Envi Sci Flashcards
A colorless, odorless, tasteless, gaseous mixture
Air
is a mixture of mostly nitrogen and oxygen with traces of carbon dioxide, argon, water vapor and other minute components.
Air (earth’s atmosphere)
a blanket of air made up of a mixture of gases that surrounds the Earth and reaches almost 350 miles from the surface of the Earth.
Atmosphere
It absorbs energy from the Sun, recycles water and other chemicals, and works with the electrical and magnetic forces to provide a moderate climate
Atmosphere
Earth’s atmosphere (in order)
- Troposphere
- Stratosphere
- Mesosphere
- Thermosphere
- Exosphere
levels of the atmosphere can be identified according to general characteristics, such as temperature distribution and physical and chemical properties
Atmospheric layers
- extends from sea level up to 20,000 feet over the poles and to 55,000-60,000 feet over the equatorial regions
- where vast majority of weather, clouds, storms, and temperature differences occurs
- major component of the atmosphere
Troposphere
Temperatures within the troposphere
decrease with an increase in altitude (Lapse Rate) at a constant rate of 3.5 °F or 2 °C per 1000 ft increase in altitude
top most layer of the troposphere, which serves as a dividing region before the next layer
Tropopause
extends from the tropopause to a height of about 160,000 feet or about 30 miles
Stratosphere
Temperature in stratosphere
gets warmer with an increase in altitude; usually moving from a temperature of -76° F to about -40° F
extends from beyond the stratosphere to about 280,000 feet or from about 30 to 50 miles
Mesosphere
Temperature in mesosphere
increases but then it decreases at the top of the layer to about -130° F.
begins at about 50 miles up and extends to about 300 miles.
Thermosphere
Temperature in thermosphere
it increases depends on solar activity, but it is usually between 1,380° F and 2,280° F
- extends from about 10 to 30 miles in altitude.
- the Sun’s radiation reacts with the oxygen molecules and causes them to pick up a third atom, creating ozone.
- performs the very important function of shielding the Earth from ultraviolet and infrared radiation.
Ozonosphere
- begins at an altitude of about 25 miles and extends outward to about 250 miles
- Because of the interactions between atmospheric particles and the Sun’s radiation, there is a loss or gain in the electrons of the atoms and molecules, and thus the word “ion”.
Ionosphere
- body of air in motion due to difference in pressure
- has direction and speed
Wind
is defined as the direction from which the wind is blowing.
Wind direction
Results from uneven heating
Temperature
is the total energy of all molecules within a substance.
Heat
Four Ways to Transfer Heat:
Conduction
Convection
Advection
Radiation
a heated particle comes in contact with another particle, and the 2nd particle absorbs some of its heat
Conduction
heat transfer by vertical motion
Convection
lateral transfer of heat
Advection
heat energy from the sun
Radiation
The weight or push of gaseous molecules on the Earth’s surface
Atmospheric pressure
Any visible or invisible particle or gas found in the air that is not part of the original, normal composition.
Air pollution
Natural air pollution
Forest dires, pollen, dust storm
Unnatural air pollution
man-made; coal, wood and other fuels used in cars, homes, and factories for energy
Indicates whether pollutant levels in air may cause health concerns.
AQI: Air Quality Index
Sources of air toxics
Routine emissions from stationary sources
Mobile sources
Accidental releases
Forest fires
5 major pollutants
Carbon monoxide
Sulfur dioxide
Nitrogen dioxide
Particulate matter
Ground level ozone
•colorless, odorless
•produced when carbon does not burn in fossil fuels
•present in car exhaust
•deprives body of O2 causing headaches, fatigue, and impaired vision
Carbon monoxide
•produced when coal and fuel oil are burned
•present in power plant exhaust
•narrows the airway, causing wheezing and shortness of breath, especially in those with asthma
Sulfur dioxide
•reddish, brown gas
•produced when nitric oxide combines with oxygen in the atmosphere
•present in car exhaust and power plants
•affects lungs and causes wheezing; increases chance of respiratory infection
Nitrogen dioxide
•particles of different sizes and structures that are released into the atmosphere
•present in many sources including fossil fuels, dust, smoke, fog, etc.
•can build up in respiratory system
•aggravates heart and lung disease; increases risk of respiratory infection
Particulate matter
•at upper level, ozone shields Earth from sun’s harmful UV rays
•at ground level, ozone is harmful pollutants
•formed from car, power and chemical plant exhaust
•irritate respiratory system and asthma; reduces lung function by inflaming and damaging lining of lungs
Ground level ozone
Smog
•Combination of gases with water vapor and dust
•Combination of words smoke and fog
•Forms when heat and sunlight react gases (photochemical smog)
•Occurs often with heavy traffic, high temperatures, and calm winds
Effects of smog
•Limits visibility
•Decreases UV radiation
•Yellow/black color over cities
•Causes respiratory problems and bronchial related deaths
is an act promulgated by the Philippine Government to “protect and advance the right of the people to a balanced and healthful ecology in accord with the rhythm and harmony of nature.”
The Philippine Clean Air Act of 1999 or RA 8749
is one that takes place with no addition or removal of heat and with sufficient slowness so the gas can be considered to be in equilibrium at all times.
adiabatic process
Five mechanisms of deterioration have been attributed
to air pollution:
abrasion, deposition and removal, direct chemical attack, indirect chemical attack, and electrochemical corrosion
Factors That Influence Deterioration
Moisture, temperature, sunlight, and position of the exposed material are among the more important factors that influence the rate of deterioration.
six criteria air pollutants for which the US EPA has designated NAAQS
CO, Pb, NO2, O3, SO2, Particulate Matter
