Section D - Earth's Atmosphere

What are series of concentric layer?

gaseous envelope surrounding earth

What is an example of fluid properties that are constantly changing spatially and temporally?

weather

What does being held to the earth by gravity create?

atmospheric pressure

Most of the atmosphere’s mass is near the _

surface

_ is what you expect, _ is what you get

• climate

• weather

What is climograph?

graph of the climate

What consistent gases compose of the atmosphere? (3) + percentage

• 78% nitrogen

• 21% oxygen

• 1% argon

What makes up less than 1% of gases in atmosphere?

• variable (trace) gases:

  • carbon dioxide

  • water vapor

  • ozone

Why is the atmospheric water vapor critical/ important? (4)

• determines the humidity

• source of clouds/ precipitation

• absorbs and stores heat energy

• moves with airflow transporting energy and moderating temperature

Variation of atmospheric water vapor depend on: (2)

• air temperature

  • warmer air can hold more water vapor than cooler air

• proximity to large bodies of water

What is photosynthesis?

plants absorb carbon dioxide and release oxygen and water as a by-product

What is greenhouse effect? (2)

• trapping of longwave radiation

• warms the atmosphere, which warms the earth

Carbon dioxide enters atmosphere through a source and leaves through what?

a sink

Source: volcanic eruption what is the sink?

chemical reactions with rocks

Source: decay of living matter, sink?

oceans

Source: respiration, sink?

plants (photosynthesis)

Sources: burning fossil fuels (coal, oil, natural gas), sink?

soil

Concentrations of CO₂ increase how much in the past 200 years?

>30%

What are particulates/ aerosols?

minute suspended particles in the atmosphere, existing in both liquid and solid form

Examples of particulates/ aerosols in solid form: (8)

• snow

• hail

• pollutants

• soil (dust)

• smoke

• ash

• pollen grains

• salt spray

Examples of particulate/ aerosols in liquid form (2)

• clouds

• rain

How do particulates help precipitation form?

by acting as condensation nuclei (tiny surfaces for water vapor to condense around

What is hygroscopic?

absorb water

Particulates absorb or reflect energy, impacting _

temperature

Particulates/ Aerosols influence:

air quality

What year did scientists first report dust storms in S. Alsaka?

1911

Dust storms play a role in what two things?

• supplying nutrients (iron)

• fuel for phytoplankton blooms

Loess

fine grained sediment created by glacial ice pulverizing rock

Earth’s atmosphere can be divided up into layers or regions based on: (3)

• thermal properties

• composition

• functional properties

What are the four thermal properties?

• troposhere

• stratosphere

• mesosphere

• themosphere

Example of composition (2)

• homosphere

• heterosphere

Example of functional properties

ozone layer

Four thermal layers: (3)

• distinguished by temperature changes and gases

• differs in density and composition

• “sphere” vs “pause”

Which thermal layer is the lowest?

the troposphere

The troposphere is the most active zone with: (3)

• majority of nonmarine living organisms

• weather occurs in this layer

• verticle mixing is common

In which two thermal layers is the temperature decreasing with increasing altitude?

• troposphere

• mesosphere

Troposphere- temperature decreases at an average rate of _ degrees per 1000m (Environmental Lapse Rate)

6.5

What is the temperature and height of tropopause?

• -57 degrees C

• 8-18 km, average ~12km

Almost all cloud tops end at which layer?

tropopause

The tropopause is shallower over poles and higher over equator over what?

thermal expansion and earth’s rotation

Reversal of normal temperature pattern so that air temperature increases with _ (in the troposphere)

altitude

Dust dome keeps air from doing what?

rising

Which thermal layer is immediately above the tropopause?

the stratosphere

In the stratosphere layer, temperature increases with increasing altitude due to what?

ozone absorbing UV rays

Stratopause is the _ limit of the the stratosphere

upper

In which thermal layer do commercial jets fly?

in the stratosphere layer

With troposphere, there is much verticle mixing which is

pollutants

With stratosphere, there is little verticle mixing which is

slow exchange of gases with troposphere (stagnant)

In which thermal layer do all weather and climate occur?

troposphere

Which thermal layer is above the stratopause?

the mesosphere thermal layer

Which thermal layer is the coldest?

mesosphere

In stratosphere: little water vapor and few _

impurities

Solar radiation (in the mesosphere layer) reduces gas molecules to ions which (2)

• strips an electron to form a positively charged ion

• disrupts some satellite communication

Meteors burn up in the mesosphere layer, most the size of:

a grain of sand

The thermosphere is the uppermost layer where: (2)

• temperature increases with altitude

• intense solar reactions cause molecules to vibrate at very high speeds, creating kinetic energy

What is the height of thermosphere layer?

80-480 km

In the thermosphere layer, gases are sorted into what based on molecular mass?

sublayers

What is orbiting earth in the thermosphere?

the international space station

Temperature refers to:

individual molecules

Temperature in thermosphere would feel cool due to what?

low density

Northern and Southern Lights occur when:

high energy particles emitted from solar wind interact with earth’s magnetic field and emit photons of light

Aurora Borealis and Aurora Australis are found mostly near the poles where:

earth’s magnetic field concentrates solar wind particles

What are the compositional layers?

• homosphere

• heterosphere

Homosphere (3)

• inner atmosphere- surface to 80km

• gases evenly mixed

• includes troposphere, stratosphere, mesosphere

Heterosphere (3)

• outer atmosphere- 80km outwards

• includes thermosphere

• gases sorted into layers according to gravity and molecular weight

Ozone found in (2)

• stratosphere: (UV-absorbing ozone layer)

• troposphere: form of pollution

Ozone is increasing and is toxic to

people and plants

Stratospheric Ozone is:

naturally produced

Tropospheric Ozone

pollutant created by volatile organic compounds (VOCs) and sunlight

Ozone formation: step 1 and step 2

1. UV radiation absorbed by O₂, creating free oxygen

2. free oxygen combines with O₂ to form O₃

Ozone Depletion (3)

• chlorofluorocarbons (CFCs) are anthropogenic pollutants

• CFCs break down O₃ to O₂ into chlorine oxide (ClO)

  • as the ozone layer is depleted, more uv radiation reaches the surface

Free chlorine damages what?

the ozone layer

One Cl molecule can destroy how many ozone molecules?

100,000

When was the first Antarctic ozone hole first detected and when/ where does it form? (2)

• 1979

• forms every spring in southern hemisphere

What are the impacts of increased UV exposure at the earth’s surface? (3)

• cancer and suppressed immune systems

• reduced crop yields

• plankton destroyed in ocean

1987 Montreal Protocol (3)

• began CFC phase out

• CFC amounts have been declining

• recovery expected ~2050