Weather and Climate Exam 1 Review

Atmosphere definition

a thin layer of gases surrounding Earth, held by gravity

conduction

heat transfer through molecular activity

convection

heat be rising

radiation

electromagnetic energy from da sun

Weather definition

the condition of the atmosphere at any particular place and time

Climate definition

long-term aggregate of weather conditions; sum of all statistical weather info that helps describe a place or region includes extremes

What are the atmospheric variables?

air temp, humidity, cloud cover, precipitation, atmospheric pressure, and wind

Permanent gases

• take up 99.999% of atmospheric mass

• consists of: nitrogen, oxygen, argon, helium, krypton, xenon, and hydrogen

Variable gases

water vapor, carbon dioxide, ozone, and methane

Water Vapor

• makes up .25% of total atmosphere mass

• concentration decreases with altitude

• mostly found in the lowest 5km of the atmosphere

• near-surface ranges from <1% (deserts) to about 4% (tropics)

selective absorbers

H2O and CO2

absorb and re-emit infrared energy

Seasons are a result of:

• changing sun angle

• changing length of daylight

Axis is always pointed in the same direction (T/F)

True

Summer solstice

June 21-22

vertical rays are at the Tropic of Cancer (23 and ½ n lat)

Winter solstice

December 21-22

vertical rays at the Tropic of Capricorn

Autumnal equinox

September 22-23

sun’s rays are at the equator

Spring equinox (vernal)

March 21-22

sun’s rays are at the equator

Insolation

incoming solar radiation

Solar Altitude

angualr distance between the horizon and the sun

Solar declination

latitude recieving direct (90 degrees) rays of solar energy

Earth is nearer to the sun in January v July (T/F)

True

Why are summer temps in the Southern Hemisphere cooler than summer temps in the Northern Hemisphere?

The additional energy is absorbed by all the water in the Southern Hemisphere and circulated, this also keeps the Southern Hemisphere warmer in the winters due to the water’s large heat capacity

The days from the spring equinox to the autumn equinox is 7 days longer than autumn to spring eq (T/F)

True

What is the most important temperature control?

Insolation

What is the most important factor in solar receipt?

Latitude

Which latitudes receive the most solar energy?

low latitudes near the equator

What is differential heating of land and water?

Land heats and cools faster than water

What is specific heat?

The amount of energy required to raise the temperature of 1g of a substance 1 Celsius degree

The two most important temperature controls:

Insolation and Differential Heating

Normal environmental lapse rate

avg rate temp decrease 3.6 degrees F per 1000 ft increase

Calorie

the measure of energy it takes to raise 1g of water by 1 degrees Celsius

Latent heat

stored heat required to change water from one phase to another

Evaporation is a cooling process (T/F)

True

sublimation

solid to gas

heat absorbed

deposition

gas to solid

heat released

saturation

the peak for water vapor in the air

absolute humidity is the measure of

the mass of water vapor per volume of air

Carbon dioxide

• a variable gas

• makes up .036% of atmospheric mass

• concentration about 360 ppm

Troposphere

lowest level of atmosphere

where all the weather is

temp decreases with altitude

Stratosphere

above the Troposphere

temp increases with altitude

stable, low moisture, ozone concentration at 25km

Mesosphere

above stratosphere

temp decreases with altitude

Thermosphere

above mesosphere

temp increases with altitude

no definite endpoint

Homosphere (atmospheric composition)

• lower region of the atmosphere

• gases are well mixed due to turbulent mixing

• gases consist of: 78% N2 and 21% O2

Heterosphere (atmospheric composition)

• upper region of the atmosphere

• gases are layered by weight

• almost no mixing

Ionosphere (structure by function)

• upper mesosphere thru thermosphere

• electrified region with a lot of ions and free electrons

• filters harmful wavelengths

• consists of D, E, and F layers. D exists in daylight absorbing AM radio waves