chapter 3 Flashcards
what does atmosphere do
protect us from hostile radiation and particles from the sun and beyond
components of air
a simple misture of gases N2 (78%), O2 (21%), others (1%), and water vapor H2O (0 to 4%), CO2 (0.0035%) that is naturally odourless colourless, tasteless, and formless, blended so thoroughly that it behaves as if it were a single gas
how big is the atmosphere
480 km above Earth’s surface
exosphere
outer sphere, lightweight hydrogen and helium atoms with some oxygen atoms and nitrogen molecules, weakly bound by gravity as far as 32 000 km from earth, beyond the thermopause
Air pressure
pressure produced by the motion, size, and number of gas molecules in the aire and exerted on surfaces in contact with the air
why is the air denser near Earth’s surface
because gravity compress the air downward
what percentage of the atmosphere remains above an altitude of 50 km
only 0,1%
Heterosphere
80 to 480 km altitude, a zone of the atmosphere above the mesopause, includes the ionosphere, less than 0,001% of the atmospheres mass, because of gravity the gases or not uniform, hydrogen and helium at the top, and oxygen and nitrogen at the bottom
Homosphere
earths surface to 80 km altitude, composed of an even mixture of gases, nitrogen, oxygen, argon, carbon dioxide, and trace gases, ozone layer from 19 to 50 km above sea level
Nitrogen
78% percentage by volume, unreactive and unavailable, originating principally from volcanic sources, integrated into our bodies through compounds in food ,sinks; nitrogen fixation, lightning
Oxygen
21%, reacts via oxidation, by-product of photosynthesis, one-fifth of the atmosphere, forms compounds that compose about half of earths crust, sinks; weathering, combustion, aerobic decomposition
Carbon dioxide CO2
natural by-product of life processes, cellular respiration, wildfires, combustion of fossil fuels, small percentage in atmosphere, the CO2 percentage has increased as a result of human activities, principally the burning of fossil fuels and deforestation, greenhouse gas, sinks; photosynthesis, dissolution in oceans
Argon
comes from slow accumulation over millions of years, less than 1% of the homosphere
Methane
0,00018% second greenhouse gas, human activity
Temperature
measure of the average kinetic energy of individual molecules
Heat
is the flow of kinetic energy from one body to another resulting from a temperature difference between them, depends on density or mass of a substance; where little density or mass exists, the amount of heat will be small
why is the temperature high in the atmosphere but not hot
because the density is low, it will feel cold because the number of molecule is not great enough to transfer heat to our skin
Thermosphere
80 to 480km in altitude, contains the functional ionosphere layer
When less active sun, the thermopause may low in altitude form 480km to 250km, when period of more active sun, the outer atmosphere can go up to 550km, where it can create frictional drag on satellites in low orbit
The temperature rise sharply to 1200degree Celsius and higher, it raise with altitude because its direct contact with high energy solar radiation
Mesosphere
50 to 80km in altitude, within the homosphere, mesopause; mesospheres outer boundary, coldest portion of the atmosphere -90degree celsius, but temperature may vary 25-30degree celsius, because of the extremely low pressures, low density of molecules
Noctilucent cloud
a rare, shining band of ice crystals that may glow at high latitudes long after sunset, where cosmic and meteoric dust act as nuclei for the formation of ice crystal
Stratosphere
18 to 50km in altitude, temperatures increase with altitude, from -57degree celsius at 18km to 0degree celsius at 50km, stratopause; stratospheres outer boundary, ozone layer
Troposphere
Final layer encountered by incoming solar radiation, supports life and the biosphere, and its the region of principal weather activity, 90% of the total mass of the atmosphere, temperature is -57degree celsius, tropospheres upper limit is tropopause, but exact altitude depends on season, latitude, and surface temperatures and pressures
what the order of the component of the atmosphere
homosphere than heterosphere
troposphere, stratosphere, mesosphere, thermosphere
Normal lapse rate
the average rate of temperature decrease with increasing altitude in the lower atmosphere; an average value of 6.5degree celsius
Environmental lapse rate
the actual rate of temperature decrease with increasing altitude in the lower atmosphere at any particular time under local weather conditions
Blue Jets and Red Sprites
electrical discharges above active thunderstorms
what does the Ionosphere and ozonosphere do
remove most of the harmful wavelength of incoming solar radiation and charged particles
Ionosphere
50km outwards to about 1000km, absorbs cosmic rays, gamma rays, X-rays, and shorter wavelengths of ultraviolet radiation, changing atoms to positively charged ions, aurora
Ozonosphere
or ozone layer, 20 to 50km above the surface, absorbs the shorter wavelengths of ultraviolet UV radiation and convert them into heat energy
Density
mass over volume, the higher you get the less dense the air get
name some natural pollutants and there effects
volcano (sulfure oxide, particulates), wildfires( carbon monoxide and dioxide, nitrogen oxide, particulates), plants (hydrocarbons, pollens), plants decomposing (methane, hydrogen sulfide), soils (dust, virus), and ocean (salt spray and particulates)
Atmospheric aerosols
microscopic particles, physical characteristic, dark coloured is warming, light coloured is cooling, enhance cloud formation, low residence time, spatially variable
Temperature inversion
warmer air on the top, mixing blocked, pollution trapped beneath inversion, a reversal of the normal decrease of the temperature with increasing temperature; can occur anywhere from ground level up to several thousand meters; functions to block atmospheric convection and thereby trap pollutants
Anthropogenic pollution, name the gases
carbon monoxide, photochemical smog (interaction of automobile exhaust and UV radiation causes photochemical reactions), industrial smog and sulphur oxides, and particulates
Acid rain and its effects
wet and dry deposition from the atmosphere containing higher than normal amounts of nitric and sulphuric acids, effects; surface waters and aquatic animals, forests, ecosystem impairment, materials or building damage, visibility, human health
Pollutants
natural or human-caused gases, particles, and other substances in the troposphere that accumulate in amounts harmful to humans or the environment
Anthropogenic atmosphere
Earth’s future atmosphere, so named because humans appear to be the principal causative agent
whats the largest source of air pollutant and what is main source
carbon monoxide, by vehicule
Photochemical smog
the interaction of sunlight and the combustions products in automobile exhaust
Volatile organic compounds (VOCs)
produced by the combustion of gasoline
smog
a combination of the word smoke and fog, generally used to describe photochemical smog and volatile organic compounds
PAN
peroxyacetyl nitrate, can damage agricultural crops or forest, no human health effect
Industrial smog
air pollution associated with coal-burning industries; it may contain sulfur oxides, particulates, carbon dioxide, and exotics
Black carbon
produce in small village, aerosol with devastating health effects
