Chp 13 Atmosphere Flashcards
What is the most polluting fossil fuel?
Coal
SO2
sulfur dioxide
What do SO2 emissions lead to?
Acid rain
What can happen to fish in acidified lakes?
Die of starvation due to the loss of their food sources
What gases are the atmosphere made up of?
78% nitrogen (n2)
21% oxygen (o2
1% other (including argon)
How many layers of the atmosphere are there and how do they differ?
four different layers. differ in temperature, density and composition.
Define atmosphere
the thin layer of gases that surrounds earth
What is a PERMANENT gas?
A permanent gas in the atmosphere remains at STABLE conditions
What were the dominant gases in Earths early atmosphere?
Carbon dioxide(CO2), Nitrogen (N2), carbone monoxide(CO), and hydrogen (H2)
What started the change in our early atmosphere to the our atmosphere today? (2.7 bill yrs ago)
The emergence of Autotrophic microbes that emit oxygen as a by product of photosynthesis.
What is the TROPOSPHERE?
The troposphere is the most BOTTOM layer of the atmosphere (0-10km)
In the troposphere, temperature declines the higher you go
What is the STRATOSPHERE?
Second layer of atmosphere. 11-50 km above sea level.
More dry and less dense than the troposphere. Contains UV radiation, blocking ozone.
Thermo sphere
Highest layer of earths atmosphere, 80-500km
In the mesophere temperatures ________ with altitude
Decrease
What is atmospheric pressure?
Force per unit of area produced by a column of air.
Atmospheric pressure ______ with altitude(in troposphere)
decreases
Why do mountain climbers have a hard time breathing the higher they climb?
Air pressure decreases the higher you go up. At the halfway point of mount everest for example, 50% of air molecules are below you. At mount everests peak, you are above two-thirds of air molecules in the atmosphere.
The gases in the stratosphere experience little VERTICAL MIXING, that is…
when substances(such as pollutants) enter the stratosphere, they tend to remain there for a long time.
Why is the ozone layer important? Where does it lie in the atmosphere?
Ozone greatly reduces the amount of UV radiation(which can damage living tissue and create DNA mutations). 17-30 km above sea level.
What is the RELATIVE HUMIDITY of air?
the ratio of water vapour in a volume of air, to the maximum amount it could potentially contain at a given temperature.
Why does humidity make it feel hotter than it is?
We sweat to cool our bodies down. When humidity is high, the air is holding nearly as much water as it can. So, that means our sweat evaporates slowly and the body cannot cool itself efficiently.
What is air mass?
a large volume of air that is fairly uniform internally, in temperature, relative humidity and air pressure
Why is it hottest at the equator?
Sunlight hits the equator directly(perpendicular angle), so the air absorbs less solar energy due to the shorter path through the atmosphere
What causes the change in seasons?
Because the earth is tilted, during a half of the year, as it travels through its orbit around the sun, the earths northern hemisphere faces towards the sun , while the southern hemisphere faces away from the sun (this is true conversely for the other half of the year). The hemisphere that faces towards the sun experiences direct sunlight, while the half away from the sun experiences indirect sunlight (less concentrated). Equatorial region is barely effected by this.
FRONT
the boundary between air masses that differ in moisture content and temperature, (where we typically experience the most active weather)
How do cold fronts cause thunderstorms and tornadoes?
A cold front displaces warmer air masses. The warm air rises, expands, and cools to form clouds that produce these thunderstorms.
Convective circulation
The rising of less dense, warmer air, creates vertical currents.
What is the urban heat island effect?
Cities often have temperatures that are hotter than surrounding suburbs and rural areas. Results from the concentration of heat generating buildings, cars, factories and people.
thermal inversion
the normal direction of temperature change is inverted. can cause air pollution to be trapped and move towards the ground, instead of diluting upwards
Dust dome
When heated air becomes trapped over cities due to thermal inversion, smog and particulate air pollution it carries becomes trapped as well
Hadley cells
A pair of convective air currents near the equator where surface air warms, rises, and expands. Releases moisture producing heavy rainfall
Ferrel cells/polar cells
lift air and create precipitation around 60 degrees latitute north and south. These interact with the earths rotation to produce global wind patterns.
Coriolis effect
When the north to south air currents of convective cells are deflected from a straight path. Effects the circulation of any freely moving fluit on the earths surface, but is not noticeable on a small scale.
how do dust storms occur?
when wind sweeps over bare, arid terrain sending huge amounts of dust aloft. the scale of these storms are worsened by unsustainable farming and grazing practices
aerosols
When sulfur dioxide reacts with water and oxygen, and condenses into fine droplets. Aerosols reflect sunlight back into space and cools the atmospher and the earths surface as a result.
give example of point source and non point source pollution.
point source: power plants and factories
non point source: many automobiles in a city
secondary pollutants
form when primary pollutants interact or react with constituents or components of the atmosphere
FOUR CATEGORIES OF POLLUTANTS OF GREATEST CONCERN (CEPA)
criteria air contaminangs
persistent organic pollutants
heavy metals
toxic air pollutants
CRITERIA POLLUTANTS
pollutants that are judged to pose great threats to human health
EXAMPLES OF CRITERIA POLLUTANTS
SO2,NO2, PARTICULATE MATTER, CO, ammonia NH3
PRIMARY POLLUTANTS
pollutants that are emitted in a form that can be directly harmful, or can react to form harmful substances
Persistent organic pollutants
Last in the environment dor long periods of time. Remain in environmental reservoirs and/or take a long time to break down
transboundary pollution
pollution that crosses borders
What are scrubbers?
devices that chemically convert or physically remove pollutants before they are released into atmosphere by smokestacks
what is the most common air quality problem?
smog
what is smog
unhealthy mixtures of air pollutants , often form over urban areas
What is the southern asian brown cloud?
a 3km thick layer of pollution that reduces sunlight by 10-15%, affects climate, kills thousands of ppl pr year
what are chloroflourocarbons(cfcs)?
Chemicals that attack ozone, they release chlorine atoms that split ozone
What is acid deposition
The deposition of acid/forming pollutants from the atmosphere onto earths surface. It is a transboundary pollution problem.
Includes acid rain, and atmospheric deposition (the wet or dry deposition of pollutants on land)
what ph level of rain is considered acidified
less than 5.1
How have so2 and NOx emissions changed? acid deposition?
so2 is lower
nitrous oxide is somewhat unchaged
acid deposition worse
How is indoor air pollution worse?
exposure to synthetic materials (insecticides, cleaning fluids, plastics, chemically treated wood)
What is the second leading cause of lung cancer in the developed world?
Radon gas
Volatile
easily evaporated at normal temperatures
