SCI 1101 Exam 4

Oil: Refining ***

separates hydrocarbons in oil by heating; total output: gasoline (49%), diesel fuel and heating oil (25%), jet fuel (8%)

Carbon Dioxide (PDFs)

CO2 fluxes: note that natural fluxes are balanced and anthropogenic (polluting) fluxes upset balance; oceans are retaining CO2: making oceans acidic and killing marine life; per capita energy use: industrial economies = higher rates of energy use (over time CO2 emitted worldwide spiked)

The Science Behind The Story: How Do Climate Models Work? ***

Models are indispensable for scientists studying climate today- and they are increasingly vital for our society because they help us predict what conditions will confront us in the future. Colorful maps and data-rich graphs and charts that scientists generate from climate models are the end result, but the process begins when they put into the model a long series of mathematical equations. These equations describe how various components of Earth's systems function. Some equations are derived from physical laws such as those on the conservation of mass, energy, and momentum. Others are derived from observational and experimental data on physics, chemistry, and biology, gathered from the field. Converted into computing language, these equations are integrated with info about Earth's landforms, hydrology, vegetation, and atmosphere. Earth's climate system is mind boggling to complex, and modelers will never capture all the factors that influence climate. Yet as computers become more powerful and models more sophisticated, they are incorporating more and more of the factors that affect climate. To handle the complexity, most models consist of sub models, each handling a different component- ocean water, sea ice, glaciers, forests, deserts, troposphere, stratosphere. Years ago when models first coupled atmosphere and ocean components together, they were called "coupled" models. This is standard in today's far more complex general circulation models, or global climate models. For a model to function, all it's building blocks must be given equations to make them behave realistically in space and time. But the virtual models can't be so detailed, so modelers approximate reality by dividing time into periods (time steps) and by dividing the Earth's surface into cells or boxes according to a grid (grid boxes). Each grid box contains land, ocean, or atmosphere, much like a digital photo is made up of discrete pixels of certain colors. The grid boxes are arranged in a 3D layer by latitude and longitude, or in equal-sized polygons. The finer the scale of the grid, the greater resolution the model will have, and the better it will be able to predict results region by region. However, more resolution means more computing power is needed, and climate models already strain the most powerful supercomputing networks. Today's best climate models feature dozens of grid boxes piled up from the bottom of the ocean to the top of the atmosphere, with each grid box measuring a few dozen miles wide, and time measured in periods of just minutes. Once the grid is established, the processes that drive climate are assigned to each grid box, with their own rates parceled out amongst the time steps. The model lets the grid boxes interact through time by means of the flux of materials and energy into and out of each grid box. Once modelers have input all this info, learned from our study of earth and the climate system, they let the model run through time and simulate climate, from the past through the present and into the future. If the computer simulation accurately reconstructs past and present climate, then that enhances confidence that it will predict future climate accurately as well. A number of studies have compared model runs that include only natural processes, model runs that include only human-generated processes, and model runs that combine both. Repeatedly these studies have found that the model runs that incorporate both human and natural processes are the ones that fit real-world climate observations the best. This supports the idea that human activities, as well as natural processes, are influencing our climate. The major human influence on climate is our emission of greenhouse gases, and modelers need to select values to enter for future emissions if they want to predict future climate. Generally they will run their simulations multiple times, each time with a different future emission rate according to a specified scenario. Differences between the results from such scenarios tell us what influence these different emission rates would have.

Economic Impacts (PDF)

grain belt shift: crops (corn, wheat, etc.) grow optimally at temps in the midwest; midwest warms, original temp range shifts northward; American breadbasket becomes Canadian breadbasket (food it top US export)

Potential Hazardous Household Products

inside the home : air freshener, bleach, cleaners, toilet bowl cleaner, etc. home maintenance: caulk, grout, insulation, paint, putty, stain, etc. personal care: antiperspirant, hair spray, makeup, shampoo, soap, etc. landscape/yard: fertilizer, lawn care, swimming pool products, etc. pesticides: animal repellant, fungicide, herbicide, insecticide, etc. pet care: flea and tick control, litter, stain/oder remover, etc. arts and crafts: adhesive, glaze, glue, primer, varnish, etc. auto products: break fluid, de-icer, lubricant, sealant, etc. home office: ink, toner, correction fluid, electronics cleaners, pens, etc.

Oil: Formation (PDF) ***

living organisms are deposited, decompose and get buried, buried very deep and pressure and temperature increase, causes crude oil to form, crude oil moves up, gets stuck in a pocket

Oil: Finding Deposits ***

methods: "looking" underground; search for oil associated rocks and minerals (measure transmission of sound waves through rocks; measure magnetic fields to look for salt deposits)

Altered Precipitation Patterns (PDF)

more droughts and more floods; affects agriculture, regions with rapid population growth

Effects of Climate Change ***

more extreme weather systems, altered precipitation patterns, rising sea levels, more damage from hurricanes, shrinking glaciers, shrinking arctic sea ice, wildlife impacted, economic impacts

Water Usage In The US ***

municipal/public water supply (can vary from: climate differences the mix of domestic, commercial, and industrial uses; household sizes; lot sizes; public uses; income brackets; age and condition of distribution system); domestic/commercial (ex: drinking/cooking; bathing; toilet flushing; washing clothes/dishes; watering lawns/gardens; maintaining swimming pools; washing cars); industrial and mining; agricultural; and thermoelectric power generation

Methane (PDFs) ***

natural gas operations and cows are top two sources of emissions; natural gas production way up and leaks at wells can reach 10%, heat trapping from leaks can outweigh benefits of burning natural gas over coal for smaller CO2 emissions

Fossil Fuels and CO2 ***

natural gas: lowest CO2 oil: 30% more than nat gas coal: 45% more than nat gas

Water Use Calculator ***

number of total times household uses water for: showers (daily) , baths (daily), toilet flushes (daily), running water (min/day), dishes by hand (min/day), dishwasher (loads/week), laundry (loads/week), lawn watering (cycles/week), outside water (min/week), filling pool (min/week)

Natural Greenhouse Gasses ***

water vapor and small droplets (97% of natural greenhouse effect), carbon dioxide (majority of other 3%) ex: carbon dioxide (fossil fuel commission, land use changes), methane (natural gas leaks, livestock, decomposition), nitrous oxide (fertilizers, fossil fuel combustion), holocarbons (coolants, formerly propellants)

Is It Really Warming? (PDF) ***

yes ex: 1930s had colder average atmospheric temp whereas the 2000s introduced a large spike in heat ex: carbon dioxide concentrations have risen nearly one third over the last 55 years ex: 2019 said to be the hottest decade

Strip Mining ***

used when coal is near the surface; safer and less intensive, more machinery and less people in mines

Central Case Study: Rising Seas Threaten South Florida (ch. 18) ***

It happens in Miami at least six times a year. The flooding is most severe in Miami Beach, the celebrated strip of glamorous hotels, clubs, shops, and restaurants that rises from a seven-mile barrier island just offshore from Miami. By 2030, flooding is predicted to strike Miami and Miami Beach about 45 times per year- becoming no longer a curious inconvenience, but an existential threat. These mysterious floods that seem to come out of nowhere are a recent phenomenon, so Miami-area residents are just now coming to realize that their costal metropolis is slowly being swallowed by the ocean. The cause? Rising sea levels driven by global climate change. The worlds oceans rose 20 cm (8 in) in the 20th century as warming temperatures expanded the volume of seawater and caused glaciers and ice sheets to melt, discharging water into the oceans. These processes are accelerating today, and scientists predict that sea level will rise another 26-98 cm (10-39 in) or more in this century as climate change intensifies. In the US, scientists find that the Atlantic Seaboard and the Gulf Coast are especially vulnerable. The hurricane-prone shores of Florida, Louisiana, Texas, and the Carolinas are at risk, as are coastal cities such as Houston and New Orleans. From Cape Cod to Corpus Christi, millions of Americans who live in shoreline communities are beginning to suffer significant expenses, disruption to daily life, and property damage as baches erode, neighborhoods flood, aquifers are fouled, and storms strike with more force. Perhaps nowhere in America is more vulnerable to sea-level rise than Miami and it's surrounding communities in South Florida. Six million people live in this region, and three-quarters of them inhabit low-lying coastal areas that also hold most of the region's wealth and property. Experts calculate that Miami alone has more than $400 billion in assets at risk from sea-level rise- more than any other city in the world. South Florida is highly sensitive to sea-level change because its landscape is exceptionally flat; just 1 meter of sea-level rise would inundate more than a third of the region. A 4 meter (3 ft) rise in sea level would submerge Miami and reduce the region to a handful of small islands. The porous limestone bedrock that underlies South Florida also poses a challenge. Pockmarked with holes like Swiss cheese, this permeable Rick lets water percolate through, like a sieve. This is why Miami's floods seem to come from out of nowhere; during the highest tides of the year, ocean water is forced inland, where it mixes with fresh water underground and is pushed up as a bring mixture through the limestone directly into yards and streets. As a result, Miami and it's neighboring cities cannot simply wall themselves off from a rising ocean, because sea walls won't stop water from seeping up from below. Moreover, as salt water moves inland, it contaminates the fresh drinking water of South Florida's Biscayne Aquifer. Fort Lauderdale and several other communities are already struggling with saltwater incursion. Florida is building desalination plants to convert seawater into drinking water, but desalination is expensive and consumes large amounts of energy. Many of Florida's top state-level politicians have long been in denial about climate change, but today Miami-area leaders and citizens are taking action to safeguard their region's future. Commissioners of Broward, Miami-Dade, Monroe, and Palm Beach counties in 2010 adopted an agreement to work together on strategies to combat climate change and its effects in the region. This agreement, the Southeast Florida Regional Climate Change Compact, is garnering wide recognition as a model for regional cooperation in climate issues. In Miami Beach, Mayor Philip Levine won election to office in 2013 after a campaign ad showed him paddling a kayak through the streets of the South Beach neighborhood, promising to address flooding. "I wasn't swept into office," Levine is fond of saying. "I floated in." Under Levine, the city has raised some roadways 3 ft and businesses are urged to remodel their first floors. The city raised stormwater charges on residents and is spending $400 million installing a system of massive pumps to extract floodwater. Engineers expect these measures to get the city through the next couple of decades, but they recognize that more interventions will be needed later.

Central Case Study: Alberta's Oil Sands And The Keystone XL Pipeline (ch 19) ***

Oil sands (aka tar sands) are layers of sand or clay saturated with a viscous, tarry type of petroleum called bitumen. Huge areas of these wet blackish deposits underlie a thinly populated region of northern Alberta, and the implications of mining them for oil are momentous. To some people the oil sands represent wealth and security, a key to maintaining our fossil fuel based lifestyle far into the future. To others they threaten appealing pollution and a severe disruption of earth's climate. To extract oil from oil sands, companies clear the forest and then strip mine the land, creating open pits 215 m (400 ft) deep. The gooey deposits are mixed with hot water and chemicals to separate the bitumen from the sand, and the bitumen is removed and processed. Wastewater is dumped into toxic tailings lakes that are even larger than the mines. Where oil sands are located more deeply underground, hot water is injected down shafts to liquify, separate, and extract the bitumen in place. Mining for oil sands began in Alberta in 1967, but for many years it was hard to make money extracting these low-quality deposits. Rising oil prices after 2003 turned it into a profitable venture, and dozens of companies rushed in. Canadian oil sands became the source of up to 2.3 million barrels of oil per day, making up most of Canada's petroleum extraction, and each truckload that left a mine carried bitumen containing close to $20,000 in oil. In 2015, a sharp downturn in world oil prices slowed the rush, but most companies continued mining, counting on profits from higher future prices to cover their short term losses. Indeed, there is plenty left for the future, thanks to the oil sands, Canada boasts the world's 3rd largest proven reserves of oil, after Venezuela and Saudi Arabia. Canada looked for buyers south of its border first, and the TransCanada Corporation built the Keystone Pipeline to ship diluted bitumen into the US. This pipeline system began operating in 2010, bringing oil from Alberta nearly 3500 km (2200 mi) to Illinois and Oklahoma. An extension later conveyed the oil to refineries on the Texas coast. TransCanada then proposed the Keystone XL extension, a 1400 km (875 mi) stretch of larger-diameter pipeline that would cut across the Great Plains to shave off distance and add capacity to the existing system. This proposed shortcut leg would also transport oil from the newly productive fields of the Bakken Formation in North Dakota and Montana. The Keystone XL pipeline proposal soon met opposition from people living among the proposed route who were concerned about health, environmental protection, and property rights. In Nov 2015, President Obama decided against approving the Keystone XL pipeline and told the nation that his administration had judged that the pipeline "would not serve the national interest of the United States." The pipeline's importance had been "overinflated", he stayed, and its construction would not contribute meaningfully to the US economy, would not lower gas prices for consumers, and would not enhance America's energy security. Moreover, he noted, approving it on the eve of global climate talks in Paris would undercut US leadership just as America sought to gather nations together to address climate change.

The US Environmental Protection Agency Defines Hazardous As: ***

any material that is ignitable, corrosive, explosive, or toxic to humans, plants or animals

More Extreme Weather Patterns (PDF)

warmer arctic stalls weather patterns; more heatwaves and deep freezes; severity and frequency of events increase (harder/longer disasters)

The Science Behind The Story: What Were The Impacts Of The Gulf Oil Spill? ***

As the spill was taking place, government agencies called upon scientists to help determine how much oil was leaking. Researchers eventually determined the rate reached 62,000 barrels per day. Using underwater imaging, aerial surveys, and shipboard water samples, researchers tracked the movement of oil up through the water column and across the Gulf. These data helped predict when and where oil might reach shore, thereby serving to direct prevention and cleanup efforts. Meanwhile, as engineers struggled to seal off the well using remotely operated submersibles, researchers assisted government agencies in assessing the fate of the oil. These data would help inform studies of the oil's impacts on marine life and human communities. Tracking movement of the oil underwater was challenging. University of Georgia biochemist Mandy Joye, who had studied natural seeps in the Gulf for years, documented that the leaking wellhead was creating a plume of oil the size of Manhattan. She also found evidence of low oxygen concentrations, or hypoxia, because some bacteria consume oil and gas, depleting oxygen from the water and making it inhabitable for fish and other creatures. Joye and other researchers feared that the thinly dispersed oil might prove devastating to plankton and to the tiny larvae of shrimp, fish, and oysters. Scientists taking water samples documented sharp drops in plankton during the spill, but it would take years to learn whether the impact on larvae will diminish populations of adult fish and shellfish. Studies on the condition of living fish in the region show gill damage, tail rot, lesions, and reproductive problems at much higher levels than is typical. What was happening to life on the sea floor was a mystery, because only a handful of submersible vehicles in the world were able to travel to the crushing pressures of the deep sea. Luckily, a team of researchers led by Charles Fisher of Penn State University was scheduled to embark on a regular survey of deep water coral across the Gulf of Mexico in late 2010. Using the three person submersible (Alvin) and the robotic vehicles (Jason and Sentry), the team found healthy coral communities at sites far away from the Macondo well but found dying corals and brittlestars covered in a brown material at a site 11 km from the well. Eager to determine whether this community was contaminated by the BP oil spill, the research team added chemist Helen White is Haverford College and returned a month later, thanks to a National Science Foundation program that funds rapid response research. On this trip, chemical analysis of the brown material showed it to match oil from the BP spill. Other questions revolve around impacts of the chemical dispersant that BP used to break up the oil, a compound called Corexit 9500. Work by biologist Philippe Bodin following the Amoco Cadiz oil spill in France in 1978 had found that corexit 9500 appeared to be more toxic to marine life than the oil itself. BP threw an unprecedented amount of this chemical at the Deepwater Horizon spill, injecting a great deal directly into the path of the oil at the wellhead. This caused oil to dissociate into trillions of tiny droplets that dispersed across large regions many scientists worried that this expanded the oil's reach, affecting more plankton, larvae, and fish. Impacts of the oil on birds, sea turtles, and marine animals were less difficult to assess, and hundreds of these animals were cleared and saved by wildlife rescue teams. Officially confirmed deaths numbered 6104 birds, 605 turtles, and 97 mammals, but a much larger, unknown, number surely succumbed to the oil and were never found. Scientists expect some impacts of the gulf spill to be long lasting. Oil from the similar Ixtoc blowout off Mexico's coast in 1979 still lies in sediments near dead coral reefs, and fishermen there say it took 15-20 years for catches to return to normal. After the Amoco Cadiz spill, it took seven years for oysters and other marine species to recover. In Alaska, oil from the 1989 Exxcon Valdez spill remains embedded in beach and sand today.

Natural Gas: Uses ***

water heating, space heating, vehicles

Acidic Mine Drainage ***

drainage patterns altered; rain interacts with pyrite/pollutants (minerals are rich with sulfur; Sulfur + Water = Sulfuric Acid)

Water Wiser Drip Calculator ***

dripping faucets: number of drips per minute; fast running faucets: time in seconds

The Science Behind The Story: What Can We Learn From The World's Longest Ice Core? ***

The ice sheets of Antarctica and Greenland trap tiny air bubbles, dust particles, and other proxy indicators of past conditions. By drilling boreholes and extracting ice cores, researchers can tap into these priceless archives. Recently, researchers drilled and analyzed the deepest core ever. At a remote and pristine site in Antarctica named Dome C, they drilled 3270 m (10,728 ft) to bedrock and pulled out more than 800,000 years worth of ice. The longest previous ice core had "only" gone back 420,000 years. Ice near the top of these cores was laid down most recently, and ice at the bottom is oldest, so by analyzing ice at intervals along the core's length, researchers can generate a timeline of environmental change. To date layers of the ice core, researchers for analyze deuterium isotopes to determine the rate of ice accumulation, referencing studies and models of how ice compacts over time. They then calibrate the timeline by matching recent events in the chronology (ex: major volcanic eruptions) with independent data sets from previous cores, tree rings, and other sources. Dome C, a high summit of the Antarctic sheet ice, is one of the coldest spots on the planet, with an annual mean temp of -54.5 degrees C (-98.1 F). The Dome C ice core was drilled by the European Project for Ice Coring in Antarctica (EPICA), a consortium of researchers from 10 European nations. In 2004, this team of 56 researchers published a paper in the journal "Nature", reporting data on surface air temp across 740,000 years. The researchers had obtained this temp data by measuring the ratio of deuterium isotopes to normal hydrogen in the ice, a ratio that is temp dependent. From 2005-2008, five follow up papers reported analyses of greenhouse gas concentrations from the EPICA ice core and extended the gas and temp data back to cover all 800,000 years. By analyzing air bubbles trapped in the ice, the researchers quantified atmospheric concentrations of carbon dioxide and methane. These data show that by emitting these greenhouse gases since the industrial revolution, we have brought their atmospheric concentrations well above the highest levels they reached naturally at any time in the past 800,000 years. Today's carbon dioxide spike is too recent to show up in the ice core, but its concentration is far above previous max values shows in the figure. These data reveal that we as a society have brought ourselves deep into uncharted territory. The EPICA results also confirm that temp swings in the past were tightly correlated with concentrations of greenhouse gases. This finding bolsters the scientific consensus that greenhouse gas emissions are causing our planet to warm today. Also clear from the data is that temperature has varied with swings in solar radiation due to Milankovich cycles. The complex interplay of the Milankovich cycles produced periodic temp fluctuations on Earth, resulting in periods of glaciation and in warm interglacial periods. The Dome C ice core spans 8 glacial cycles. The early glacial cycles differ from the recent cycles. In the recent cycles, glacial periods are long, whereas interglacial periods are brief, with rapid rise and fall of temperature. Interglacials thus appear on the graph as tall, thin spikes. In older glacial cycles, the glacial and interglacial periods are of more equal duration, and interglacials are not as warm. The shift in the nature of glacial cycles had been noted before by researchers working with oxygen isotope data from marine fossils. But why cycles should differ before and after the 450,000 year mark, no one knows.

The Science Behind The Story: How Do We Find And Estimate Fossil Fuel Deposits? ***

The industry employs petroleum geologists who study underground rock formations to predict where deposits of oil and natural gas might lie. Because the organic matter that gave rise to fossil fuels was buried in sediments, geologists know to look for sedimentary rock that may act as a source. They also know that oil and gas tend to seep upward through porous rock until being trapped by impermeable layers. To map subsurface rock layers, petroleum geologists first survey the landscape in the ground and from airplanes, studying rocks on the surface. Because rock layers often become tilted over geologic time, these strays may protrude at the surface, giving geologists an informative "side on" view. But to really understand what's deep beneath the surface, scientists conduct seismic surveys. In seismic surveying, a base station creates powerful vibrations at the surface by exploding dynamite, thumping the ground with a large weight, or using an electric vibrating machine. This sends seismic waves down and outward in all directions through the ground, just as ripples spread when a pebble is dropped into a pond As they travel, the waves encounter layers of different types of rock. Each time a seismic wave encounters a new type of rock with a different density, some of the wave's energy is reflected off the boundary. Other wave energy way be refracted (bent) sending refraction waves upward. As reflected and refracted waves return to the surface, devices called seismometers record their strength and timing. Scientists collect data from seismometers at multiple surface locations and run the data through computer programs. By analyzing how long it takes all the waves to reach the various receiving stations, and how strong they are at each site, researchers can triangulate and infer the densities, thicknesses, and locations of underlying geologic layers. Seismic surveying is similar to how we use sonar in water or how bats use echolocation as they fly. It is also used for finding coal deposits, salt and mineral deposits, and geothermal energy hotspots, as well as for studying faults, aquifers, and engineering sites. Using data from such techniques, geologists with the US Geologists Survey (USGS) in 1998 assessed the subsurface geology of the Arctic National Wildlife Refuge in Alaska's North Slope to predict how much oil it may hold. Over three years, dozens of scientists conducted fieldwork and combined their results with a reanalysis of 2300 km (1400 mi) of seismic survey data that industry has collected in the 1980s. After studying their resulting subsurface maps, USGS scientists concluded, with 95% certainty, that between 11.6 and 31.5 billion barrels of oil lay underneath the region of the refuge that Congress has debated opening for drilling. The mean estimate of 20.7 billion barrels is enough to supply the US for 3 years at its current rate of consumption. However, some portion of geologists estimate technically recoverable amounts of fuels. In its estimate for the Arctic Refuge, the USGS calculated technically recoverable oil to total 4.3-11.8 billion barrels, with a mean estimate of 7.7 billion barrels. The portion of this oil that is economically recoverable depends on the costs of extracting it and the price of oil on the world market. USGS scientists calculated that at a price of $40 per barrel, 3.4-10.8 billion barrels would be economically worthwhile to recover. At higher prices, the economically recoverable amount would be closer to the technically recoverable amount.

Permafrost and Methane

arctic warms, permafrost thaws, microbes activate and break down organic matter in soil, decomposition generates methane (endless cycle: the more radiation is trapped in atmosphere the more the ice melts which in turn causes decomposition, thus creating more radiation and heating earth more)

Hubert's Prediction (PDF) ***

bell shaped curve; peaks and then decreases (reality: hit peak and kept rising)

Calculating Ecological Footprint ***

by summing up all the land areas; how much natural capital is there per person? take current global population and divide it by the number of acres of biologically productive land, we find that there are currently 4.7 acres of productive land on the planet per person; therefore, in order to live sustainably, each person on the planet should have an ecological footprint of 4.7 acres or less; while individuals in developing countries often have footprints at or below this level, citizens of highly industrialized countries often exceed it by a sizable amount

Ecological Footprints Are Calculated By Examining Land Used For:

cultivating food crops; grazing livestock; growing timber; harvesting fish and other organisms from oceans; housing, infrastructure, transportation, shopping, energy production; sequestering in trees the carbon dioxide produced by driving, electricity usage, etc.

Global Warming ***

human activities affect system (add CO2 and other "greenhouse gasses" to the atmosphere), raises temps in atmosphere and ocean waters, hotter atmosphere/oceans = hotter climate

Underground Coal Mining ***

people mine by hand; much more dangerous: cave ins (ceiling collapses), gasses (explode, others are toxic- canary in a coal mine), mine flooding (old mines collect groundwater and when opened the mine shafts can cause flooding), fires

Climate Model Predictions: Negative Feedback Loops

phytoplankton: warmer oceans + more CO2 = increase in algae populations; algae absorb CO2, slowly warming

Oil: Extraction ***

primary recovery: pump oil to surface (yields 15% of original reserve) secondary recovery: force out oil with water (yields another 20% (35% total)) advanced recovery: force out oil with steam, CO2, or natural gas (yields another 10% (45% total))

Coal: Origins ***

remains of ancient swamp plants

Oil: Origins ***

remains of plankton

Natural Gas: Origins ***

remains of swamp plants and plankton

Climate Model Predictions: Positive Feedback Loops (PDF)

removing the lid from the top of the planet, loss of reflective ice cooling "albedo", replaced by dark ocean warming; more absorbed heat = warmer oceans = further melting of ice caps

Estimating Oil Reserves ***

secondary and advanced are only used when profitable (costs more to get the oil than to sell it)

The Greenhouse Effect (PDF) ***

shorter wavelength UV and visible light pass through atmosphere; longer wavelength infrared radiation is absorbed and re-emitted by atmosphere, creating greenhouse effect

Wildlife Impacted (PDF)

species' ranges shift northward, often to poorer habitat; some populations disappear entirely; warming, acidifying oceans threaten marine life

Ways To Reduce Water Use Around The Home ***

stop leaks, replace old toilets, replace old clothes washers, plant the right plants, provide only the water plants need

Why Do Climate Model Predictions Vary? (PDF) ***

there are dozens of feedback loops that affect earth's climate; some are negative (slow warming) and some are positive (fast warming); unsure of their relative strengths and interactions because climate is amazingly complex; educated judgement calls in strengths and interactions lead to differing model predictions

Rising Sea Levels (PDF)

thermal expansion (39%), glaciers (27%), Greenland/Antarctic ice sheets (21%), groundwater (13%)

Shrinking Glaciers (PDF)

threatens regions that rely on glaciers for water supply

Ecological Footprint ***

tool that estimates your overall impact in the environment and describes the area of land needed to supply the resources usted and wastes produced by each individual

Coal: Uses (PDF) ***

used primarily in industrialized world for electricity production; how to make electricity: Boiler: coal input, water brought in, heat from coal combustion converts water into steam Turbine: steam input from boiler, steam under pressure presses on blades and turns turbine and shaft Generator: shaft turns magnet and creates current in coils of wire within generator