(COMPLEX SYSTEM) What is weather & climate?
- Weather: Short-lived, local patterns temperature and precipitation due to circulation of the troposphere.
- Climate: Long term patterns of temperature and precipitation.
What is Energy and the Greenhouse effect?
- Most solar energy reaching Earth is near infrared.
- Greenhouse effect: CO2 and other "greenhouse" gases prevent infrared radiation from escaping the Earth's atmosphere.
- Greenhouse gases: water vapor (H2O), carbon dioxide (CO2), methane (CH4), nitrogen oxides (NOx ), and chlorofluorocarbons (CFC)
Define latent heat:
Energy stored in water vapor.
What is the El Nino and the Coastal Zone?
- *it occurs when its warm surface waters in Pacific Ocean move back & forth between Indonesia and South America.
- *Every 4-7 years
- cells replace the normally low atmospheric pressure of the western Pacific
What is the effects of El Nino?
- *Drought in Africa, Australia, & Indonesia
- *Flooding in California, Ecuador, Peru, Tahiti
- *Hawaiian Hurricanes only during El Nino yrs.
- *Decreases Atlantic hurricane actvity
- *Reduces forest fires in Arizona, Texas, & N.M
- *Reduces tornadoes
- *Produces better citrus & vegetable crops
- *Improves fishing off California because of luke warm water
What is Natural Climate Variability?
- *Climates shift on scales of decades, centuries or millennia.
- *revolutionized our understanding of climate history.
- *Analyze oxygen, carbon dioxide, volcanic eruptions
- *Oxygen Isotopes
- Cold years- lighter isotope evaporates more easily than water with heavier isotope.
- *Vostok ice core-420,000
What is Milankovitch cycles?
- Variations in the Earth's orbit cause climate change.
- A) Eccentricity: every 100,000 years the Earth's orbit becomes more elliptical and then returns back to more of a circle.
- B) Obliquity: The tilt of the Earth changes from ~21.5 to ~24.5 every 41,000 yrs.
- C) Precession: Or the wobble of the Earth's axis occurs during a 26,000 yrs. period.
Define Carbon Dioxide:
- Carbon Dioxide: emissions have doubled from 1970 to 2010.
- *fossil-fuel burning is the major human caused source of carbon dioxide.
Define Nitrous Oxide:
- vehicle engines, agriculture processes are major sources.
- *The relative effects of each greenhouse gas can be seen by converting them CO2 Equivalents.
- ruminants and rice paddies are sources
- *Microbial decay in anoxic conditions.
Whats an option for Controlling Emissions?
- Carbon Trading: legal limits on emissions are set & countries that want to emit more must purchase emissions credits from others.
- *A global market for trading carbon emissions has already developed.
- *This market may grow $500 billion a year by 2050.
What is Criteria Pollutants?
- *U.S. Clean Air Act (1963) designated six major (conventional or criteria pollutants) for which maximum ambient air levels are mandated.
- *Sulfur Dioxide, *Nitrogen Oxides, *Carbon Monoxide, *Ozone,*Lead,Particulates.
What is Anthropogenic Air Pollution?
- Primary Pollutants: released directly from the source.
- Secondary Pollutants: converted to a hazardous formafter entering the air & mixing with other air components (ie. acid rain)
- *Fugitive Emissions: do not go through smokestack.
- *Dust from strip mining, rock crushing, building construction/destruction
What is sulfur dioxide?
- fossil-fuel combustion (coal & oil) & smelting of sulfide ores.
- ((corrosive gas which reacts with water vapor in the air to cause acid rain))
What is Nitrogen Oxides?
reactive gases formed when nitrogen is heated above 650C in the presence of oxygen, or when nitrogen compounds are oxidized by bacteria.
What is Lead?
- *Many toxic metals occur as trace elements in fuel especially coal.
- *It is 2/3 of all metallic air pollution
- *Neurotoxin: Binds to brain cells.
What is the other Metallic Pollutants?
Mercury and Halogens
What are the Mercury Pollutants?
- *70% from coal-burning power plants, smelting, waste incineration.
- neurotoxin, 75% of human exposure comes from eating fish.
- exposure attributed to contaminated tuna
- bacteria responsible for converting airborne mercury to methyl mercury
What is Halogens Pollutants?
- •(Fluorine,Chlorine, Bromine)
- (chlorofluorocarbons) release chlorine and fluorine in the stratosphere, which
- deplete ozone layer.
- banned in developed countries but still used elsewhere in propellants and
What is Particulate Matter?
- *Aerosol: solid particles or liquid droplets suspended in the atmosphere
- *atmospheric aerosols are usually called particulate material
- ash, soot, lint, smoke, pollen, spores, etc.
- *reduce visibility
- *smaller than 2.5 micrometers
What is acid Precipitation?
- Deposition of wet acidic solutions or dry acidic particles from the air
- *Unpolluted rain generally has pH of 5.6.
- •Carbonic acid from atmospheric CO2
- *H2SO4 and HNO3 from industrial and automobile emissions
- are cause of acid precipitation.
- *Aquatic effects are severe, as pH of 5 in freshwater lakes disrupts animal reproduction and kills plants, insects and invertebrates. Below pH 5, adult fish die.
How can you control air pollution?
- •Reducing Production
- *Conservation –by reducing electricity consumption, insulating buildings and providing energy
- saving public transportation
- *Particulate Removal
- •Remove particles physically by trapping
- them in a porous mesh which allows air to pass through but holds back solids.
- *•Electrostatic Precipitators-fly ash particles pick up electrostatic charge as they pass between large
- electrodes in waste stream, and accumulate on collecting plate
What is Renewable Energy Resources?
- *energy resources that can be replaced at
- a rate equal to, or faster than they are consumed.
- **This includes solar, water, wood, wind,
- tidal forces, and geothermal.
What is Nonrenewable Energy Resources?
- *energy resources that can not be replaced
- at a rate equal to, or faster than they are consumed.
- *This includes oil, natural gas, coal, and
- radioactive material.
What is the rank of coal?
Peat → Lignite → Subbituminous → Bituminous → Anthracite
What is Lignite coal?
- It has undergone low degrees of
- metamorphism; therefore, it has a high volatile content.
What is Anthracite coal?
- It has undergone high degrees of
- metamorphism; therefore, it has a low volatile content and burns “hot and
What is Hydrocarbon Compounds?
- Chemical compounds that consist of
- hydrogen and carbon.
- *Petroleum, also known as crude oil, is a
- hydrocarbon with the chemical formula ranging from C5H12 to C18H38
What is Tar sands?
- They are composed of sand and shale particles coated with bitumen, a viscous mixture of
- long chain hydrocarbons.
*They have to be mixed with steam to extract the bitumen, which is then refined.
*Creates toxic sludge, greenhouse gases, contaminates water, and destroys boreal forest in Canada where most of reserves are.
What is oil shale?
*sedimentary rock rich in kerogen (organic chemical compound).
- *Large reservoirs of oil shales
- occur in western U.S.
*Might yield several trillion gallons of oil
- *Mining is expensive, uses vast quantities of water contributes to air and water
- pollution, and produces huge quantities of waste.
What is nuclear fission?
- *Most commonly used fuel is U235, a naturally occurring radioactive isotope
- of uranium.
*When struck by neutrons, radioactive uranium atoms undergo nuclear fission
, releasing energy and more neutrons.
*Triggers nuclear chain reaction
What are pressurized water reactors (PWR)?
- *70% of nuclear power plants
- *Water is circulated through core to absorb heat from fuel rods and then pumped to
- steam generator where it heats a secondary loop
*Steam from secondary loop drives high-speed turbine producing electricity.
What is nuclear fusion?
- Energy released when two smaller atomic nuclei fuse into one large nucleus.
- Energy in sun, hydrogen bombs.
What is Passive Solar Heat?
using absorptive structures with no moving parts to gather and hold heat
What is Active Solar Heat?
pump heat-absorbing medium through a collector, rather than passively collecting heat in a stationary object
What do the reformer do?
- •releases some pollutants, but far below
- conventional fuel levels.
What are the unwanted effects of dams?
- *Human Displacement
- *Ecosystem Destruction
- *Wildlife Losses
- *Large-Scale Flooding due to Dam Failures
- *Herbicide Contamination
- *Evaporative Losses
- *Nutrient Flow Retardation
What is Tidal Stations?
*tide flows through turbines, creating electricity
•Requires a high tide/low-tide differential of several meters
What is Energy Efficiency?
*a measure of energy produced compared to energy consumed.