Chapter 1-Earth & its atmosphere

Question 1

Name the systems of the planet. How do they interact with eachother?

Answer 1

Atmosphere
Lithosphere
Hydrosphere
Cryosphere
Biosphere
The systems interact with each other through many processes (e.g., hydrological cycle, carbon cycle, human activities,etc)

Question 2

To where does the gaseous part of the atmosphere extend to?

Answer 2

Gaseous part extends from surface to exosphere (fading into space)

Question 3

What is the lithosphere of the earth?

Answer 3

The solid earth crust

Question 4

What is the hydrosphere of the earth?

Answer 4

oceans, lakes, rivers, ice and snow (Ice and snow separately form the cryosphere)

Question 5

Define the Biosphere of the planet?

Answer 5

Plants, animals and humans

Question 5

How does the cryosphere differ from the hydrosphere?

Answer 5

Cryosphere: Ice and snow separately form the cryosphere

Hydrosphere: oceans, lakes, rivers, ice and snow

Question 6

How many KM separate the Sun and Earth?

Answer 6

Nearly 150 million

Question 7

How is the earth’s weather affected by the Sun despite the 150 million km distance?

Answer 7

Solar radiation drives the Earth’s weather

Question 8

Define the atmosphere of the planet

Answer 8

A thin film of gases and tiny particles (aerosols) surrounding the earth

Question 9

How is the atmosphere essential for life?

Answer 9

-It is a thin film of important gasses and tiny particles like Oxygen (O2), Carbon Dioxide (CO2), water(H2O)

-It shields us from ultraviolet radiation, etc.

Question 10

True or false?
The atmosphere is more than 100 km deep & the weather is contained in most of it.

Answer 10

FALSE
The atmosphere is more than 100 km deep (fading into space), but most of the weather is contained in the lowest layer, from the surface up to 10 - 16km

Question 11

When was the Planet Earth born and what did its first atmosphere consist of?

Answer 11

-Planet Earth was born about 4.6 billion years ago

-First atmosphere consisted mainly of gaseous hydrogen (H2) and helium (He), which escaped into space due to high temperatures at the early times.

Question 12

How is outgassing bound to earth?

Answer 12

Outgassing” of lava, ashes, gases from volcanoes supply water (H2O), carbon dioxide (CO2), and nitrogen(N2) are bound to earth by its gravitational field

Question 13

What was the mean global surface air temperature at the early phase of planet earth?

Answer 13

Mean global surface air temperature between 85 - 110°C (compared to~15°C now)

Question 14

What are the consequences of planet cooling, water vapor condensing to form clouds and precipitation?

Answer 14

*Formation of oceans
*CO2 stored in oceans and sedimentary rocks (e.g.,limestone)
*N2 begins to dominate the air composition

Question 15

How does life formed about 2 billion years ago?

Answer 15

*Photosynthesis by plants produces molecular oxygen(O2)
*Through photochemical reactions, ozone (O3) shield forms, protecting and enabling life on land.

Question 16

What are the main atmospheric constituents of the modern phase of planet earth?

Answer 16

Main atmospheric constituents are nowadays N2 (78%), O2 (21%) & others up to ~80 km altitude

Question 17

Where is O3 mostly found in atmosphere?

Answer 17

97 % of O3 is in upper atmosphere, where it forms “naturally”

Question 18

What is the importance of ozone (O3)?

Answer 18

The “Ozone layer” shields the Earth from harmful ultra violet radiation.

Question 19

What is the ozone “hole”?

Answer 19

Layer was/is being depleted near poles by Chloroflurocarbons (CFCs); a major source of CFCs came from spray cans and refrigerants

Question 20

What is the primary ingredient to photochemical smog (human influence)? What are the symptoms/damages?

Answer 20

Ozone (O3)
Irritates eyes and respiratory tract (lungs), damages vegetation

Question 21

What is the importance of CO2 in the planet?

Answer 21

Used by plants for photosynthesis
*Plants grow and produce oxygen (O2) alongside sugars (glucose,etc.)

Absorbs a portion of the Earth’s outgoing long-wave radiation (infrared), and radiates it back to the surface
*important greenhouse gas

Question 22

Is the average concentration of CO2 increasing or decreasing? Since when?

Answer 22

Average concentration is annually increasing since industrialization

Question 23

What is the importance of water vapour (H20) for our planet?

Answer 23

-Highly variable concentration
-Stores latent heat
-V important greenhouse gas

Question 24

Why is water vapour (H20) a highly variable concentration?

Answer 24

*From negligible to 4 % by volume
*Produced by evaporation/sublimation; lost by condensation/deposition (part of hydrological cycle)
*Condenses to form cloud droplets

Question 25

How is water vapour (H20) produced and lost?

Answer 25

Thanks to part of the hydrological cycle (one of the various ways the planet systems interact with each other)
-Produced by evaporation/sublimation
-Lost by condensation/deposition

Question 26

Why is storage of latent heat from water vapour important for the atmosphere?

Answer 26

*When latent heat is released in clouds it helps to drive atmosphere’s general circulation
*Feeds thunderstorms and hurricanes with energy

Question 27

What kind of activities emit particles (aerosols and pollutants) into the atmosphere?

Answer 27

Natural and human activities

Question 28

Define aerosols

Answer 28

Suspended tiny (invisible) dust, salt, ash, soot and organic particles

Question 29

True or False?
Aerosols are just considered pollutants

Answer 29

False
-High aerosol concentrations affect adversely the health of humans and animals (depends also on the types of aerosol particles)
-Aerosols are also important for cloudformation and not just “pollutants”!

Question 30

Define high aerosol concentration

Answer 30

High particulate matter mass per unit volume of air

Question 31

Name some examples of gaseous pollutants

Answer 31

-Sulfur dioxide (SO2)
-Nitrogen oxides (NO, NO2)
-Ozone (at surface)
-Volatile hydrocarbons (VOCs)

Question 32

What are primary aerosol particles? Give examples

Answer 32

Directly emitted in particulate form

*Biogenic/natural (mineral dust, sea salt, volcanic ash, forest fires,vegetation,…)

*Anthropogenic (combustion of fossil fuels, biomass burning, traffic emissions, industry)

Question 33

What are secondary aerosol particles? Give examples

Answer 33

Formed in the air by gas-to-particle conversion processes
*Example: oxidation of volatile organic precursors (by O3, ·OH, ·NO3,etc.)

Question 34

How are new aerosol particles formed?

Answer 34

From gaseous vapours that undergo gas-to-particle conversion (Friedlander, 1977

Question 35

What are typical aerosol particle diameters?

Answer 35

100 - 400nm
-for reference: 1 mm = 1000μm & 1 μm = 1000nm
-human hair is 50μm

Question 36

True or False?
Water vapour does not vary with location and time

Answer 36

False
Water vapour varies with location and time. It usually accounts for less than 4 % in an air volume near the surface. At typical value is 1 % of water vapour

Question 37

What is the only major substance that is found naturally as gas, liquid and solid?

Answer 37

WATER
-gas (water vapour)
-liquid (water; cloud, rain droplets)
-solid(ice)

Question 38

True or False
There are only 2 effective greenhouse gases

Answer 38

False
Water vapour and carbon dioxide (CO2) are important greenhouse gases. Although some much less abundant trace gases are also effective greenhouse gases

Question 39

What is the difference in role of ozone in different systems of the atmosphere?

Answer 39

Ozone (O3) in the stratosphere protects life on the ground from harmful solar UV radiation.
At the surface, ozone is a harmful pollutant and a main ingredient of photochemical smog