ISB 202 1nd EditionExam # 4 Study Guide Lectures: 23-25Lecture 23 (April 17)Water Pollution- Increase in population- Increase in standard of living- Increase in pollution (water)Freshwater Shortages- U.N. estimates one out of five people lack access to safe drinking water.o 2.6 billion lack acceptable sanitation.- At least 45 countries, mostly in Africa and the Middle East, are considered to have serious water stress.- Water shortages could lead to wars as population grows and climate change dries up some areas. An underlying cause of the Darfur genocide is water scarcity.Major Water Compartments- Oceans -97% of all liquid water in the world.- Contain 90% of world’s living biomass- Moderate earth’s temperature- Gulf Stream carries 100X more water than all rivers on earth.- Average residence time of water in the ocean is about 3,000 years- Glaciers, Ice, and Snowo 2.4%-3% of world’s water is classified as fresh. 90% in glaciers, ice caps, and snowfields.- Groundwatero Second largest reservoir of fresh water Infiltration - process of water percolating through the soil and into fractures and permeable rocks- Zone of aeration - upper soil layers that hold both air and water- Zone of saturation - lower soil layers where all spaces are filled with watero Water table - top of zone of saturationGroundwater- Aquifers - porous layers of sand, gravel, or rock lying below the water tableo Artesian - Pressurized aquifer intersects the surface (water flows without pumping).- Groundwater- Recharge zones - area where water infiltrates into an aquifer Presently, groundwater is being removed faster than it can be replenishedWorldwide Water Use- Water use is divided into agriculture, domestic use and industrial use.- Agriculture ~ 70%- Domestic and industry water use ~ 30%- Water PollutionQualitative water problemo Pollutant: Any material causing deleterious ecological effects or health problems- Water Pollution effects- Aesthetics- Biologicalo Die offso Biomagnification- Public healtho Toxicity- Local effectso Contaminated wells, rivers, lakes, etc.o http://www.bbc.co.uk/news/world-asia-china-23961854- Ecological effectso EutrophicationWater Pollution Sources- Point Sourceo Source of contamination originates from a specific point or areao Example: Effluent Pipes Some Parameters used to Assess Water Quality- DO or dissolved oxygen- Turbidity – the amount of sediment carried in the water- BOD – biological oxygen demand – gives a measure of how much oxygen is needed in the water body – indicates the rate of decomposition and oxygen use in the water- Some Parameters used to Assess Water Quality (cont’d)- Nutrient load – Nitrogen, Phosphates, Potassium, and others- Allochthonous inputs – materials added to the water body from outside the water body, such as leaves, salmonEutrophication- Natural- Aging process of a lake or stream- Cultural- Speeds up the natural processLecture 25 (April 24)Per Capita Consumption- Richest countries have consumed nearly 80% of all commercial energy despite having only 20% of population. This is changing.o India’s oil consumption has doubled since 1992. China went from self-sufficiency to the world’s second largest oil importer.o Many countries are competing for a limited resource.o Americans use 6.5 billion gal, but produce only 2.5 billion gal. We import the rest, whichis becoming increasingly problematic.Per Capita Energy Use- Each person in a rich country consumes nearly as much oil in a day as the poorest people in the world consume in a year.- Some countries such as Norway, Denmark and Japan have a much higher standard of living than the U.S. but use half as much energy per person.- This suggests that we could keep our standard of living while conserving energy.Age of Electricity- Generator invented in 1831- Electricity produced when pass magnet through a coil of coppero Turbine does this automatically- Uses of Crude Oilo Transportationo Produce Electricityo Manufacture of medicineso Fertilizerso Production of Foodstuffso Plastico Building materialso Paintso ClothAdvantages- New fracking techniques are making new sites more profitable- Domestic natural gas production has gone up 30% since 2000- Wells can produce for up to 50 years- Fosters economic development in small communities- Natural gas is better than coal for the environmento “Transitional Fuel”Environmental Issues- Could contaminate ground and surface water o Backflow chemicals from fracking process may cause contamination- Quantity of water usedo Too much water being taken from local ecosystems- Alternative Energy What alternative forms of energy are there that can turn a turbine- Nuclear Power- Fission- Fuel-uraniumNuclear Disadvantages- Nuclear weapons proliferation- Nuclear plant accidents- Chernobyl, Fukushima- Large Capital inputs – emergency containment systems, containment and storage systemsRadioactive Waste Management- U.S. Department of Energy announced plans to build a high-level waste repository near Yucca Mountain Nevada in 1987.o Radioactive waste would be buriedAdvantages of Nuclear power- Cost similar to Coal- Produces minimal GH gases- High energy output- Reliable power source- Modern Safety methods much more reliable- New mini reactors-Size of a car could power 45,000 homes- Proposed Energy Conservation Policies:o Distributional Surcharges Small fee on utility customers to finance renewable energy R & Do Renewable Portfolio Suppliers must get minimum percentage of power from renewable sources.o Green Pricing Allows utilities to profit from conservation programs and charge premium prices for renewable
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