Energy Resources: Swamps, Oil, Nuclear, Renewable, and Agricultural Resources - Prof. Arth, Exams of Geography

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Types:

non-renewable or exhaustible: a resource which exists in a fixed amount in various places in the Earth's crust.

energy resources: coal, oil, natural gas, nuclear

**may not be completely exhausted, but economically depleted, cost of extracting is greater than the monetary profit

** Some of these can have their supplies extended by Reusing and/or Recycling

** depletion time:the time it takes to use a certain fraction, usually 80%, of the known or estimated supply of a non-renewable resource


perpetual: a resource that is essentially inexhaustible on a human time scale
energy resources: solar energy, wind, hydropower, geothermal


renewable or potentially renewable: a resource which can be replenished fairly rapidly through natural processes on a human time scale (hours or years or decades)

energy resources: Biomass (trees, other plants, animals)


approximately 5% of world consumes 25% of world’s energy


Non-Renewable Energy Resources:

Fossil Fuels:

coal: solid combustible mixture of organic compounds, with water, sulfur andnitrogen compounds. It forms from the remains of plants subjected to heat & pressure over millions of years. (swamps)

* 30-98% carbon by weight

Who controls it (where is it)?  most abundant fossil fuel (~ 1 quadrillion metric tons)  U.S., Russia, China, & India have 66% of proven reserves & ~ 85% of estimated undiscovered reserves (in swamps)  U.S. alone has about 24% of global reserves  provides ~ 21% of world's commercial energy, 65% of world's electricity, & to make 75% of world's steel

How long will it last?  at current usage rate, identified reserves will last 225 years  if usages rate increases 2% per year 65 years  add in unidentified reserves at current rate 900 years  at increased rate (2%/year) 149 years Advantages Disadvantages


Natural gas: underground deposits of gases consisting of 50-90% by weightmethane gas & small amounts of heavier gaseous hydrocarbon compounds such as propane & butane.

Who controls it(where is it)?  Russia & Kazakhstan have ~ 42% of world's reserves  other countries, Iran, Qatar, Saudi Arabia, Algeria, Nigeria, & Venezuela about 34%  US has about 3% of world’s resources  world reserves estimated at about 140 trillion cubic meters

How long will it last?  at current usage rate, known reserves 200 years  if rate increases 2%/year 80 years  add in undiscovered reserves up to 325 years Advantages Disadvantages
Ample supplies

High net energy yield, low cost (with subsidies)
Less air pollution and lower CO2 emissions that other fossil fuels, moderate environmental impact, low land use, good for fuel cells and gas turbines Releases CO2 when burned Difficult to transfer across oceans, Methane (greenhouse gas) can leak out, Often burned and wasted at wells because of low price, Needs pipeline distribution system


Nuclear energy: energy released when atomic nuclei undergo a nuclear reaction such as the spontaneous emission of radioactivity, nuclear fission or nuclear fusion  436 commercial reactors in 32 countries produce 6% of world's commercial energy & 16% of electricity  usage has leveled-off and is expected to decline in the future do to high costs, stricter government regulations, concerns over safety & waste disposal
Advantages
Disadvantages
Large fuel supply,
Low environmental impact (without accidents),
Moderate land distribution or water pollution,

Moderate land use
High cost (even with subsidies),
Low net energy yield,
Vulnerable to terrorist attacks,
Solutions for long-term storage of radioactive wastes and facilities

Spreads nuclear technology and knowledge to make weapons


Renewable Energy Resources:

solar: direct radiant energy from the sun

*Advantages for use in heating a home: energy is free, Net energy is moderate to high, relatively quick instillation, No CO2 emissions, Very low air and water pollution, Very low land usage, Moderate costs

*Disadvantages for use in heating a home: Need access to sun 60% of time, blockage of sun by other structures, Need heat storage system, high cost(active system), Active collectors unattractive

Passive: using sunlight to control heat, with help of things like windows and roofs
Active: using sunlight to heat water to power pumps that create heat

*Advantages for use in generating electricity: Moderate to high net energy, Low to moderate environmental impact, No CO2 emissions, Relatively quick installation, Reduces dependence on fossil fuels

*Disadvantages for use in generating electricity: Need access to sun, low efficiency, Need storage system or backup, High land use, high costs, DC current must be converted to AC


hydropower: electrical power produced by falling or flowing water  supplies about 6% of world's commercial energy, 4% in U.S.  supplies 20% of world's electricity, 10% in U.S., 99% in Norway

*Advantages: Moderate to high net energy, High efficiency, Low-cost electricity, Long life span, Low CO2 emissions, Provides water for other uses (recreation, irrigation, flood control) Agricultural Resources 03/19/2012
Soil: the main agricultural resource, since without soil there are few plants and thus little agriculture

*A complex mixture of inorganic minerals, decaying organic matter, water, air, and living organisms

*it varies widely in texture, structure, fertility, acidity, and amount

*the problem isn't that there is not enough soil, but not enough in the right places that is good enough for agriculture (arable) AND that too much of what is arable is being lost or degraded


Soil Erosion:

* the movement of soil components by wind and water, often increased by human activities which reduce vegetation cover

* leads to loss of soil fertility & increased sediment in lakes, rivers and other water systems

* some estimate that topsoil is eroding faster than it forms on ~38% of the world’s crop land

* nearly 40% of the world's arable land is seriously degraded by erosion, salinization, and water logging; and food production has been reduced on 16% of world's arable land

* in the U.S. about 1/3 of the original topsoil has been lost by erosion; although the rate of loss has slowed in recent years because of conservation efforts


Desertification: the conservation of marginal lands to desert-like conditions with a drop of 10% or more in productivity

* caused by overgrazing, soil erosion, prolonged drought

* most severe in areas near the world's major deserts which are over used by the local peoples
EX: Sahel in Africa


* Salinization: process by which soil accumulates too much salt to be productive because of toxicity

* stunts crop growth, lowers crop yields, kills plants and makes the soil unusable

* most severe on irrigated lands in drier climates; 21% of world's irrigated cropland has reduced yields from salinization, with a another 30% threatened

* over watering or waterlogging the soil can also lead to reduced productivity and lowered fertility because of salinization


* Soil Fertility:

* plants eventually use-up the nutrients in the soil and if not replenished by decaying plants, then it must be done another way; Usually with organic or inorganic fertilizers


* Solutions to Soil Problems:

* keeping soil covered with vegetation as much as possible so it is not left bare to be washed or blown away

* various methods: conservation tillage, terracing, contour farming, strip cropping, agroforestry, windbreaks, reclamation of lost lands/soil

* to reduce desertification: do not over use marginal lands

* to reduce salinization: reduce irrigation or use desalinated water


** Secondary Agricultural Resource(s) is the products produced, the crops and animals and/or their by products

* Croplands provide 76% of the world’s food

* wheat, rice & corn supply over 1/2 the calories people consume, with 2/3 of the population surviving on these grains alone. The remainder indirectly consume these grains by eating meat products from the livestock which have eaten the grain.

* Rangelands (grazing land for livestock) supply about 17% of the world’s food

 Malnourished (have deficiency of proteins and key nutrients)

* on the other side, 1 out of 7 people in developed countries (1 out of 5 in the U.S.) suffer from overnutrition

* by most estimates, the world produces enough food to meet the basic needs, BUT it is not distributed equally

Solutions

* increase crop yields/acre by better strains of plants, perhaps GMOs, or technology as an outgrowth of “Green Revolutions”

* better distribution systems/methods to get food to the people who need it; more stable political and/or economic situations

* increase development of "newer" foodstuffs, varieties not in large- scale production or commonly consumed

* develop more marginal lands with irrigation and conservation farming methods

* reduce loss of arable land due to soil erosion, salinization & desertification
* develop better methods of agriculture Atmospheric Resources 03/19/2012
COMPOSITION OF THE ATMOSPHERE

* a mixture of discrete gases with solid and liquid particles suspended in it

* Some components are fairly stable while others vary spatially and temporally

** constant Gases (found in same proportions within lower atmosphere)

Constant Gases: 3 gases make-up just under 100% of the atmosphere (First 50 miles)  Nitrogen (N) ~ 78%  Oxygen (O2) ~ 21%  Argon (Ar) ~.9%

** variable Gases (present in differing amounts spatially and/or temporally)

Variable Gases: 3 which influence weather and life systems  Carbon Dioxide (CO2)  Water vapor (H2O)  Ozone (O3)  Methane (CH4)

** Carbon dioxide: absorbs radiant energy emitted by earth (traps in heat)

** water vapor: quite variable throughout atmosphere (affects humidity)  4% by volume in tropics to < 1% in deserts  source of clouds and precipitation  absorbs radiant energy & important in energy transfer  Water is only substance found in all 3 states (solid, liquid, gas)
** Ozone:  concentrated in the stratosphere (10-50 km above surface)  absorbs damaging ultraviolet (UV) radiation  formation is by splitting an O2 molecule with shortwave radiation and the single O atoms combining with an O2  OZONE "HOLE" (Thinning)  Thought to be caused by increasing amounts of chlorofluorocarbons, CFC’s, in the atmosphere  CFC's are a family of chemicals used as coolants (Freon), propellants in aerosol cans, cleaners for computer chips, sterilants, fumigants, bubbles in foam insulation & packaging  UV radiation breaks apart the CFC molecules and the chlorine atom then reacts with an O3 molecule breaking it apart (the chlorine atom takes away one of the oxygen atoms, then the new O2 cannot block out UV radiation)  ozone layer thinning is primarily around the Antarctic & Arctic areas (because the chlorine builds up over winter then it’s always light out for an entire season and thus more vigorously breaks apart ozone )  ozone layer may be reduced by at much as 50% around the Antarctic and 11-38% around the Arctic area  1% loss of O3 leads to a 2% increase in UV radiation at the earth’s surface
** Consequences (of less ozone):
Stratosphere: T° stays constant or increases with altitude (because sunlight is absorbed by ozone);  contains the ozone layer(ozonosphere); very little H2O

Heterosphere: (Humans don’t have much affect on)

Mesosphere: T° decreases with increasing altitude; between ~ 50 & 80 km (31 & 50 mi)

Thermosphere: T° increases dramatically with altitude; T°'s may reach upwards of 900°C (1650°F); area above 80 km (50 mi)


CLIMATE CHANGE: EVIDENCE & TIMING

** Variations in climate on many different time scales from decades to millions of years, & the possible causes of such variations

* climate system; the interaction of the atmosphere, lithosphere, biosphere, & hydrosphere

* when change occurs in one sphere, it affects the other spheres

Evidence of Climate Change  Seafloor sediments ,  Oxygen isotope analysis ,  Tree rings ,  Palynology ,  Geology ,  Historical Records

CLIMATE CHANGE: CAUSES
Non-human Induced Causes:  Plate Tectonics ,  Volcanic output ,  Solar variation,  Astronomical Theory : 3 factors which can lead to climate change (ex: ice age)  Eccentricity : changing shape of Earth’s orbit around the sun o Gets cooler if further from sun or warmer if closer to sun o 100,000 years  Obliquity : changing the tilt of the Earth’s axis o 41,000 years  Precession : Earth wobbling on its axis o 26,000 years

Changes in ability of oceans to store CO2, & heat
Changes in ocean currents:
Changes in average sea level:
Changes in levels of photosynthesis activity:
Changes in storage of carbon in soils:
Changes in cloud cover:


Human Induced Causes:

Changes in atmospheric CO2 levels: a "greenhouse gas" which traps outgoing LW & thus helps keep the earth warm  if levels increase, can lead to global warming  since 1800 have seen a 25% increase on CO2 levels from burning of fossil fuels  a .5°C T° increase has been detected since 1880, but not sure the only cause is increased CO2 levels

Changes in atmospheric levels of other greenhouse gases
* may also contribute to increased T°'s


What is Global Warming?

* the atmosphere is heated by a process known as the greenhouse effect


* alter structure and location of world’s biomes

* uncertainties: positive & negative feedback mechanisms

* increased T° may lead to increased ice melt, which leads to > water vapor amounts in atmosphere, which leads to increased cloud cover, which leads to decreased solar radiation, which can lead to decreased T°


Solutions to Global Warming:

* waste less energy by improving efficiency

* use less coal and oil

* rely more on cleaner energy sources: wind, natural gas, solar, etc.


Possible economic advantages to following the above:  Boost global economy  Provide jobs  Cost less than trying to deal with the effects of not changing


Options:

* do nothing: some believe it is not a threat, or even a hoax

* do more research before acting

* act now to reduce the risks: a type of precautionary strategy, before it gets any worst, or we(humans) are beyond some type of "point of no return"

* act now as part of a no-regrets strategy: even if global warming isn't as bad as some believe, there are other advantages to 'cleaning-up' the atmosphere


AIR POLLUTION

** pollution: the introduction of harmful substances or products into the environment; to contaminate at a rate faster than the environment can ‘cleanup’ in a timely manner

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


SOURCES:

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

Human created: combustion, chemical & nuclear processes, refining processes, mining, farming
* different chemicals & greater amounts have been created by humans


CATEGORIES:

Primary : those pollutants emitted directly from an identifiable source

EX: * CO (carbon monoxide), SO's (sulfur oxides), NO's (nitric oxides),
Particulate matter, volatile organic compounds

Secondary pollutants : produced in atmosphere through reactions among primary pollutants

EX: sulfuric acid, Ozone, Smog