CH 20 - Ozone Depletion
Composition of garbage in US
29% paper 14% food scraps 13% yard trimmings 12% plastics 9% metals 8% rubber and leather
The significance of NOx and SO2 as precursors of acid rain
acid rain, originates from the combustion of fossil fuels. When coal, oil, or other fossil fuels are burned, acid rain precursors--mainly nitrogen oxides (NOx) and sulfur dioxide (SO2)--are emitted into the atmosphere. Once in the atmosphere, NOx and SO2 are transformed into nitric acid and sulfuric acid and fall back to earth through both wet deposition such as rain, snow, fog, cloud water, and dry deposition of acids attached to particles, gases and aerosols.
Possible alternatives to CO2 reductions to cope with global warming
Forego Fossil Fuels Move Closer to Work—Transportation is the second leading source of greenhouse gas emissions in the U.S. (burning a single gallon of gasoline produces 20 pounds of CO2) Stop Cutting Down Trees
How waste treatment has changed on Long Island in last 20 years
1986 1995 Landfilled 83 0 Transported off LI 13 20 Recycled 0.8 35 WTE Incineration 2.5 45 Long Island closed the last landfill 1990 due to groundwater contamination concerns
Logistic growth curve - importance of knowing inflection point
Assumptions 1) A population can be described simply by its total # 2) Therefore, all individuals are equal 3) The environment is constant
Know how photochemical and sulfurous smog is formed
Photochemical oxidants result from atmospheric interactions of nitrogen dioxide and sunlight Most common is ozone—O3 Colorless gas with slightly sweet odor Very active chemically, oxidizes or burns Beneficial in the upper atmosphere Smog mixture of smoke and fog that produced unhealthy air Two major types Photochemical smog—LA-type smog or brown air Directly related to automobile use Sulfurous smog—London-type smog, gray air, or industrial smog Produced by combustion of coal or oil
Sources of contamination - point vs. non-point
Point sources are distinct and confined,such as pipes from industrial and municipal sites thatempty into streams or rivers. In general,point source pollutants from industries are controlledthrough on-site treatment or disposal and are regulated by permit Nonpoint sources ,such as runoff, are diffused andintermittent and are influenced by factors such as landuse, climate, hydrology, topography, native vegetation,and geology. Common urban nonpoint sources includerunoff from streets or fields; such runoff contains allsorts of pollutants, from heavy metals to chemicalsand sediment
Planning within a political context, balancing rights of individuals against needs of society
our society has formal planning processes for landuse. These processes have two qualities: a set of rules(laws, regulations, etc.) requiring forms to be filled outand certain procedures to be followed; and an imaginativeattempt to use land and resources in ways that are beauti-ful, economically beneficial, and sustainable. planning is a social experiment in which we all partic-ipate. Planning occurs at every level of activity, from a garden to a house, a neighborhood, a city park
Where and when has ozone depletion been observed?/Why are polar regions important in the documentation of ozone depletion?
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What is ozone?/the ozone layer?/how does it form?
A form of oxygen in which three atoms of oxygen occur together (O3). Ozone is produced naturally in the stratosphere when highly energetic solar radiation strikes molecules of oxygen, O2, and cause the two oxygen atoms to split apart in a process called photolysis(free oxygen). If a freed atom collides with another O2, it joins up, forming ozone O3 The ozone layer is a deep layer in the stratosphere, encircling the Earth, that has large amounts of ozone in it. The layer shields the entire Earth from much of the harmful ultraviolet radiation that comes from the sun.
What is "carbon capture
Carbon Capture and Storage (CCS) is a technology that can capture up to 90% of the carbon dioxide (CO2) emissions produced from the use of fossil fuels in electricity generation and industrial processes, preventing the carbon dioxide from entering the atmosphere The CCS chain consists of three parts; capturing the carbon dioxide, transporting the carbon dioxide, and securely storing the carbon dioxide emissions, underground in depleted oil and gas fields or deep saline aquifer formations.
The role of coal burning in air pollution
Coal plants are the United States' leading source of SO2 pollution, which takes a major toll on public health, including by contributing to the formation of small acidic particulates that can penetrate into human lungs and be absorbed by the bloodstream. SO2 also causes acid rain, which damages crops, forests, and soils, and acidifies lakes and streams
E-waste issues
E-waste - a growing problem - Electronic gadgets No proper way to dispose Contain valuable metals that can be recovered Often sent to developing Asian nations Problems with lead, mercury, PBDEs, along with the copper, gold and silver worth recycling Exposure to workers 20 States in U.S. have now passed laws regulating E-waste
Eutrophication and processes involved
Eutrophication is the process by which a body of waterdevelops a high concentration of nutrients, such as nitrogen and phosphorus.The nutrients increase the growth of aquatic plants in gen-eral, as well as production of photosynthetic blue-green bacteria and algae. Algae may form surface mats that shadethe water and block light to algae below the surface, greatly reducing photosynthesis. The bacteria and algae die, andas they decompose, BOD increases, reducing the water'soxygen content, sometimes to the point where other organ-isms, such as fish, will die.
19 Definitions and major issues of ground and surface water contamination
Groundwater Pollution Sources of contaminants: Leaks from waste disposal sites and buried tanks and pipes; Seepage from agricultural, industrial (including mining) and household activities; Saltwater intrusion into coastal aquifers (Groundwater contamination is mostly a human health issue) Surface Water Pollution Water Pollutants are emitted from Point Sources Distinct, confined sources Nonpoint Sources Diffused and intermittent (Surface water contamination leads to impaired use, and both wildlife and human health issues)
¥ Ground water issues, contamination, salt intrusion, water reuse
Groundwater pollution differs in several ways fromsurface-water pollution. Groundwater often lacks oxygen,a situation that kills aerobic types of microorganisms(which require oxygen-rich environments) but may pro- vide a happy home for anaerobic varieties (which live in Groundwater Pollution oxygen-deficient environments) Two major problems with the groundwaterin Nassau County are intrusion of saltwater and shal-low-aquifer contamination. Saltwater intrusion, where subsurface salty water migrates to wells being pumped,is a problem in many coastal areas of the world. The most serious groundwater problem on Long Island is shallow-aquifer pollution associated with urban-ization. Sources of pollution in Nassau County includeurban runoff, household sewage from cesspools and septictanks, salt used to de-ice highways, and industrial andsolid waste. These pollutants enter surface waters andthen migrate downward, especially in areas of intensivepumping and declining groundwater levels
Global security and the environment
In many countriestoday, the gap between the rich and the poor is even widerthan it was in the early 1990s. As a result, political, social,and economic security remains threatened, and seriousenvironmental damage from overpopulation and resourceexploitation continues. Environmental protection con-tinues to be inadequately funded. Worldwatch Institutereported in 2002 that the United Nations' annual budgetfor the environment is about $100 million, while the gov-ernments of the world are spending $2 billion per day formilitary purposes. achieving sustainability in the world today hasstrong political and economic components, but it alsohas an environmental component. Terrorism comes inpart from poverty, overcrowding, disease, and conflicts
Ways to minimize water loss
In semiarid regions, replace lawns with decorative gravels and native plants Use more efficient bathroom fixtures Fix all leaks quickly Use dishwashers and washing machines that use less water Sweep sidewalks and driveways instead of hosing them down Wash cars at a car wash, where water may be reused Consider using gray water for appropriate uses Water lawns and plants in the early morning, late afternoon, or at night Use drip irrigation and mulch garden plants Plant drought-resistant vegetation
Relationship between atmospheric inversions, local topography/setting and air pollution
In the lower atmosphere, restricted circulation associated with inversion layers may lead to pollution event Atmospheric inversion; Occurs when warmer air is found above cooler air Concentration of pollutants in the air is directly proportional to the first two factors As either emission rate or downwind travel distance increases, so will the concentration of pollutants City air pollution decreases with increases in third and fourth factors The stronger the wind and the higher the mixing layer, the lower the pollution
Disposal option pros and cons - incineration, land fills, land application of biosolids
Incineration: potential for cogeneration a plus, but can release toxic chemicals if not highly efficient Biosolids - recycling human waste Land applicant of treated sewage sludge for agriculture Issues - pathogens, and persistent inorganic and organic contaminants
Concepts of industrial ecology and zero waste approaches
Issues Taxes, subsidies, all must change Producers responsible for the environmental fate of their product Population mindset change
Structural requirements of sanitary landfills
Landfills may not be sited on floodplains, wetlands,earthquake zones, unstable land, or near airports (birdsdrawn to landfill sites are a hazard to aircraft). Landfills must have liners. Landfills must have a leachate collection system. Landfill operators must monitor groundwater for many specified toxic chemicals. Landfill operators must meet financial assurance criteria to ensure that monitoring continues for 30 years afterthe landfill is closed.
¥ Examples of waterborne diseases
Milwaukee, WI Cryptosporidium Contaminated drinking water 1993 400,000 sick, 100 died, suspect - manure or sewage Wake up call, parasite resistant to chlorination, present in 65-97% of surface waters Walkerton, ON E. Coli Cow manure washed into system Water wells contaminated 500 sick, 5 died Boiling water kills the bacteria
Pros and cons of recycling
Money for recycled goods In down turned economy Goods worth less, some even have to pay to get goods recycled, demand from China decreased Piling up Some cities cutting parts or recycling programs
Link between global warming and ozone depletion- there is none
Ozone depleted due to reactions involving CFCs . CFCs are stable and have a long residence time in the atmosphere. In stratosphere, CFCs release chlorine and enter into catalytic chain reaction- depletes ozone The ozone hole, however, is not the mechanism of global warming. Ultraviolet radiation represents less than one percent of the energy from the sun—not enough to be the cause of the excess heat from human activities. Global warming is caused primarily from putting too much carbon into the atmosphere when coal, gas, and oil are burned to generate electricity or to run our cars. The ozone hole and global warming are not the same thing, and neither is the main cause of the other
CFCs (chlorofluorocarbons)- what are they, how do they get into the atmosphere, what role do they play in ozone destruction
Potent greenhouse gases, Molecules with chlorine, fluorine and carbon- CF2Cl2, CFCl3 Formerly used as propellants in spray cans and currently as refrigerants in air conditioning systems CFC released from various source rise up in the atmosphere and there break down ozone molecules in the earth's upper atmosphere. This reduces the ability of the atmosphere to prevent too much of ultraviolet rays reaching the earth's surface. This in turn harms the animal and plant life on the earth. deposition and reaction. A common example of deposition is 'rain out': compounds that are soluble in water can be removed from the atmosphere by precipitation. This phenomenon is responsible for acid rain
Link between agriculture and water usage
Price water to encourage conservation Use lined or covered canals to reduce seepage Computer monitoring and scheduled release Irrigate when less water is lost to evaporation Use improved irrigation systems Improve soil for easier water penetration Integrate surface water and groundwater use Develop crops requiring less water
Types of waste water treatment (primary, secondary, tertiary). Goals of each
Primary Treatment Incoming raw sewage enters the plant from the municipalsewer line and first passes through a series of screens toremove large floating organic material. The sewage nextenters the "grit chamber," where sand, small stones, andgrit are removed and disposed of. From there, it goes tothe primary sedimentation tank, where particulate mat-ter settles out to form sludge. Sometimes, chemicals areused to help the settling process. The sludge is removedand transported to the "digester" for further processing.Primary treatment removes approximately 30 to 40% of BOD by volume from the wastewater, mainly in the formof suspended solids and organic matter. Secondary Treatment There are several methods of secondary treatment. Themost common treatment is known as activated sludge ,because it uses living organisms—mostly bacteria. In thisprocedure, the wastewater from the primary sedimenta-tion tank enters the aeration tank (Figure 19.16), whereit is mixed with air (pumped in) and with some of thesludge from the final sedimentation tank. The sludgecontains aerobic bacteria that consume organic material(BOD) in the waste. The wastewater then enters the final sedimentation tank, where sludge settles out
Problems associated with overdrafting
Problem of overdraft - taking more groundwater than is naturally replaced A huge problem in some areas Long Island issues: Due to water recharge basins and septic systems, Suffolk County is in water balance - 208 study
Understand why particulates are a serious air pollution problem and the relationship between size and toxicity
Recent studies estimate that 15% to 25% of human mortality in cities is associated with PM Linked to both lung cancer and bronchitis Especially hazardous to elderly and those with asthma Dust can be deposited on plants Interferes with absorption of CO2 and O2 and transpiration global dimming (block sunlight) cools temperature but lessens global warming
The Montreal Protocol- its basic provisions, predictions for future ozone depletion with the treaty in place
Recognition of the role of CFCs in ozone depletion Phase out production of CFCs Collection and Reuse of CFCs Develop substitutes for CFCs HFCs and HCFCs Short-Term Adaptation to Ozone Depletion UN-sponsored effort, as with Kyoto 119 nations (developed and developing) ratified COP-18 in New Delhi; topic was use of methyl bromide (soil fumigant) Phased out production of CFCs by 1995 Atmospheric CFC concentrations are decreasing; should reach pre-1980 levels by 2050 BUT Ozone depletion will persist for some time
13 Renewable harvest - maximum sustainable yield
Relies on the inherent nature of fish populations to replenish themselves based on their "surplus production" - the natural ability for a population to compensate for increased mortality Therefore, fisheries can maximize production by keeping the population at an intermediate level (1/2 of carrying capacity). Carrying Capacity : An abundance at which a population can sustain itself ( Births =Deaths, Constant population)
Sources of air pollution; stationary and mobile sources; point/non-point sources
Stationary sources—those that have a relatively fixed location: -Point sources - Emit pollutants from controllable sites -Fugitive sources Generate air pollutants from open areas exposed to wind processes -Area sources Well-defined areas within which are several sources of air pollutants Mobile sources—move from place to place while emitting pollutants Automobiles, trucks and buses Aircraft, Ships, Trains Nonpoint source pollution generally results from land runoff, precipitation, atmospheric deposition, drainage, seepage or hydrologic modification
BOD
The amount of oxygen required for biochemical decomposition processes is called the biological or biochemical oxygen demand (BOD) It measures the amount of oxygen consumed by microor-ganisms as they break down organic matter within small water samples, which are analyzed in a laboratory. Dead organic matter—which produces BOD—entersstreams and rivers from natural sources (such as deadleaves from a forest) as well as from agricultural runoff and urban sewage When BOD is high, as suggested earlier, the dissolved oxygen content of the water may become too low to sup-port life in the water.
Important air pollutants- definitions of primary and secondary pollutants
ground-level ozone, carbon monoxide, sulfur oxides, nitrogen oxides, and lead Primary pollutants Emitted directly into the air Sulfur dioxide: (coal power plants, industrial) Nitrogen oxides: (contribute acid rain) Carbon monoxide:(binds to hemoglobin in blood, toxic) Ozone: (secondary, kills leaf tissue, beneficial in upper atmosphere) Particulates: Much particulate matter easily visible as smoke, soot or dust, Includes airborne asbestos and heavy metals lead: is constituent of auto batteries and was once added to gasoline. Spread widely around world in soils and water along roadways, Once in soil can enter the food chain Secondary pollutants Produced through reactions between primary pollutants and normal atmospheric compounds
Importance of landfill leachate
The most significant hazard from a sanitary landfill ispollution of groundwater or surface water. If waste bur-ied in a landfill comes into contact with water percolating down from the surface or with groundwater moving later-ally through the refuse, leachate —noxious, mineralizedliquid capable of transporting bacterial pollutants in older landfills and those with no membrane between the waste and the underlying geology, leachate is free to leave the waste and flow directly into the groundwater. In such cases, high concentrations of leachate are often found in nearby springs and flushes
What is pollutant ozone? How does it form? Where does it occur?
Troposheric, or ground level ozone is created by chemical reactions. The majority of tropospheric ozone formation occurs when nitrogen oxides (NOx), carbon monoxide (CO) and volatile organic compounds (VOCs), react in the atmosphere in the presence of sunlight. NOx, CO, and VOCs are called ozone precursors. Motor vehicle exhaust, industrial emissions, and chemical solvents are the major sources of these chemicals. Another source is windshield washer fluid. Ozone occurs in two layers of the atmosphere. The layer closest to the Earth's surface is the troposphere. Here, ground-level or "bad" ozone is an air pollutant that is harmful to breathe and it damages crops, trees and other vegetation. It is a main ingredient of urban smog. The troposphere generally extends to a level about 10 miles up, where it meets the second layer, the stratosphere.
Types of contamination - pathogens, nutrients, excess organic matter, metals, acids, particulates, radioactivity, hot water, organic chemicals
Two important nutrients that cause water-pollutionproblems are phosphorus and nitrogen, and both arereleased from sources related to land use. Stream waterson forested land have the lowest concentrations of phosphorus and nitrogen because forest vegetation ef-ficiently removes phosphorus and nitrogen.
CH18 Where usable water is found on earth
Two main sources of usable water: groundwater and surface water Groundwater: Upper surface of the groundwater is the water table An aquifer is an underground layer of rock, sand, or gravel containing usable significant amounts of groundwater part of the same resource
What is geoengineering? What are some examples? How could they be used to counteract global warming
is the deliberate and large-scale intervention in the Earth's climatic system with the aim of limiting adverse climate change.[2][3][4] Climate engineering is an umbrella term for two types of measures: carbon dioxide removal and solar radiation management. Carbon dioxide removal addresses the cause of climate change by removing one of the greenhouse gases (carbon dioxide) from the atmosphere. Solar radiation management attempts to offset effects of greenhouse gases by causing the Earth to absorb less solar radiation.
Acid rain - sources, - formation - effects - sensitive ecosystems
When acid rain falls, the acidic rainwater dissolves the nutrients and helpful minerals from the soil. These minerals are then washed away before trees and other plants can use them to grow. Not only does acid rain strip away the nutrients from the plants, they help release toxic substance such as aluminum into the soil. most lakes and streams have a pH level between six and eight. Some lakes are naturally acidic even without the effects of acid rain Acid rain does not only damage the natural ecosystems, but also man-made materials and structures. Marble, limestone, and sandstone can easily be dissolved by acid rain. Metals, paints, textiles, and ceramic can effortlessly be corroded. Acid rain can downgrade leather and rubber.
Global environmental treaties
an international treaty was established designating Antarctica a "scientific sanctuary." Thirty years later, in 1991, a major environmental agreement,the Protocol of Madrid, was reached, protecting Antarc-tica, including islands and seas south of 60° latitude. Thecontinent was designated "nuclear-free," and access to itsresources was restricted agreements to reduce air pollutants that destroy strato-spheric ozone (the Montreal Protocol of 1987