Notes on Water Resources - Resources, Society and Environment | GEOG 1125, Study notes of Geography

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* WATER (H2O)

* originally formed within the earth & brought to surface by outgassing or degrassing

* collected on surface after earth cooled some 3.8 BYBP (Billion years before present)  Don’t need to know

* covers 71% of earth by area

* constitutes 70% of our bodies


* Distribution

* 97.22% oceans & other saltwater bodies 2.78% is freshwater

* of freshwater: 77% is in ice & glaciers  22% is groundwater  1% is in freshwater lakes & ponds, rivers & streams
** HYDROLOGIC (Water) CYCLE

* evapotranspiration * condensation * precipitation * run-off  Freezing: liquid to solid  Melting: solid to liquid  Evaporation: liquid to gas  Condensation: gas to liquid  Sublimation: solid to gas  Deposition: gas to solid


** Groundwater

* 2nd largest potential source of freshwater (22%)

* accumulates by percolation through the soil into reservoirs or aquifers

* how well it percolates is controlled by:
 porosity: the percentage of rock or soil that is void (pore) space; how much water a rock or material can hold
* eastern U.S. is in better shape than central to western parts because of greater average annual precipitation

What for?

* Primary uses: 70% used for irrigation on 18% of world’s cropland to produce 40% of world’s food

* industry another 20%, with the remaining 10% to cities & residences
* The Eastern US gets more rain than the Western US

* Water Scarcity is caused by one or more of the following 4 factors:
1) Dry climate: not enough precipitation to meet human needs
2) Drought: a period of 21 days or longer with precipitation at least 70% below normal
3) Desiccation: drying of the soil due to deforestation & overgrazing by livestock
4) Water stress: low availability due to increasing population relying on limited supplies

* recent effects of one or more of these factors:
 ~500 million people live in countries with water stress  1.2 billion poor people cannot afford safe drinking water  droughts have killed over 24,000/year since 1970 and created millions of environmental refugees

* potential problems:
 Increasing population creates increasing demand on & waste of regionally limited supplies, and increasing potential for pollution o EX: China, India, Africa, Middle East, South America  Can lead to violent conflicts over water rights, claims, usage, etc. o EX: Middle East: along Nile River; Jordan River Basin; Tigris & Euphrates river systems  Increasing industrialization of developing countries increases usage and pollution
* ways to supply more water:
 build dams & reservoirs: Benefits: controls supply, produced by hydroelectricity, supply water for irrigation, industry, etc., recreational activities and jobs Costs: ecological damage, large building costs, changes down river flow dynamics, sediment build up  water transfers: transfers of water via tunnels, aqueducts, and underground pipes from reservoirs to water-poor areas Benefits: gets water to where it is most needed for rural and/ or urban uses Costs: ecological damage, increased pollution, potential for increased waste due to lower prices
EX: California Water Project, Aral Sea
 withdraw more from groundwater sources: Benefits: can be removed year round, less loss to evaporation, often less expensive to develop Costs: if withdrawn faster than replenished results in lowering of water table, aquifer depletion, aquifer subsidence, saltwater intrusion in coastal areas, reduced stream flow  desalination: removing dissolved salts from ocean water to create “fresh water” 1) distillation: heating salt water until it evaporates and the salts are left behind, then condensing it as fresh water
In agriculture: reduce use of gravity irrigation methods, use center-pivot, low-pressure sprinklers, low-energy precision, application sprinkles, drip irrigation systems, irrigate at night, etc. In urban, domestic, and industrial systems: xeriscaping, fix leaks, upgrade/redesign industrial methods, water saving appliances, toilets, showers, government imposed conservation, raise water rates In both areas: Reduce or remove subsidies which will cause users to pay fair market value and probably instill conservation Polluting of the Environment 04/11/2012
** pollution: the introduction of harmful substances or products into the environment; to contaminate at a rate at which the environment cannot clean it up

Outdoor Air Pollution

** Air Pollutants: airborne particles and gases in concentrations which endanger health of organisms and the environment

Sources:

Non-Human created: volcanoes, sea salt, pollen, fire, dust, bacteria, and viruses

Human created: combustion of fossil fuels, chemical and nuclear processes, refining processes, mining, farming

* different chemicals & greater amounts have been created by humans than by the environment without humans

Categories:

Primary (point source): those pollutants emitted directly from an identifiable source, such as a car tailpipe or factory smokestack

EX:

* CO (carbon monoxide): 2/3 comes from cars, the most abundant primary pollutant

* SO's (sulfur oxides): from coal & oil combustion; can become acid deposition

* NO's (nitric oxides): from power plants & cars; can also become acid deposition

* Particulate matter: solid particles & liquid droplets

* volatile organic compounds: also called hydrocarbons, solid, liquid & gases of H & C; in cities primarily from cars


Secondary pollutants: produced in atmosphere through reactions among primary pollutants

* many triggered by sunlight in photochemical reactions

* sulfuric acid: H2SO4 (SO2 + H2O) one form of acid rain

* Ozone: harmful near the surface and a component of smog
* harms crops and other vegetation
* irritates eyes and lungs

* Smog: in urban and industrial areas; a mixture of different pollutants, some primary and some secondary
* improve fuel efficiency, increase & improve mass transit


Indoor Air Pollution

Types: primarily from man-made chemicals; another is radon gas

* may by 2 to 5 times higher inside a home than outside
* levels may be up to 18 times higher inside a vehicle than outside

Sources: man-made household materials, furniture, building materials, drapes, upholstery, clothing, cleaning products, etc.

Solutions: increase. improve ventilation of air by use of exhaust hoods, changing air more frequently with outside air, circulate air through greenhouses, use less-polluting materials


WATER POLLUTION

Types:

Point-source: the source of the pollution is readily identifiable such as pipingdischarging waste into a river

Non-Point Source: cannot be traced to any single site of discharge; usually a large land area such as agricultural lands or urban areas
may be materials such as: organic wastes, organic chemicals, inorganic chemicals, sediment(dirt), infectious agents, etc.

Sources:

* water-using industries: steel, chemicals, paper production, and food processing are major pollutants

* municipal sewage: wastewater from houses, hotels, businesses, restaurants, etc. Most of it is cleaned, but still some pollution. In LDC's there may be little if any sewer treatment.
 EX: average U.S. urban resident uses ~ 180 gallons of water per day for drinking, cooking & bathing; the average per person for all uses is about 2400 gallons per day

* agriculture: fertilizers, pesticides, and other chemicals put on fields too often end up in nearby lakes and rivers

* non-vegetated land areas: increased sediment runoff and thus load of streams, lakes, etc.; primarily from bare agricultural lands or deforested/cleared lands

Effects:

* making potential drinking water undrinkable, and/or increasing cost of cleaning before clearing

* harm to aquatic life: oxygen depletion (because of decomposition of algae after increased photosynthesis from runoff like nitrogen), increased toxic levels in organisms such as fist, thermal pollution

* passage/creation of diseases such as typhoid, cholera, etc.

Solutions:

* reduce fertilizer, pesticide and other agricultural non-profit runoff by reducing use or by planting vegetation buffer zones

* reduce sediment runoff by reducing soil erosion

* cleanup emissions from point-sources

* upgrade sewage treatment plants

* increase monitoring of and enforcement of current laws, and strengthen current laws


Land Pollution

Sources: * by-products of consumerism; the packaging of all the "stuff" we buy, send, use EX: ~ 4 pounds of solid waste is generated per person per day in the U.S. (60% residential, 40% business)

Types: paper products, plastics, metals, etc.
** most ends up in sanitary landfills

Ways to Reduce Pollution
** REDUCE, REUSE, RECYCLE
** Reduce waste created, use more efficiently, reduce consumption
** Reuse materials before discharging or recycling
** Recycle materials so they may be used to make new products EX: in U.S. recycling of solid waste has increased from 7% of all solid waste in 1970 to 30% in 2000.


Principals which should Guide Decision Making

* Humility principle: recognize and accept that humans have a limited capacity to manage nature because of understanding of nature & the consequences of our actions is quite limited

* Reversibility principle: try not to do something that cannot be reversed later if the decision turns out to be wrong

* Precautionary principle: when evidence indicated an activity raises threat of harm to human heath or the environment, take precautionary measures to prevent or reduce such harm; it is better to be safe than sorry

* Prevention principle: whenever possible, make decisions that help prevent a problem from occurring or becoming worse

* Integrative principle: make decisions that involve integrated solutions to environmental and other problems

* Environmental Justice principle: establish environmental policy so no group of people bears an unfair share of the harmful environmental risks from industrial, municipal, and commercial operations, OR the execution of laws, regulations, and policies


Policy Making in the U.S.
Basic Steps:
1. laws passed by the legislative branch 2. regulations instituted by the executive branch to put laws into effect 3. funding to implement and enforce the laws and regulations (combinations of legislative and executive branch) 4. Often the judicial branch is called upon to determine the validity of a particular law or set of laws

* this is accomplished by the following measures:

* persuade (lobby) lawmakers that an environmental problem exists & the government has a responsibility to address it; This is usually done by one or several NGO's, other special interest groups, or individuals, lobbyists

* special interest groups, and others who oppose a proposed law will likewise lobby lawmakers against passage of a law

* both sides will try to influence how laws are written & to pass laws to deal with the problem

* proposed laws will be evaluated by several committees with the legislative branch, where this lobbying, in part, will take place

* once a law has been passed by the legislative branch, it must be signed into law by the executive branch

* funding to implement & enforce the law must be appropriated

* have the appropriate government department or agency draw up regulations for implementing each law

* implement & enforce the approved laws

* special interest groups, NGO's, businesses, or any affected group or individual may take the agency/government to court for failing to implement & enforce the regulations, OR for enforcing them to rigidly, OR because they want to have the law changed and/or abolished

* this is often referred to as the Policy Life Cycle:
1. Recognition: recognizing that there’s a problem 2. Formulation: looking for solutions 3. Implementation: implement the solutions 4. Control: make sure things are improving and the laws are being followed

What has been the Outcome? * thousands of laws pertaining the how humans should interact with the other components of the environment have been passed  EX: Clean Water Act, Clean Air Act, Endangered Species act * entire new departments and agencies in the US, and elsewhere, have been created to deal with the interactions of humans and the environment (GNOs, citizen groups, etc.)  EX: an estimated 30,000 groups at the international, national, state, and local level (10,000+ in the US alone with over 8 million members)