air compared to how much the air can hold
as a percent of the total amount of water based on how much it can hold
When the air contains as much water as it can hold (at a certain temperature), it is SATURATED.
Dew point – the temperature to which the air must be cooled to reach the saturation point
The temperature at which water vapour will condense
Hotter air can hold more moisture than colder air

4. Dew When the surface temperature cools, it cools the air next to it
Water condenses out of the air and forms on surfaces
When the temperature of the surface is below freezing, the deposition is frost

5. Fog Condensation of water vapor near the earth’s surface
Requires that the air mass be humid, rather than dry
If the air reaches saturation (air that cannot hold any more water at that temperature), fog will be produced as soon as it gets colder

6. Radiation or Ground Fog
Occurs at night, as the earth cools through radiation
This cools the moist air layer near the surface to the saturation or dew point
The moisture in these nearby layers condenses into water vapour
Usually on clear nights, when heat can escape the lower atmosphere (cloud cover traps heat)
Also, calm nights when no wind mixes the layers of air

7. http://www. williamsclass

8. Upslope Fog

9. Valley Fog
A type of radiation fog

10. Advection Fog
Occurs when a warm front moves in horizontally over a cold surface, such as a snow pack, or
Warm, moist air comes off the ocean onto the colder land

11. Evapouration Fog A type of advection fog
Cold air flows out onto warm water, or
The warm, moist air contains water that has evapourated into it
As it rises, it cools and fog forms as the vapor condensates
Swimming pools, hot tubs, bodies of water in the fall

12. Orographic Precipitation
Remember that orogeny is the study of mountains?
Orographic precipitation is caused by mountains
Wind pushes warm moist air up the slope of the mountain
Air cools, water vapor condenses, rain falls

13. Convectional Precipitation
Hot summer days
Sun heats the surface
Moisture enters the air through evapouration
Warm air rises, cools, clouds form, precipitation falls

14. Frontal Precipitation
There are different types of fronts – we’ll look at this later
Remember that a front is the line between a warm and cold air mass
As the warm air in this example rises and cools over the cold air mass, clouds form, rain falls