Lesson 1: Atmospheric Composition

what is the atmosphere?

• what percentage is the atmosphere of the earth’s radius?

• what percentage of air molecules are located in a section that is about 0.25% of the earth’s radius

• made up mostly of () but also has some airborne solid or liquid particles that are called ()

• thin layer surrounding earth

• 1% of earth’s radius

• 90% of air molecules

• made up mostly of gases but also has some airborne solid or liquid particles that are called aerosols

describe what the gases are like in the atmosphere?

• mostly trans… to…but typically absorb (u), (i), and/or (m)

• mostly transparent to visible radiation (light) but typically absorb ultraviolet, infrared and/or microwave radiation

what is a solid?

• state of matter with a fixed shape and a fixed volume

• molecules are tightly compressed (squeezed together)

what is a liquid?

• what is the volume and shape like?

• how do the molecules move?

• state of matter with a definite volume that flows freely and takes the shape of its container (variable shape) but does not expand to fill it like a gas

• molecules are loosely bound and move past each other easily but stay close together so the volume stays constant

what is gas?

• fundamental state of matter that has () and ()

• how do the particles move?

• compressibility?

• fundamental state of matter that has no fixed shape and no fixed volume

• free-moving particles

• can be easily squeezed into a smaller space

what is aerosol?

• mixture of () particles or () drops floating…OR….

• (), (), OR () matter (aka…)

• mixture of solid particles or liquid drops floating in the air or another gas

• small, solid OR liquid matter (aka. particulates)

• in our atmosphere

what are examples of larger particles?

• r

• d

• f

• s

• i

• c

• rain

• drizzle

• fog

• snow

• ice crystals

• cloud droplets

what is an atom?

• basic building…

• () and () at its nucleus, () in orbit

• basic building block of matter

• protons and neutrons at its nucleus, electrons in orbit

what is a molecule?

• group of at least…

• group of at least two atoms bonded together

most gases in the atmosphere are?

dia…

• diatomic molecules (N2 or O2)

• 99% of the air molecules are diatomic molecules

what is an ion and how are they created?

• atom or molecule with u…

• ions are created if () or () travels through the air and () apart the molecules

• ions are not electrically () or () apart

• atom or molecule with unequal # of protons (+) and electrons (-)

• ions are created if high-energy sunlight or lightning travels through the air and breaks apart the molecules

• ions are not electrically balanced or broken apart

what are sources?

they produce gases

what are sinks?

they deplete (remove) gases

what are permanent gases?

• permanent gases that have () because their rates of production and removal are () over long periods

• permanent gases that have constant concentration because their rates of production and removal are balanced over long periods

• what does this tell us about the sources and sinks?

• the sources and sinks are in a steady state of equilibrium (BALANCED)

• permanent gases such as nitrogen, oxygen, argon, trace gases remain consistent over time and they make up most of the atmosphere

what are variable gases?

• concentration?

• sources and sinks?

• variable gases that have changing concentration (change significantly over time and place)

• the sources and sinks are not balanced (and variable)

• what does this mean about the sources and sinks, and what are examples?

• the sources and sinks are not balanced (and variable - go up or down)

• sources: processes such as animal breathing and burning fossil fuels can add gases into the air such as CO2

• sinks: processes such as plants absorbing CO2 during photosynthesis

what are examples of permanent gases?

• ni

• o

• a

• ne

• he

• k

• hy

• nitrogen (78%) - It's an odorless, transparent gas, very stable, so it's non-reactive, and that's the main ingredient of our atmosphere.

• oxygen (21%)

• Argon, Neon, helium. krypton, hydrogen (1%)

what are sources and sinks for nitrogen?

• sources: decay…, vol…

• sinks: soil…

• sources: decaying plant and animals, volcanoes

• sinks: soil bacteria because they fixate the nitrogen

what are the sources and sinks for oxygen?

• sources: photo…

• sinks: res…, de…, ox…

sources: photosynthesis in plants

sinks: respiration, decay, oxidation

what are examples of variable gases?

• water…

• carbon…

• oz…

• water vapor

• carbon dioxide

• ozone

what is water vapor?

• ()-()%, highly…

• most…

• 0 to 4% (highly variable)

• most abundant variable gas

what is carbon dioxide?

• ()% and…

• concerns about…

• 0.039% and rising

• concerns about climate change if there is too much greenhouse gases released

what is ozone?

• highly (), () gas

• upper atmosphere: protects…

• occurs naturally in…

• highly variable, reactive gas

• upper atmosphere: protects life from UV light

• occurs naturally in sunlight

what are greenhouse gases?

• water…, carbon…, and meth… absorb () emitted by the () and () some of the () back down

• keep the temperature () warmer than otherwise would be

• acts as a…

• water vapor, carbon dioxide, and methane absorb infrared radiation emitted by the earth and re-radiate some of the infrared radiation back down

• keep the temperature 30 degrees C warmer than otherwise would be

• acts as a blanket

what is the greenhouse effect?

• () passes through the atmosphere and () earth’s surface

• the surface releases () which () gases absorb and (), trapping () and warming earth

• Sunlight passes through the atmosphere and heats Earth's surface.

• The surface releases infrared (IR) radiation, which greenhouse gases (CO₂, H₂O, O₃) absorb and re-radiate, trapping heat and warming Earth.

what are some properties of water vapor?

• water vapor is… why?

• () air can contain more water vapor than () air, why?

• water vapor is invisible because it has no color and cannot be seen by the human eye (when you see steam you are looking at tiny liquid water droplets or ice crystals not the gas itself)

• warm air can contain more water vapor than cool air because heat gives the molecules more energy to spread out and stay airborne

how is it important to meteorology?

• leads to the development of () and () and how do they form?

• () = energy () or () when H20 changes state

• leads to the development of clouds (water vapor condensing into liquid drops or ice crystals to form clouds) and precipitation (heavy drops fall to the ground as rain, snow, or sleet when they grow too heavy to stay aloft)

• latent heat = energy released or absorbed when H20 changes state

what is water vapor’s main source?

• e…

• this process () latent heat, () surroundings

• evaporation (liquid to gas)

• this process absorbs latent heat, cooling surroundings

what is water vapor’s main sink?

• c…

• this processes () latent heat, () surroundings

• condensation (gas to liquid)

• this process releases latent heat, warming surroundings

what is steam?

() unlike water vapor

when water vapor () and () liquid drops otherwise known as ()

cloud that forms when…

• visible unlike water vapor

• when water vapor condenses and forms liquid drops otherwise known as clouds

• cloud that forms when moisture cools

at what altitudes and latitudes would the highest water vapor concentrations be observed?

• right near the…

• what kind of climates? towards the ()/()

• right near the ocean surface (right above sea level) because of the evaporation

• warmer climates (towards the equator/tropics)

what are results of water vapor changing state between solid, liquid, and gas?

rain that can be identified as hurricanes, thunderstorms, fog, snow, etc

what is the main source of energy for thunderstorms, hurricanes, etc?

water vapor

how does water vapor get to the atmosphere and how long does it usually stay in the atmosphere?

evaporation mostly from the oceans

• 10 days

How can you get 40 inches of rain out of an atmosphere that only holds about up to 2 inches worth of rain?

• horizontal…

• horizontal wind that keeps bringing the moist air in and that gets lifted typically from a warm ocean, and then it rains

what does water vapor produce, reflect, and absorb?

• produces: c…

• reflects: solar…

• absorbs: inf…

• produces: clouds

• reflects: solar radiation back to space

• absorbs: infrared radiation

how do clouds affect temperature?

during the day?

during the night?

• clouds make it cooler during the day because it reflects the sunlight

• clouds make it warmer during the night

what is the leading cause of fatal general aviation accidents?

IMC (instrument flight conditions)

• clouds or fog because u could be flying into a mountain or terrain and not see where you are going

what are sources of carbon dioxide?

• res…

• com…

• vol…

• de…

• respiration

• combustion

• volcanic eruptions

• decay

what are sinks of carbon dioxide?

• photo…

• photosynthesis (by plants, mostly phytoplankton)

why is carbon dioxide concentration increasing with time?

• human activities that release stored carbon into the atmosphere faster than natural Earth systems can absorb it

what are positive results of increasing carbon dioxide?

• more…

• colder areas…

• more plant growth

• colder areas of earth are livable

what are negative results of carbon dioxide increasing?

• raised…

• changed…

• raised sea level

• changed climate patterns

why do we have an annual cycle of carbon dioxide?

• northern hemisphere?

• fall and winter?

• spring and summer?

• The Northern Hemisphere has so much more continental land areas so during our spring and summer, There's a lot more photosynthesis going on on the Earth than during the Northern Hemisphere winter— fall and winter.

• also temperature of our oceans - seasonal changes in plant growth

what do climate models show?

• doubling of…

• doubling of carbon dioxide, 1-3 degrees C doubling the amount of CO2 every 50 years

if you add more (), the () gets warmer, then you might have more () in the air, and that could give you more () and more (), which could () the warming.

if you add more carbon dioxide, the Earth gets warmer, then you might have more water vapor in the air, and that could give you more cloud formation and more reflection of sunlight, which could offset the warming.

what are the positive things about ozone?

• occurs (), absorbs…

• protects against (), loss of…

• occur naturally, absorbs harmful ultraviolet light from sun

• protects against skin cancer, loss of sensitive crops such as rice, etc

• ONLY POSITIVE IN UPPER ATMOSPHERE

what are negative things about ozone, specifically tropospheric ozone?

• manmade () can deplete…

• it also forms chemically in cities that have a lot of () in the air, and the sunlight () with the pollutants and with the () creates ozone

• why is it bad, what will it cause?

• NEGATIVE IN LOWER ATMOSPHERE

• One manmade chlorofluorocarbon (CFC) molecule can deplete

  thousands of O3 molecules

• it also forms chemically in cities that have a lot of pollutants in the air, and the sunlight interacting with the pollutants and with the oxygen creates ozone.

• That's bad because ozone is highly reactive, and so it will cause eye irritation, skin irritation, lung irritation. - YOU WANT LESS OZONE IN POLLUTED CITIES

why do we have an ozone hole in the southern hemisphere during the spring (sep-oct)?

• what kind of presence of ozone do we have in the SH and why?

• what is destroyed and what is formed that can destroy the ozone?

• what is another chemical that destroys more ozone in the SH more than anywhere else?

• there is low presence of ozone in the SH because the destruction of ozone by uv light is much more rapid if you have clouds and during sep-oct, it gets really cold that you have the polar stratospheric clouds that destroy the ozone molecules

• CFCs destroy more ozone in the SH more than anywhere else

what is the size of aerosols? are they visible? do they create or reduce visibility?

• aerosols are microscopic and are barely visible

• they reduce visibility (create haze)

what are examples of aerosols?

• du

• cl

• pol

• sea

• as

• dust

• clay

• pollutants

• smoke

• sea salt

• ash

why do aerosols fall slowly?

• wing drag so the smaller the particle, the slower it will fall

what do aerosols act as for condensation?

what about in other cases such as freezing? what two clouds are produced?

• act as nuclei

• water clouds and ice clouds

can aerosols affect aircraft performance?

• causes reduced…

• volcanic ash can…

• will accumulate inside…

• causes reduced visibility due to haze

• volcanic ash can strip paint off a plane

• will accumulate inside the air intakes of your engine

why do aerosols remain airborne?

• size?

• currents?

they are extremely small and light, so upward air currents easily keep them afloat.