Fluid and crystallized intelligence

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https://en.wikipedia.org/wiki/Fluid_and_crystallized_intelligence 

The concepts of fluid intelligence (g_f) and crystallized intelligence (g_c) were introduced in 1963 by the psychologist Raymond Cattell. According to Cattell's psychometrically-based theory, general intelligence (g) is subdivided into g_f and g_c. Fluid intelligence is the ability to solve novel reasoning problems and is correlated with a number of important skills such as comprehension, problem-solving, and learning. Crystallized intelligence, on the other hand, involves the ability to deduce secondary relational abstractions by applying previously learned primary relational abstractions.

History

Fluid and crystallized intelligence are constructs originally conceptualized by Raymond Cattell. The concepts of fluid and crystallized intelligence were further developed by Cattell and his former student John L. Horn.

Fluid versus crystallized intelligence

Fluid intelligence (g_f) involved basic processes of reasoning and other mental activities that depend only minimally on prior learning (such as formal and informal education) and acculturation. Horn notes that it is formless and can "flow into" a wide variety of cognitive activities. Tasks measuring fluid reasoning require the ability to solve abstract reasoning problems. Examples of tasks that measure fluid intelligence include figure classifications, figural analyses, number and letter series, matrices, and paired associates.

Crystallized intelligence (g_c) includes learned procedures and knowledge. It reflects the effects of experience and acculturation. Horn notes that crystallized ability is a "precipitate out of experience," resulting from the prior application of fluid ability that has been combined with the intelligence of culture. Examples of tasks that measure crystallized intelligence are vocabulary, general information, abstract word analogies, and the mechanics of language.

Example application of fluid and crystallized abilities to problem-solving

Horn provided the following example of crystallized and fluid approaches to solving a problem. Here is the problem he described:

"There are 100 patients in a hospital. Some (an even number) are one-legged but wearing shoes. One-half of the remainder are barefooted. How many shoes are being worn?"

The crystallized approach to solving the problem would involve the application of high school-level algebra. Algebra is an acculturational product.

${\displaystyle x+1/2\ast (100-x)\ast 2}$ is the number of shoes worn, where x equals the number of one-legged patients. ${\displaystyle 100-x}$ equals the number of two-legged patients. The solution boils down to 100 shoes.

In contrast to the crystallized approach to solving the problem, Horn provided a made-up example of a fluid approach to solving the problem, an approach that does not depend on the learning of high school-level algebra. In his made-up example, Horn described a boy who is too young to attend secondary school but could solve the problem through the application of fluid ability: "He may reason that if half the two-legged people are without shoes, and all the rest (an even number) are one-legged, then the shoes must average one per person, and the answer is 100."

Relationship to Piaget's theory of cognitive development

Researchers have linked the theory of fluid and crystallized abilities to Piaget's theory of cognitive development.  Fluid ability and Piaget's operative intelligence both concern logical thinking and the "eduction of relations" (an expression Cattell used to refer to the inferring of relationships). Crystallized ability and Piaget's treatment of everyday learning reflects the impress of experience. Like fluid ability's relation to crystallized intelligence, Piaget's operativity is considered to be prior to, and ultimately provides the foundation for, everyday learning.

Measurement of fluid intelligence

Various measures have been thought to assess fluid intelligence.

Raven's Progressive Matrices

The Raven's Progressive Matrices (RPM) is one of the most commonly used measures of fluid ability. It is a non-verbal multiple-choice test. Participants have to complete a series of drawings by identifying relevant features based on the spatial organization of an array of objects and choosing one object that matches one or more of the identified features. This task assesses the ability to consider one or more relationships between mental representations or relational reasoning. Propositional analogies and semantic decision tasks are also used to assess relational reasoning.

Woodcock–Johnson Tests of Cognitive Abilities, Third Edition

In the Woodcock–Johnson Tests of Cognitive Abilities, Third Edition (WJ-III), g_f is assessed by two tests: Concept Formation and Analysis Synthesis. Concept Formation tasks require the individual to use categorical thinking; Analysis Synthesis tasks require general sequential reasoning.

Concept Formation

Individuals have to apply concepts by inferring the underlying "rules" for solving visual puzzles that are presented with increasing levels of difficulty. As the level of difficulty increases, individuals have to identify a key difference (or the "rule") for solving puzzles involving one-to-one comparisons. For more difficult items, individuals need to understand the concept of "and" (e.g., a solution must have some of this and some of that) and the concept of "or" (e.g., to be inside a box, the item must be either this or that). The most difficult items require fluid transformations and cognitive shifting between the various types of concept puzzles that the examinee had worked with previously.

Analysis–Synthesis

In the Analysis–Synthesis test, the individual has to learn and orally state the solutions to incomplete logic puzzles that mimic a miniature mathematics system. The test also contains some of the features involved in using symbolic formulations in other fields such as chemistry and logic. The individual has presented a set of logic rules, a "key" that is used to solve the puzzles. The individual has to determine the missing colors within each of the puzzles using the key. Complex items presented puzzles that require two or more sequential mental manipulations of the key to deriving a final solution. Increasingly difficult items involve a mix of puzzles that requires fluid shifts in deduction, logic, and inference.

Wechsler Intelligence Scales for Children, Fourth Edition

The Wechsler Intelligence Scales for Children, Fourth Edition (WISC-IV) is used to have an overall measure in cognitive ability with five primary indexing scores. In the WISC-IV, the Perceptual Reasoning Index contains two subtests that assess g_f: Matrix Reasoning, which involves induction and deduction, and Picture Concepts, which involves induction.

Picture Concepts

In the Picture Concepts task, children have presented with a series of pictures on two or three rows and asked which pictures (one from each row) belong together based on some common characteristic. This task assesses the child's ability to discover the underlying characteristic (e.g., rule, concept, trend, class membership) that governs a set of materials.

Matrix Reasoning

Matrix Reasoning also assesses this ability as well as the ability to start with stated rules, premises, or conditions and to engage in one or more steps to reach a solution to a novel problem (deduction). In the Matrix Reasoning test, children have presented with a series or sequence of pictures with one picture missing. Their task requires the child to choose the picture that fits the series or sequence from an array of five options. Since Matrix Reasoning and Picture Concepts involve the use of visual stimuli and do not require expressive language, they have been considered to be non-verbal tests of g_f.

In the workplace

Within the corporate environment, fluid intelligence is a predictor of a person's capacity to work well in environments characterised by complexity, uncertainty, and ambiguity. The Cognitive Process Profile (CPP) measures a person's fluid intelligence and cognitive processes. It maps these against suitable work environments according to Elliott Jaques's Stratified Systems Theory. Fe et al. (2022) show that fluid intelligence measured in childhood predicts labor market earnings.

Factors related to measuring intelligence

Some authors have suggested that unless an individual is truly interested in a problem presented on an IQ test, the cognitive work required to solve the problem may not be performed owing to a lack of interest. These authors have contended that a low score on tests that are intended to measure fluid intelligence may reflect more of a lack of interest in the tasks than an inability to complete the tasks successfully.

Development across life span

Fluid intelligence peaks at around age 20 and then gradually declines. This decline may be related to local atrophy of the brain in the right cerebellum, a lack of practice, or the result of age-related changes in the brain.

Crystallized intelligence typically increases gradually, stays relatively stable across most of adulthood, and then begins to decline after age 65. The exact peak age of cognitive skills remains elusive.

Fluid intelligence and working memory

Working memory capacity is closely related to fluid intelligence, and has been proposed to account for individual differences in g_f. The linking of working memory and g_f has been suggested that it could help resolve mysteries that have puzzled researchers concerning the two concepts.

Neuroanatomy

According to David Geary, g_f and g_c can be traced to two separate brain systems. Fluid intelligence involves the dorsolateral prefrontal cortex, the anterior cingulate cortex, and other systems related to attention and short-term memory. Crystallized intelligence appears to be a function of brain regions that involve the storage and usage of long-term memories, such as the hippocampus.

Research on training working memory and the training's indirect effect on fluid ability

Because working memory is thought to influence g_f, then training to increase the capacity of working memory could have a positive impact on g_f. Some researchers, however, question whether the results of training interventions to enhance g_f are long-lasting and transferable, especially when these techniques are used by healthy children and adults without cognitive deficiencies. A meta-analytical review published in 2012 concluded that "memory training programs appear to produce short-term, specific training effects that do not generalize."

In a series of four individual experiments involving 70 participants (mean age of 25.6) from the University of Bern community, Jaeggi et al. found that, in comparison to a demographically matched control group, healthy young adults who practiced a demanding working memory task (dual n-back) approximately 25 minutes per day for between 8 and 19 days had significantly greater pre-to-posttest increases in their scores on a matrix test of fluid intelligence. There was no long-term follow-up to assess how enduring the effects of training were.

Two later n-back studies did not support the findings of Jaeggi et al. Although participants' performance on the training task improved, these studies showed no significant improvement in the mental abilities tested, especially fluid intelligence and working memory capacity.

Thus the balance of findings suggests that training for the purpose of increasing working memory can have specific short-term effects but no effects on g_f.

Environmental impact of fracking

From Wikipedia, the free encyclopedia

 https://en.wikipedia.org/wiki/Environmental_impact_of_fracking

 

Fracking
Shale gas drilling rig near Alvarado, Texas

The environmental impact of fracking is related to land use and water consumption, air emissions, including methane emissions, brine and fracturing fluid leakage, water contamination, noise pollution, and health. Water and air pollution are the biggest risks to human health from fracking. Research has determined that fracking negatively affects human health and drives climate change.

Fracking fluids include proppants and other substances, which include chemicals known to be toxic, as well as unknown chemicals that may be toxic. In the United States, such additives may be treated as trade secrets by companies who use them. Lack of knowledge about specific chemicals has complicated efforts to develop risk management policies and to study health effects. In other jurisdictions, such as the United Kingdom, these chemicals must be made public and their applications are required to be nonhazardous.

Water usage by fracking can be a problem in areas that experience water shortage. Surface water may be contaminated through spillage and improperly built and maintained waste pits, in jurisdictions where these are permitted. Further, ground water can be contaminated if fracturing fluids and formation fluids are able to escape during fracking. However, the possibility of groundwater contamination from the fracturing fluid upward migration is negligible, even in a long-term period. Produced water, the water that returns to the surface after fracking, is managed by underground injection, municipal and commercial wastewater treatment, and reuse in future wells. There is potential for methane to leak into ground water and the air, though escape of methane is a bigger problem in older wells than in those built under more recent legislation.

Fracking causes induced seismicity called microseismic events or microearthquakes. The magnitude of these events is too small to be detected at the surface, being of magnitude M-3 to M-1 usually. However, fluid disposal wells (which are often used in the USA to dispose of polluted waste from several industries) have been responsible for earthquakes up to 5.6M in Oklahoma and other states.

Governments worldwide are developing regulatory frameworks to assess and manage environmental and associated health risks, working under pressure from industry on the one hand, and from anti-fracking groups on the other. In some countries like France a precautionary approach has been favored and fracking has been banned. The United Kingdom's regulatory framework is based on the conclusion that the risks associated with fracking are manageable if carried out under effective regulation and if operational best practices are implemented. It has been suggested by the authors of meta-studies that in order to avoid further negative impacts, greater adherence to regulation and safety procedures are necessary.

Air emissions

A report for the European Union on the potential risks was produced in 2012. Potential risks are "methane emissions from the wells, diesel fumes and other hazardous pollutants, ozone precursors or odours from hydraulic fracturing equipment, such as compressors, pumps, and valves". Also gases and hydraulic fracturing fluids dissolved in flowback water pose air emissions risks. One study measured various air pollutants weekly for a year surrounding the development of a newly fractured gas well and detected nonmethane hydrocarbons, methylene chloride (a toxic solvent), and polycyclic aromatic hydrocarbons. These pollutants have been shown to affect fetal outcomes.

The relationship between hydraulic fracturing and air quality can influence acute and chronic respiratory illnesses, including exacerbation of asthma (induced by airborne particulates, ozone and exhaust from equipment used for drilling and transport) and COPD. For example, communities overlying the Marcellus shale have higher frequencies of asthma. Children, active young adults who spend time outdoors, and the elderly are particularly vulnerable. OSHA has also raised concerns about the long-term respiratory effects of occupational exposure to airborne silica at hydraulic fracturing sites. Silicosis can be associated with systemic autoimmune processes.

"In the UK, all oil and gas operators must minimise the release of gases as a condition of their licence from the Department of Energy and Climate Change (DECC). Natural gas may only be vented for safety reasons."

Also transportation of necessary water volume for hydraulic fracturing, if done by trucks, can cause emissions. Piped water supplies can reduce the number of truck movements necessary.

A report from the Pennsylvania Department of Environmental Protection indicated that there is little potential for radiation exposure from oil and gas operations.

Air pollution is of particular concern to workers at hydraulic fracturing well sites as the chemical emissions from storage tanks and open flowback pits combine with the geographically compounded air concentrations from surrounding wells. Thirty seven percent of the chemicals used in hydraulic fracturing operations are volatile and can become airborne.

Researchers Chen and Carter from the Department of Civil and Environmental Engineering, University of Tennessee, Knoxville used atmospheric dispersion models (AERMOD) to estimate the potential exposure concentration of emissions for calculated radial distances of 5 m to 180m from emission sources. The team examined emissions from 60,644 hydraulic fracturing wells and found “results showed the percentage of wells and their potential acute non-cancer, chronic non-cancer, acute cancer, and chronic cancer risks for exposure to workers were 12.41%, 0.11%, 7.53%, and 5.80%, respectively. Acute and chronic cancer risks were dominated by emissions from the chemical storage tanks within a 20 m radius.

Climate change

Hydraulic fracturing is a driver of climate change. However, whether natural gas produced by hydraulic fracturing causes higher well-to-burner emissions than gas produced from conventional wells is a matter of contention. Some studies have found that hydraulic fracturing has higher emissions due to methane released during completing wells as some gas returns to the surface, together with the fracturing fluids. Depending on their treatment, the well-to-burner emissions are 3.5%–12% higher than for conventional gas.

A debate has arisen particularly around a study by professor Robert W. Howarth finding shale gas significantly worse for global warming than oil or coal. Other researchers have criticized Howarth's analysis, including Cathles et al., whose estimates were substantially lower." A 2012 industry funded report co-authored by researchers at the United States Department of Energy's National Renewable Energy Laboratory found emissions from shale gas, when burned for electricity, were "very similar" to those from so-called "conventional well" natural gas, and less than half the emissions of coal.

Studies which have estimated lifecycle methane leakage from natural gas development and production have found a wide range of leakage rates. According to the Environmental Protection Agency's Greenhouse Gas Inventory, the methane leakage rate is about 1.4%. A 16-part assessment of methane leakage from natural gas production initiated by the Environmental Defense Fund found that fugitive emissions in key stages of the natural gas production process are significantly higher than estimates in the EPA's national emission inventory, with a leakage rate of 2.3 percent of overall natural gas output.

Water consumption

Massive hydraulic fracturing typical of shale wells uses between 1.2 and 3.5 million US gallons (4,500 and 13,200 m³) of water per well, with large projects using up to 5 million US gallons (19,000 m³). Additional water is used when wells are refractured. An average well requires 3 to 8 million US gallons (11,000 to 30,000 m³) of water over its lifetime. According to the Oxford Institute for Energy Studies, greater volumes of fracturing fluids are required in Europe, where the shale depths average 1.5 times greater than in the U.S. Whilst the published amounts may seem large, they are small in comparison with the overall water usage in most areas. A study in Texas, which is a water shortage area, indicates "Water use for shale gas is <1% of statewide water withdrawals; however, local impacts vary with water availability and competing demands."

A report by the Royal Society and the Royal Academy of Engineering shows the usage expected for hydraulic fracturing a well is approximately the amount needed to run a 1,000 MW coal-fired power plant for 12 hours. A 2011 report from the Tyndall Centre estimates that to support a 9 billion cubic metres per annum (320×10⁹ cu ft/a) gas production industry, between 1.25 to 1.65 million cubic metres (44×10⁶ to 58×10⁶ cu ft) would be needed annually, which amounts to 0.01% of the total water abstraction nationally.

Concern has been raised over the increasing quantities of water for hydraulic fracturing in areas that experience water stress. Use of water for hydraulic fracturing can divert water from stream flow, water supplies for municipalities and industries such as power generation, as well as recreation and aquatic life. The large volumes of water required for most common hydraulic fracturing methods have raised concerns for arid regions, such as the Karoo in South Africa, and in drought-prone Texas, in North America. It may also require water overland piping from distant sources.

A 2014 life cycle analysis of natural gas electricity by the National Renewable Energy Laboratory concluded that electricity generated by natural gas from massive hydraulically fractured wells consumed between 249 gallons per megawatt-hour (gal/MWhr) (Marcellus trend) and 272 gal/MWhr (Barnett Shale). The water consumption for the gas from massive hydraulic fractured wells was from 52 to 75 gal/MWhr greater (26 percent to 38 percent greater) than the 197 gal/MWhr consumed for electricity from conventional onshore natural gas.

Some producers have developed hydraulic fracturing techniques that could reduce the need for water. Using carbon dioxide, liquid propane or other gases instead of water have been proposed to reduce water consumption. After it is used, the propane returns to its gaseous state and can be collected and reused. In addition to water savings, gas fracturing reportedly produces less damage to rock formations that can impede production. Recycled flowback water can be reused in hydraulic fracturing. It lowers the total amount of water used and reduces the need to dispose of wastewater after use. The technique is relatively expensive, however, since the water must be treated before each reuse and it can shorten the life of some types of equipment.

Water contamination

Injected fluid

In the United States, hydraulic fracturing fluids include proppants, radionuclide tracers, and other chemicals, many of which are toxic. The type of chemicals used in hydraulic fracturing and their properties vary. While most of them are common and generally harmless, some chemicals are carcinogenic. Out of 2,500 products used as hydraulic fracturing additives in the United States, 652 contained one or more of 29 chemical compounds which are either known or possible human carcinogens, regulated under the Safe Drinking Water Act for their risks to human health, or listed as hazardous air pollutants under the Clean Air Act. Another 2011 study identified 632 chemicals used in United States natural gas operations, of which only 353 are well-described in the scientific literature. A study that assessed health effects of chemicals used in fracturing found that 73% of the products had between 6 and 14 different adverse health effects including skin, eye, and sensory organ damage; respiratory distress including asthma; gastrointestinal and liver disease; brain and nervous system harms; cancers; and negative reproductive effects.

An expansive study conducted by the Yale School of Public Health in 2016 found numerous chemicals involved in or released by hydraulic fracturing are carcinogenic. Of the 119 compounds identified in this study with sufficient data, “44% of the water pollutants...were either confirmed or possible carcinogens.” However, the majority of chemicals lacked sufficient data on carcinogenic potential, highlighting the knowledge gap in this area. Further research is needed to identify both carcinogenic potential of chemicals used in hydraulic fracturing and their cancer risk.

The European Union regulatory regime requires full disclosure of all additives. According to the EU groundwater directive of 2006, "in order to protect the environment as a whole, and human health in particular, detrimental concentrations of harmful pollutants in groundwater must be avoided, prevented or reduced." In the United Kingdom, only chemicals that are "non hazardous in their application" are licensed by the Environment Agency.

Flowback

Less than half of injected water is recovered as flowback or later production brine, and in many cases recovery is <30%. As the fracturing fluid flows back through the well, it consists of spent fluids and may contain dissolved constituents such as minerals and brine waters. In some cases, depending on the geology of the formation, it may contain uranium, radium, radon and thorium. Estimates of the amount of injected fluid returning to the surface range from 15-20% to 30–70%.

Approaches to managing these fluids, commonly known as produced water, include underground injection, municipal and commercial wastewater treatment and discharge, self-contained systems at well sites or fields, and recycling to fracture future wells. The vacuum multi-effect membrane distillation system as a more effective treatment system has been proposed for treatment of flowback. However, the quantity of waste water needing treatment and the improper configuration of sewage plants have become an issue in some regions of the United States. Part of the wastewater from hydraulic fracturing operations is processed there by public sewage treatment plants, which are not equipped to remove radioactive material and are not required to test for it.

Produced water spills and subsequent contamination of groundwater also presents a risk for exposure to carcinogens. Research that modeled the solute transport of BTEX (benzene, toluene, ethylbenzene, and xylene) and naphthalene for a range of spill sizes on contrasting soils overlying groundwater at different depths found that benzene and toluene were expected to reach human health relevant concentration in groundwater because of their high concentrations in produced water, relatively low solid/liquid partition coefficient and low EPA drinking water limits for these contaminants. Benzene is a known carcinogen which affects the central nervous system in the short term and can affect the bone marrow, blood production, immune system, and urogenital systems with long term exposure.

Surface spills

Surface spills related to the hydraulic fracturing occur mainly because of equipment failure or engineering misjudgments.

Volatile chemicals held in waste water evaporation ponds can evaporate into the atmosphere, or overflow. The runoff can also end up in groundwater systems. Groundwater may become contaminated by trucks carrying hydraulic fracturing chemicals and wastewater if they are involved in accidents on the way to hydraulic fracturing sites or disposal destinations.

In the evolving European Union legislation, it is required that "Member States should ensure that the installation is constructed in a way that prevents possible surface leaks and spills to soil, water or air." Evaporation and open ponds are not permitted. Regulations call for all pollution pathways to be identified and mitigated. The use of chemical proof drilling pads to contain chemical spills is required. In the UK, total gas security is required, and venting of methane is only permitted in an emergency.

Methane

In September 2014, a study from the US Proceedings of the National Academy of Sciences released a report that indicated that methane contamination can be correlated to distance from a well in wells that were known to leak. This however was not caused by the hydraulic fracturing process, but by poor cementation of casings.

Groundwater methane contamination has adverse effect on water quality and in extreme cases may lead to potential explosion. A scientific study conducted by researchers of Duke University found high correlations of gas well drilling activities, including hydraulic fracturing, and methane pollution of the drinking water. According to the 2011 study of the MIT Energy Initiative, "there is evidence of natural gas (methane) migration into freshwater zones in some areas, most likely as a result of substandard well completion practices i.e. poor quality cementing job or bad casing, by a few operators." A 2013 Duke study suggested that either faulty construction (defective cement seals in the upper part of wells, and faulty steel linings within deeper layers) combined with a peculiarity of local geology may be allowing methane to seep into waters; the latter cause may also release injected fluids to the aquifer. Abandoned gas and oil wells also provide conduits to the surface in areas like Pennsylvania, where these are common.

A study by Cabot Oil and Gas examined the Duke study using a larger sample size, found that methane concentrations were related to topography, with the highest readings found in low-lying areas, rather than related to distance from gas production areas. Using a more precise isotopic analysis, they showed that the methane found in the water wells came from both the formations where hydraulic fracturing occurred, and from the shallower formations. The Colorado Oil & Gas Conservation Commission investigates complaints from water well owners, and has found some wells to contain biogenic methane unrelated to oil and gas wells, but others that have thermogenic methane due to oil and gas wells with leaking well casing. A review published in February 2012 found no direct evidence that hydraulic fracturing actual injection phase resulted in contamination of ground water, and suggests that reported problems occur due to leaks in its fluid or waste storage apparatus; the review says that methane in water wells in some areas probably comes from natural resources.

Another 2013 review found that hydraulic fracturing technologies are not free from risk of contaminating groundwater, and described the controversy over whether the methane that has been detected in private groundwater wells near hydraulic fracturing sites has been caused by drilling or by natural processes.

Radionuclides

Main article: Naturally occurring radioactive material

There are naturally occurring radioactive materials (NORM), for example radium, radon, uranium, and thorium, in shale deposits. Brine co-produced and brought to the surface along with the oil and gas sometimes contains naturally occurring radioactive materials; brine from many shale gas wells, contains these radioactive materials. The U.S. Environmental Protection Agency and regulators in North Dakota consider radioactive material in flowback a potential hazard to workers at hydraulic fracturing drilling and waste disposal sites and those living or working nearby if the correct procedures are not followed. A report from the Pennsylvania Department of Environmental Protection indicated that there is little potential for radiation exposure from oil and gas operations.

Land use

In the UK, the likely well spacing visualised by the December 2013 DECC Strategic Environmental Assessment report indicated that well pad spacings of 5 km were likely in crowded areas, with up to 3 hectares (7.4 acres) per well pad. Each pad could have 24 separate wells. This amounts to 0.16% of land area. A study published in 2015 on the Fayetteville Shale found that a mature gas field impacted about 2% of the land area and substantially increased edge habitat creation. Average land impact per well was 3 hectares (about 7 acres)  In another case study for a watershed in Ohio, lands disturbed over 20 years amount to 9.7% of the watershed area, with only 0.24% attributed to fracking wellpad construction. Research indicates that effects on ecosystem services costs (i.e. those processes that the natural world provides to humanity) has reached over $250 million per year in the U.S.

Seismicity

Hydraulic fracturing causes induced seismicity called microseismic events or microearthquakes. These microseismic events are often used to map the horizontal and vertical extent of the fracturing. The magnitude of these events is usually too small to be detected at the surface, although the biggest micro-earthquakes may have the magnitude of about -1.5 (M_w).

Induced seismicity from hydraulic fracturing

As of August 2016, there were at least nine known cases of fault reactivation by hydraulic fracturing that caused induced seismicity strong enough to be felt by humans at the surface: In Canada, there have been three in Alberta (M 4.8 and M 4.4 and M 4.4) and three in British Columbia (M 4.6, M 4.4 and M 3.8); In the United States there has been: one in Oklahoma (M 2.8) and one in Ohio (M 3.0), and; In the United Kingdom, there have been two in Lancashire (M 2.3 and M 1.5).

Induced seismicity from water disposal wells

According to the USGS only a small fraction of roughly 30,000 waste fluid disposal wells for oil and gas operations in the United States have induced earthquakes that are large enough to be of concern to the public. Although the magnitudes of these quakes has been small, the USGS says that there is no guarantee that larger quakes will not occur. In addition, the frequency of the quakes has been increasing. In 2009, there were 50 earthquakes greater than magnitude 3.0 in the area spanning Alabama and Montana, and there were 87 quakes in 2010. In 2011 there were 134 earthquakes in the same area, a sixfold increase over 20th century levels. There are also concerns that quakes may damage underground gas, oil, and water lines and wells that were not designed to withstand earthquakes.

A 2012 US Geological Survey study reported that a "remarkable" increase in the rate of M ≥ 3 earthquakes in the US midcontinent "is currently in progress", having started in 2001 and culminating in a 6-fold increase over 20th century levels in 2011. The overall increase was tied to earthquake increases in a few specific areas: the Raton Basin of southern Colorado (site of coalbed methane activity), and gas-producing areas in central and southern Oklahoma, and central Arkansas. While analysis suggested that the increase is "almost certainly man-made", the USGS noted: "USGS's studies suggest that the actual hydraulic fracturing process is only very rarely the direct cause of felt earthquakes." The increased earthquakes were said to be most likely caused by increased injection of gas-well wastewater into disposal wells. The injection of waste water from oil and gas operations, including from hydraulic fracturing, into saltwater disposal wells may cause bigger low-magnitude tremors, being registered up to 3.3 (M_w).

Noise

Each well pad (in average 10 wells per pad) needs during preparatory and hydraulic fracturing process about 800 to 2,500 days of activity, which may affect residents. In addition, noise is created by transport related to the hydraulic fracturing activities. Noise pollution from hydraulic fracturing operations (e.g., traffic, flares/burn-offs) is often cited as a source of psychological distress, as well as poor academic performance in children. For example, the low-frequency noise that comes from well pumps contributes to irritation, unease, and fatigue.

The UK Onshore Oil and Gas (UKOOG) is the industry representative body, and it has published a charter that shows how noise concerns will be mitigated, using sound insulation, and heavily silenced rigs where this is needed.

Safety issues

In July 2013, the United States Federal Railroad Administration listed oil contamination by hydraulic fracturing chemicals as "a possible cause" of corrosion in oil tank cars.

Community impacts

Impacted communities are often already vulnerable, including poor, rural, or indigenous persons, who may continue to experience the deleterious effects of hydraulic fracturing for generations. Competition for resources between farmers and oil companies contributes to stress for agricultural workers and their families, as well as to a community-level “us versus them” mentality that creates community distress (Morgan et al. 2016). Rural communities that host hydraulic fracturing operations often experience a “boom/bust cycle,” whereby their population surges, consequently exerting stress on community infrastructure and service provision capabilities (e.g., medical care, law enforcement).

Indigenous and agricultural communities may be particularly impacted by hydraulic fracturing, given their historical attachment to, and dependency on, the land they live on, which is often damaged as a result of the hydraulic fracturing process. Native Americans, particularly those living on rural reservations, may be particularly vulnerable to the effects of fracturing; that is, on the one hand, tribes may be tempted to engage with the oil companies to secure a source of income but, on the other hand, must often engage in legal battles to protect their sovereign rights and the natural resources of their land.

Policy and science

Main article: Regulation of hydraulic fracturing

There are two main approaches to regulation that derive from policy debates about how to manage risk and a corresponding debate about how to assess risk.

The two main schools of regulation are science-based assessment of risk and the taking of measures to prevent harm from those risks through an approach like hazard analysis, and the precautionary principle, where action is taken before risks are well-identified. The relevance and reliability of risk assessments in communities where hydraulic fracturing occurs has also been debated amongst environmental groups, health scientists, and industry leaders. The risks, to some, are overplayed and the current research is insufficient in showing the link between hydraulic fracturing and adverse health effects, while to others the risks are obvious and risk assessment is underfunded.

Different regulatory approaches have thus emerged. In France and Vermont for instance, a precautionary approach has been favored and hydraulic fracturing has been banned based on two principles: the precautionary principle and the prevention principle. Nevertheless, some States such as the U.S. have adopted a risk assessment approach, which had led to many regulatory debates over the issue of hydraulic fracturing and its risks.

In the UK, the regulatory framework is largely being shaped by a report commissioned by the UK Government in 2012, whose purpose was to identify the problems around hydraulic fracturing and to advise the country's regulatory agencies. Jointly published by the Royal Society and the Royal Academy of Engineering, under the chairmanship of Professor Robert Mair, the report features ten recommendations covering issues such as groundwater contamination, well integrity, seismic risk, gas leakages, water management, environmental risks, best practice for risk management, and also includes advice for regulators and research councils. The report was notable for stating that the risks associated with hydraulic fracturing are manageable if carried out under effective regulation and if operational best practices are implemented.

A 2013 review concluded that, in the US, confidentiality requirements dictated by legal investigations have impeded peer-reviewed research into environmental impacts.

There are numerous scientific limitations to the study of the environmental impact of hydraulic fracturing. The main limitation is the difficulty in developing effective monitoring procedures and protocols, for which there are several main reasons:

• Variability among fracturing sites in terms of ecosystems, operation sizes, pad densities, and quality-control measures makes it difficult to develop a standard protocol for monitoring.
• As more fracturing sites develop, the chance for interaction between sites increases, greatly compounding the effects and making monitoring of one site difficult to control. These cumulative effects can be difficult to measure, as many of the impacts develop very slowly.
• Due to the vast number of chemicals involved in hydraulic fracturing, developing baseline data is challenging. In addition, there is a lack of research on the interaction of the chemicals used in hydraulic fracturing fluid and the fate of the individual components.

Environmental impact of the energy industry

From Wikipedia, the free encyclopedia
https://en.wikipedia.org/wiki/Environmental_impact_of_the_energy_industry

World consumption of primary energy by energy type.

Energy consumption per capita per country (2001). Red hues indicate increase, green hues decrease of consumption during the 1990s.

The environmental impact of the energy industry is significant, as energy and natural resource consumption are closely related. Producing, transporting, or consuming energy all have an environmental impact. Energy has been harnessed by human beings for millennia. Initially it was with the use of fire for light, heat, cooking and for safety, and its use can be traced back at least 1.9 million years. In recent years there has been a trend towards the increased commercialization of various renewable energy sources. Scientific consensus on some of the main human activities that contribute to global warming are considered to be increasing concentrations of greenhouse gases, causing a warming effect, global changes to land surface, such as deforestation, for a warming effect, increasing concentrations of aerosols, mainly for a cooling effect.

Rapidly advancing technologies can potentially achieve a transition of energy generation, water and waste management, and food production towards better environmental and energy usage practices using methods of systems ecology and industrial ecology.

Issues

Climate change

Global average surface temperature datasets from various scientific organizations show the progress and extent of global warming.

Main article: Attribution of recent climate change

The warming influence (called radiative forcing) of long-lived greenhouse gases has nearly doubled in 40 years, with carbon dioxide and methane being the dominant drivers of global warming.

The scientific consensus on global warming and climate change is that it is caused by anthropogenic greenhouse gas emissions, the majority of which comes from burning fossil fuels with deforestation and some agricultural practices being also major contributors. A 2013 study showed that two thirds of the industrial greenhouse gas emissions are due to the fossil-fuel (and cement) production of just ninety companies around the world (between 1751 and 2010, with half emitted since 1986).

Although there is a highly publicized denial of climate change, the vast majority of scientists working in climatology accept that it is due to human activity. The IPCC report Climate Change 2007: Climate Change Impacts, Adaptation and Vulnerability predicts that climate change will cause shortages of food and water and increased risk of flooding that will affect billions of people, particularly those living in poverty.

One measurement of greenhouse gas related and other Externality comparisons between energy sources can be found in the ExternE project by the Paul Scherrer Institut and the University of Stuttgart which was funded by the European Commission. According to that study, hydroelectric electricity produces the lowest CO₂ emissions, wind produces the second-lowest, nuclear energy produces the third-lowest and solar photovoltaic produces the fourth-lowest.

Similarly, the same research study (ExternE, Externalities of Energy), undertaken from 1995 to 2005 found that the cost of producing electricity from coal or oil would double over its present value, and the cost of electricity production from gas would increase by 30% if external costs such as damage to the environment and to human health, from the airborne particulate matter, nitrogen oxides, chromium VI and arsenic emissions produced by these sources, were taken into account. It was estimated in the study that these external, downstream, fossil fuel costs amount up to 1–2% of the EU's entire Gross Domestic Product (GDP), and this was before the external cost of global warming from these sources was even included. The study also found that the environmental and health costs of nuclear power, per unit of energy delivered, was €0.0019/kWh, which was found to be lower than that of many renewable sources including that caused by biomass and photovoltaic solar panels, and was thirty times lower than coal at €0.06/kWh, or 6 cents/kWh, with the energy sources of the lowest external environmental and health costs associated with it being wind power at €0.0009/kWh.

Biofuel use

Further information: Environmental impact of biofuels

Biofuel is defined as solid, liquid or gaseous fuel obtained from relatively recently lifeless or living biological material and is different from fossil fuels, which are derived from long-dead biological material. Various plants and plant-derived materials are used for biofuel manufacturing.

Bio-diesel

Main article: Environmental effects of biodiesel

See also: Indirect land use change impacts of biofuels and Sustainable biofuel

High use of bio-diesel leads to land use changes including deforestation.

Firewood

Unsustainable firewood harvesting can lead to loss of biodiversity and erosion due to loss of forest cover. An example of this is a 40-year study done by the University of Leeds of African forests, which account for a third of the world's total tropical forest which demonstrates that Africa is a significant carbon sink. A climate change expert, Lee White states that "To get an idea of the value of the sink, the removal of nearly 5 billion tonnes of carbon dioxide from the atmosphere by intact tropical forests is at issue.

According to the U.N. the African continent is losing forest twice as fast as the rest of the world. "Once upon a time, Africa boasted seven million square kilometers of forest but a third of that has been lost, most of it to charcoal."

Fossil fuel use

Global fossil carbon emission by fuel type, 1800–2007 AD.

The three fossil fuel types are coal, petroleum and natural gas. It was estimated by the Energy Information Administration that in 2006 primary sources of energy consisted of petroleum 36.8%, coal 26.6%, natural gas 22.9%, amounting to an 86% share for fossil fuels in primary energy production in the world.

In 2013 the burning of fossil fuels produced around 32 billion tonnes (32 gigatonnes) of carbon dioxide and additional air pollution. This caused negative externalities of $4.9 trillion due to global warming and health problems (> 150 $/ton carbon dioxide). Carbon dioxide is one of the greenhouse gases that enhances radiative forcing and contributes to global warming, causing the average surface temperature of the Earth to rise in response, which climate scientists agree will cause major adverse effects.

Coal

A coal surface mining site in Bihar, India

A mountaintop removal mining operation in the United States

The health and environmental impact of the coal industry includes issues such as land use, waste management, water and air pollution, caused by the coal mining, processing and the use of its products. In addition to atmospheric pollution, coal burning produces hundreds of millions of tons of solid waste products annually, including fly ash, bottom ash, and flue-gas desulfurization sludge, that contain mercury, uranium, thorium, arsenic, and other heavy metals. Coal is the largest contributor to the human-made increase of carbon dioxide in Earth's atmosphere.

There are severe health effects caused by burning coal. According to a report by the World Health Organization in 2008, coal particulates pollution are estimated to shorten approximately 10,000 lives annually worldwide. A 2004 study commissioned by environmental groups, but contested by the United States Environmental Protection Agency, concluded that coal burning costs 24,000 lives a year in the United States. More recently, an academic study estimated that the premature deaths from coal related air pollution was about 52,000. When compared to electricity produced from natural gas via hydraulic fracturing, coal electricity is 10–100 times more toxic, largely due to the amount of particulate matter emitted during combustion. When coal is compared to solar photovoltaic generation, the latter could save 51,999 American lives per year if solar were to replace coal-based energy generation in the U.S. Due to the decline of jobs related to coal mining a study found that approximately one American suffers a premature death from coal pollution for every job remaining in coal mining.

In addition, the list of historical coal mining disasters is a long one, although work related coal deaths has declined substantially as safety measures have been enacted and underground mining has given up market share to surface mining. Underground mining hazards include suffocation, gas poisoning, roof collapse and gas explosions. Open cut hazards are principally mine wall failures and vehicle collisions. In the United States, an average of 26 coal miners per year died in the decade 2005–2014.

Petroleum

Flaring of gas from offshore oil extraction platforms

A beach after an oil spill.

Accumulation of plastic waste on a beach.

The environmental impact of the petroleum industry is extensive and expansive due to petroleum having many uses. Crude oil and natural gas are primary energy and raw material sources that enable numerous aspects of modern daily life and the world economy. Their supply has grown quickly over the last 150 years to meet the demands of the rapidly increasing human population, creativity, knowledge, and consumerism.

Substantial quantities of toxic and non-toxic waste are generated during the extraction, refinement, and transportation stages of oil and gas. Some industry by-products, such as volatile organic compounds, nitrogen & sulfur compounds, and spilled oil can pollute the air, water and soil at levels that are harmful to life, when improperly managed. Climate warming, ocean acidification, and sea level rise are global changes enhanced by the industry's emissions of greenhouse gases like carbon dioxide (CO₂) and methane, and micro-particulate aerosols like black carbon.

Among all human activities, fossil fuel combustion is the largest contributor to the ongoing buildup of carbon in the earth's biosphere. The International Energy Agency and others report that oil & gas use comprises over 55% (18 Billion Tons) of the recorded 32.8 Billion Tons (BT) of CO₂ released into the atmosphere from all energy sources in year 2017. Coal use comprised most of the remaining 45%. Total emissions continue to rise nearly every year: from 1.7% to 33.1 BT in 2018.

Through its operations, the petroleum industry directly contributed about 8% (2.7 BT) of the 32.8 BT in 2017. Also, due to its intentional and other releases of natural gas, the industry directly contributed at least 79 Million Tons of methane (2.4 BT CO₂-equivalent) that same year; an amount equal to about 14% of all known anthropogenic and natural emissions of the potent warming gas.

Along with fuels like gasoline and liquified natural gas, petroleum enables many consumer chemicals and products, such as fertilizers and plastics. Most alternative technologies for energy generation, transportation, and storage can only be realized at this time because of its diverse usefulness.

Conservation, efficiency, and minimizing waste impacts of petroleum products are effective industry and consumer actions toward achieving better environmental sustainability.

Gas

Further information: Environmental impact of fracking

Natural gas is often described as the cleanest fossil fuel, producing less carbon dioxide per joule delivered than either coal or oil, and far fewer pollutants than other fossil fuels. However, in absolute terms, it does contribute substantially to global carbon emissions, and this contribution is projected to grow. According to the IPCC Fourth Assessment Report, in 2004 natural gas produced about 5,300 Mt/yr of CO₂ emissions, while coal and oil produced 10,600 and 10,200 respectively (Figure 4.4); but by 2030, according to an updated version of the SRES B2 emissions scenario, natural gas would be the source of 11,000 Mt/yr, with coal and oil now 8,400 and 17,200 respectively. (Total global emissions for 2004 were estimated at over 27,200 Mt.)

In addition, natural gas itself is a greenhouse gas far more potent than carbon dioxide when released into the atmosphere but is released in smaller amounts. The environmental impacts of Natural gas also vary substantially on their extraction processes, much natural gas is a byproduct of heavily polluting petroleum extraction and newer techniques for hydraulic fracturing have made natural gas reserves that were previously unaccusable available, but with many more negative environmental and health impacts that traditional natural gas extraction.

Electricity generation

Main article: Environmental impact of electricity generation

The environmental impact of electricity generation is significant because modern society uses large amounts of electrical power. This power is normally generated at power plants that convert some other kind of energy into electrical power. Each such system has advantages and disadvantages, but many of them pose environmental concerns.

Reservoirs

The Wachusett Dam in Clinton, Massachusetts.

The environmental impact of reservoirs comes under ever-increasing scrutiny as the global demand for water and energy increases and the number and size of reservoirs increases.

Dams and reservoirs can be used to supply drinking water, generate hydroelectric power, increase the water supply for irrigation, provide recreational opportunities, and flood control. In 1960 the construction of Llyn Celyn and the flooding of Capel Celyn provoked political uproar which continues to this day. More recently, the construction of Three Gorges Dam and other similar projects throughout Asia, Africa and Latin America have generated considerable environmental and political debate. Currently, 48 percent of rivers and their hydro-ecological systems are affected by reservoirs and dams.

Nuclear power

Main article: Environmental impact of nuclear power

Nuclear power activities involving the environment; mining, enrichment, generation and geological disposal.

The environmental impact of nuclear power results from the nuclear fuel cycle, operation, and the effects of nuclear accidents.

The routine health risks and greenhouse gas emissions from nuclear fission power are significantly smaller than those associated with coal, oil and gas. However, there is a "catastrophic risk" potential if containment fails, which in nuclear reactors can be brought about by over-heated fuels melting and releasing large quantities of fission products into the environment. The most long-lived radioactive wastes, including spent nuclear fuel, must be contained and isolated from humans and the environment for hundreds of thousands of years. The public is sensitive to these risks and there has been considerable public opposition to nuclear power. Despite this potential for disaster, normal fossil fuel related pollution is still considerably more harmful than any previous nuclear disaster.

The 1979 Three Mile Island accident and 1986 Chernobyl disaster, along with high construction costs, ended the rapid growth of global nuclear power capacity. A further disastrous release of radioactive materials followed the 2011 Japanese tsunami which damaged the Fukushima I Nuclear Power Plant, resulting in hydrogen gas explosions and partial meltdowns classified as a Level 7 event. The large-scale release of radioactivity resulted in people being evacuated from a 20 km exclusion zone set up around the power plant, similar to the 30 km radius Chernobyl Exclusion Zone still in effect.

Mitigation

Energy conservation

Main article: Energy conservation

Energy conservation refers to efforts made to reduce energy consumption. Energy conservation can be achieved through increased efficient energy use, in conjunction with decreased energy consumption and/or reduced consumption from conventional energy sources.

Energy conservation can result in increased financial capital, environmental quality, national security, personal security, and human comfort. Individuals and organizations that are direct consumers of energy choose to conserve energy to reduce energy costs and promote economic security. Industrial and commercial users can increase energy use efficiency to maximize profit.

The increase of global energy use can also be slowed by tackling human population growth, by using non-coercive measures such as better provision of family planning services and by empowering (educating) women in developing countries.

An EU survey conducted on climate and energy consumption in 2022 found that 63% of people in the European Union want energy costs to be dependent on use, with the greatest consumers paying more. This is compared to 83% in China, 63% in the UK and 57% in the US.

Energy policy

Main article: Energy policy

Energy policy is the manner in which a given entity (often governmental) has decided to address issues of energy development including energy production, distribution and consumption. The attributes of energy policy may include legislation, international treaties, incentives to investment, guidelines for energy conservation, taxation and other public policy techniques.