chapter 6 book notes - Physical Geography Book Notes...

Physical Geography Book Notes
Chapter 6
Atmospheric Moisture
I. The Impact of Atmospheric Moisture on the Landscape
a. Water vapor can condense to form haze, fog, cloud, rain, sleet, hail, or snow
b. Rain and snow melting can cause erosion of land
c. Absence of precipitation can cause damage to plants
II. The Nature of Water: Commonplace but Unique
a. Polar- one side slightly negative, the other slightly positive
i. causes the molecules to form hydrogen bonds
b. Properties of Water
i. Water is a liquid in most places on earth
ii. Water expands, instead of contracting, when it freezes
1. ice floats because it is less dense
iii. High surface tension
iv. Water sticks to other substances easily
1. capillary action in plants
v. universal solvent because it can dissolve almost any substance
vi. attracted to other polar molecules
vii. water can absorb a lot of energy while only slightly increasing the temp
III. Phase Changes of Water
a. Latent heat- the energy required for a phase change
b. In the atmosphere latent heat is released through condensation
IV. Water Vapor and the Hydrologic Cycle
a. Amount of water vapor in the atmosphere is varying
b. Hydrologic cycle, water cycle, is how water changes phases and moves in the atmosphere
V. Evaporation
a. Vapor pressure is the pressure exerted by water vapor
b. When the vapor is giving off maximum pressure, the air is saturated
i. Rate of evaporation is higher if temp and windiness are higher and the air is dry
c. Evapotranspiration is water that evaporates from land sources
i. Potential evapotranspiration is based on how wet or dry the ground is
ii. Potential evapotranspiration rate exceeds the precipitation rate- no water is stored
VI. Measures of Humidity
a. Absolute humidity is the mass of water vapor in a given volume of air (g/m^3)
b. Specific humidity is the mass of water vapor in a given mass of air
c.