geo exam 2

Hydrosphere is in a...

steady-state equilibrium

Distribution of Earth's water is...

uneven

Covalent bonding

bonding of atoms through the sharing of electrons (very strong)

Polarity

electric charge causing the attraction and repulsion of atoms/molecules

Hydrogen bonding

bonding between water molecules (weaker than covalent, but still strong)

Phase change requires the...

absorption or release of heat energy

Latent heat

energy stored in phase change; it is either released or absorbed

Humidity

amount of water vapor in air

Relative humidity (RH)

Ratio: actual water vapor in air / max water vapor possible at a specific temperature and expressed in a percentage.

Dry air has _____ while wet air has _____

low RH; high RH

Condensation

the addition of more water vapor or a decrease in air temperature

Dew-Point Temperature

The temperature at which the air will become saturated

What are the expressions of humidity?

Relative humidity, Vapor Pressure, and Specific Humidity

Vapor Pressure

air pressure made up of water-vapor molecules

Saturation Vapor Pressure

Air that contains as much water vapor as possible at a given temperature. Water molecules evaporate and exert pressure.

Specific Humidity

mass of water vapor per mass of air at any specified temperature Remains constant as temperature & pressure change. Useful in describing moisture content of large air masses that are interacting in a weather system

Sling psychrometer

measures RH

Air parcel

body of air (>300 m in diameter) with a specific temperature and humidity

What happens if the air parcel is LESS dense than surrounding air?

Parcel rises and expands

What happens if the parcel of air is MORE dense than surrounding air?

Parcel sinks and compresses

Temperature of the volume of air determines...

density of the air parcel

Stability

tendency of an air parcel to remain in place or change vertical position; depends on temperature

Adiabatic

Expansion = Cooling; Compression = Warming

What are clouds?

Aggregate of tiny moisture droplets & ice crystals. Suspended in air. Large enough in volume & concentration to be seen

How are clouds formed?

because air is saturated with water; May contain raindrops, but not initially

Cloud-condensation nuclei

Microscopic particlesDust, soot, ash, aerosols - continentSea salt - ocean Always present

How do we classify clouds?

Altitude (low, middle, high, vertically developed)Shape (flat, puffy, wispy)

Stratus

clouds that form in flat layers

Cummulus

cloud is puffy and formed in heaps

Cirrus

wispy, feathery thin clouds

Nimbus

a rain cloud

Fog

cloud layer on the ground; Air temperature and dew-point temperature are nearly identical at ground level

What are the different types of fogs?

Radiation fog - moist / wet ground cools at night

Advection Fog - Air in one place migrates to where it can condense. Warm to Cold

Evaporation Fog (sea smoke) - water evaporates from water surface - cold air overlying water surface -condensation

Weather

Short-term, day-to-day atmospheric conditions

Climate

Long term weather trends in a region

Meteorology

The study of the atmosphere (physical characteristics and motions)

Air Mass

Distinctive body of air, with characteristics of its source region. Has specific conditions of temperature, humidity, and stability (homogenous) and produce weather patterns

How do you classify moisture in an air mass?

m - maritime [wet], c - continental [dry]

How do you classify temperature in an air mass?

A - Arctic, P - polar, T - tropical, E - Equatorial, AA - Antarctic

Air Mass Modification

As air masses move from their source region, their temperature and moisture characteristics change with the regions they come in contact with

What are the mechanisms for Lift?

Convergent, Convectional, Orographic, Frontal

Convergent Lifting

Air flows (from different directions) toward an area of low pressure

Convectional Lifting

Air is stimulated by local surface heating

Orographic Lifting

Air forced over a topographic barrier

What is an example of Orographic Lifting?

Sierra Nevada (Rainshadow)

Frontal Lifting

Lifting caused by the collision of two air masses

Cold Front

dense air forces lighter warm air aloft (up)

Warm Front

warm air moves up and over dense cold air

Ice Storm

Minimum of 6.4 mm (0.25 in) of ice accumulates on exposed surfaces

Thunderstorms

Fueled by rapid upward movement of warm, moist air (updrafts) eventually cools and condenses. Energy is released due to latent heat from condensation, which heats the air and causes violent updrafts and downdrafts

What are the characteristics of a thunderstorm?

Turbulence, Wind Sheer, and Lightning

How are tornadoes formed?

High winds and updrafts collide creating a circulating low pressure. The cloud begins to lower below the cloud base.The low pressure extends to the ground picking up dust and debris forming a tornado.

What is a mesocyclone?

a spinning, cyclonic, rising column of air, which is typical for a large storm

Most Thunderstorms do not...

produce tornadoes.

Funnel Cloud

rotating column of air; is formed extending from thunderstorm base

waterspout

the tornado is in contact with a body of water

We can predict _____ days in advance, but for _____, we only have minutes.

storms; tornadoes

Tropic Cyclones are another name for...

Hurricanes, typhoons, or cyclones

What are tropic cyclones?

All form destructive storms with high speedsOccur within the tropics

Water is a...

renewable resource (distribution unequal)

hydrological cycle (water cycle)

The circulation and transformation of water through the Earth's atmosphere, hydrosphere, lithosphere and biosphere

The Water-Balance Equation

Effective method to assess portions of the water cycle as they apply to water resources

How do we measure precipitation?

Rain Gauges (measures depth, weight, or volume)

Evapotranspiration

The evaporation of water from soil plus the transpiration of water from plants. Measured with a Lysimeter.

potential evapotranspiration

the amount of evaporation that would occur if a sufficient water source were available. Estimated.

How are deficits formed?

The water demands exceeds the moisture from precipitation, irrigation, and soil moisture.

(Potential Evapotranspiration - Evapotranspiration)

What do deficits result?

Droughts

Surplus

Additional water beyond Potential Evapotranspiration demands

Storage is defined by...

the balance between: recharge (surplus) and soil moisture loss (deficit)

Saturation

occurs when pore spaces are filled with water, unable for plant roots to do gas exchange.

field capacity

ability of a soil to hold water against the downward pull of gravity

wilting point

the water potential at which most plants can no longer retrieve water from the soil.

Where are surface water resources found?

Snow and Ice, Rivers and Lakes, and Wetlands

Snow and Ice

Largest amount of surface freshwater; Snow melts provide streamflow.

Rivers

Vast arterial network of surface runoff (Snow Melts and Ground waters)

Lakes

bodies of water fed by precipitation, streamflow, and groundwater

Wetlands

An area that is permanently or seasonally saturated with water and characterized by vegetation adapted to saturated soils (hydric soils) May develop anaerobic conditions.

Wetlands could contain...

either fresh water or salt water

drainage basin

land area that drains into a specific trunk stream

drainage divide

separates adjacent drainage basins. A raindrop flows to one basin or the other, depending on which side of the divide it falls.

Colorado River Compact

an agreement signed in 1926 that allocated to Wyoming, Colorado, Utah, Nevada, New Mexico, Arizona, California, and Mexico different portions of the Colorado River's normal and stored river flow.

Groundwater Resources

Water below the surface, beyond the soil-moisture zone and the reach of most plant roots

Porosity

spaces or voids between particles in a material such as soil or rock

Permeability

the ability of water to flow through soil or rock

Aquifer

A subsurface body of permeable rock or sediments through which water can flow in amounts adequate for wells and springs

unsaturated zone (zone of aeration)

Pore spaces only partially full of water, lies between the water table and the surface, only partially full of air.

zone of saturation

The lower zone where water accumilates between small rock particles (sand, gravel, and rock)

unconfined aquifer

has a permeable layer on top and an impermeable one beneath

water table

The upper level of the saturated zone of groundwater

confined aquifer

is bounded above and below by impermeable layers

artesian wells

groundwater comes to surface without having to pump

Drawdown

A lowering of the water table

groundwater mining

when rate of water pumping is higher than rate of recharge beyond its capacity.

Land subsidence

sudden sinking or gradual downward settling of the Earth's surface

Earth Fissures

a crack, break or fracture in the rocks associated with land subsidence

Saltwater encroachment

the intrusion of saltwater into the ground with the removal of fresh groundwater

What are the components that reveal general climate types?

temperature, precipitation (Generally its these two),

Insolation, energy availability, air pressure, and air mass

Genetic classification

based on causative factors (e.g., interaction of air masses); based on why a certain mix of climatic ingredients in certain locations occurs

Empirical classification

based on statistical weather data (e.g., precipitation, temperature, potential evapotranspiration)

Empirical Approach

A study conducted via careful observations and scientifically based research.