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Friday, October 7, 2022

Sustainability measurement

From Wikipedia, the free encyclopedia
 
Trees being felled in Kalimantan, the Indonesian part of Borneo, in 2013, to make way for a new coal mining project

Sustainability measurement are tools and methods that attempt to measure the degree of sustainability of processes, products, services, businesses and so forth. Sustainability is difficult to quantify, perhaps even immeasurable. The metrics used to try and measure sustainability involve the sustainability of environmental, social and economic domains, (both individually and in various combinations) and are still evolving. They include indicators, benchmarks, audits, sustainability standards and certification systems like Fairtrade and Organic, indexes and accounting, as well as assessment, appraisal and other reporting systems. They are applied over a wide range of spatial and temporal scales. Some of the widely used sustainability measures include corporate sustainability reporting, Triple Bottom Line accounting, World Sustainability Society, and estimates of the quality of sustainability governance for individual countries using the Environmental Sustainability Index and Environmental Performance Index. The UN Human Development Index and the ecological footprints are methods to monitor sustainable development over time.

Two related concepts to understand if the mode of life of humanity is sustainable, are planetary boundaries and ecological footprint. If the boundaries are not crossed and the ecological footprint is not exceeding the carrying capacity of the biosphere, the mode of life is regarded as sustainable.

A set of well defined and harmonized indicators can help to make sustainability tangible. Those indicators are expected to be identified and adjusted through empirical observations (trial and error). The most common critiques are related to issues like data quality, comparability, objective function and the necessary resources. However a more general criticism is coming from the project management community: "How can a sustainable development be achieved at global level if we cannot monitor it in any single project?".

Sustainability need and framework

Sustainability development has become the primary yardstick of improvement for industries and is being integrated into effective business strategies. The needs for sustainability measurement include improvement in the operations, benchmarking performances, tracking progress, and evaluating process, among others. For the purposes of building a proper sustainability indicator, framework is developed and the steps are as follows:

  1. Defining the system- A proper and definite system is defined. A proper system boundary is drawn for further analysis.
  2. Elements of the system- The whole input, output of materials, emissions, energy and other auxiliary elements are properly analysed. The working conditions, process parameters and characteristics are defined in this step.
  3. Indicators selection- The indicators is selected of which measurement has to be done. This forms the metric for this system whose analysis is done in the further steps.
  4. Assessment and Measurement- Proper assessing tools are used and tests or experiments are performed for the pre-defined indicators to give a value for the indicators measurement.
  5. Analysis and reviewing the results- Once the results have been obtained, proper analysis and interpretation is done and tools are used to improve and revise the processes present in the system.

Sustainability indicators and their function

The principal objective of sustainability indicators is to inform public policy-making as part of the process of sustainability governance. Sustainability indicators can provide information on any aspect of the interplay between the environment and socio-economic activities. Building strategic indicator sets generally deals with just a few simple questions: what is happening? (descriptive indicators), does it matter and are we reaching targets? (performance indicators), are we improving? (efficiency indicators), are measures working? (policy effectiveness indicators), and are we generally better off? (total welfare indicators).

The International Institute for Sustainable Development and the United Nations Conference on Trade and Development established the Committee on Sustainability Assessment (COSA) in 2006 to evaluate sustainability initiatives operating in agriculture and develop indicators for their measurable social, economic and environmental objectives.

One popular general framework used by The European Environment Agency uses a slight modification of the Organisation for Economic Co-operation and Development DPSIR system. This breaks up environmental impact into five stages. Social and economic developments (consumption and production) (D)rive or initiate environmental (P)ressures which, in turn, produces a change in the (S)tate of the environment which leads to (I)mpacts of various kinds. Societal (R)esponses (policy guided by sustainability indicators) can be introduced at any stage of this sequence of events.

Politics

A study concluded that social indicators and, therefore, sustainable development indicators, are scientific constructs whose principal objective is to inform public policy-making. The International Institute for Sustainable Development has similarly developed a political policy framework, linked to a sustainability index for establishing measurable entities and metrics. The framework consists of six core areas:

  1. International trade and investment
  2. Economic policy
  3. Climate change and energy
  4. Measurement and assessment
  5. Natural resource management
  6. Communication technologies.

The United Nations Global Compact Cities Programme has defined sustainable political development in a way that broadens the usual definition beyond states and governance. The political is defined as the domain of practices and meanings associated with basic issues of social power as they pertain to the organisation, authorisation, legitimation and regulation of a social life held in common. This definition is in accord with the view that political change is important for responding to economic, ecological and cultural challenges. It also means that the politics of economic change can be addressed. They have listed seven subdomains of the domain of politics:

  1. Organization and governance
  2. Law and justice
  3. Communication and critique
  4. Representation and negotiation
  5. Security and accord
  6. Dialogue and reconciliation
  7. Ethics and accountability

Metrics at the global scale

There are numerous indicators which could be used as basis for sustainability measurement. Few commonly used indicators are:

Environmental sustainability indicators:

Economic indicators:

Social indicators:

Due to the large numbers of various indicators that could be used for sustainability measurement, proper assessment and monitoring is required. In order to organize the chaos and disorder in selecting the metrics, specific organizations have been set up which groups the metrics under different categories and defines proper methodology to implement it for measurement. They provide modelling techniques and indexes to compare the measurement and have methods to convert the scientific measurement results into easy to understand terms.

United Nations indicators

The United Nations has developed extensive sustainability measurement tools in relation to sustainable development as well as a System of Integrated Environmental and Economic Accounting.

United Nations Commission on Sustainable Development

The UN Commission on Sustainable Development (CSD) has published a list of 140 indicators which covers environmental, social, economical and institutional aspects of sustainable development.

Benchmarks, indicators, indexes, auditing etc.

In the last couple of decades, there has arisen a crowded toolbox of quantitative methods used to assess sustainability — including measures of resource use like life cycle assessment, measures of consumption like the ecological footprint and measurements of quality of environmental governance like the Environmental Performance Index. The following is a list of quantitative "tools" used by sustainability scientists - the different categories are for convenience only as defining criteria will intergrade. It would be too difficult to list all those methods available at different levels of the organization so those listed here are at the global level only.

A benchmark is a point of reference for a measurement. Once a benchmark is established it is possible to assess trends and measure progress. Baseline global data on a range of sustainability parameters is available in the list of global sustainability statistics.
A sustainability index is an aggregate sustainability indicator that combines multiple sources of data. There is a Consultative Group on Sustainable Development Indices
Many environmental problems ultimately relate to the human effect on those global biogeochemical cycles that are critical to life. Over the last decade monitoring these cycles have become a more urgent target for research:
Sustainability auditing and reporting are used to evaluate the sustainability performance of a company, organization, or other entity using various performance indicators. Popular auditing procedures available at the global level include:
Some accounting methods attempt to include environmental costs rather than treating them as externalities

Life cycle analysis

A life cycle analysis is often conducted when assessing the sustainability of a product or prototype. The decision to choose materials is heavily weighted on its longevity, renewability, and efficiency. These factors ensure that researchers are conscious of community values that align with positive environmental, social, and economic impacts.

Resource metrics

Part of this process can relate to resource use such as energy accounting or to economic metrics or price system values as compared to non-market economics potential, for understanding resource use.

An important task for resource theory (energy economics) is to develop methods to optimize resource conversion processes. These systems are described and analyzed by means of the methods of mathematics and the natural sciences. Human factors, however, have dominated the development of our perspective of the relationship between nature and society since at least the Industrial Revolution, and in particular, have influenced how we describe and measure the economic impacts of changes in resource quality. A balanced view of these issues requires an understanding of the physical framework in which all human ideas, institutions, and aspirations must operate.

Oil imports by country

Energy returned on energy invested

When oil production first began in the mid-nineteenth century, the largest oil fields recovered fifty barrels of oil for every barrel used in the extraction, transportation, and refining. This ratio is often referred to as the Energy Return on Energy Investment (EROI or EROEI). Currently, between one and five barrels of oil are recovered for each barrel-equivalent of energy used in the recovery process. As the EROEI drops to one, or equivalently the net energy gain falls to zero, the oil production is no longer a net energy source. This happens long before the resource is physically exhausted.

Note that it is important to understand the distinction between a barrel of oil, which is a measure of oil, and a barrel of oil equivalent (BOE), which is a measure of energy. Many sources of energy, such as fission, solar, wind, and coal, are not subject to the same near-term supply restrictions that oil is. Accordingly, even an oil source with an EROEI of 0.5 can be usefully exploited if the energy required to produce that oil comes from a cheap and plentiful energy source. Availability of cheap, but hard to transport, natural gas in some oil fields has led to using natural gas to fuel enhanced oil recovery. Similarly, natural gas in huge amounts is used to power most Athabasca Tar Sands plants. Cheap natural gas has also led to ethanol fuel produced with a net EROEI of less than 1, although figures in this area are controversial because methods to measure EROEI are in debate.

Growth-based economic models

Insofar as economic growth is driven by oil consumption growth, post-peak societies must adapt. M. King Hubbert believed:

Our principal constraints are cultural. During the last two centuries we have known nothing but exponential growth and in parallel we have evolved what amounts to an exponential-growth culture, a culture so heavily dependent upon the continuance of exponential growth for its stability that it is incapable of reckoning with problems of nongrowth.

Some economists describe the problem as uneconomic growth or a false economy. At the political right, Fred Ikle has warned about "conservatives addicted to the Utopia of Perpetual Growth". Brief oil interruptions in 1973 and 1979 markedly slowed – but did not stop – the growth of world GDP.

Between 1950 and 1984, as the Green Revolution transformed agriculture around the globe, world grain production increased by 250%. The energy for the Green Revolution was provided by fossil fuels in the form of fertilizers (natural gas), pesticides (oil), and hydrocarbon fueled irrigation.

David Pimentel, professor of ecology and agriculture at Cornell University, and Mario Giampietro, senior researcher at the National Research Institute on Food and Nutrition (INRAN), place in their study Food, Land, Population and the U.S. Economy the maximum U.S. population for a sustainable economy at 200 million. To achieve a sustainable economy world population will have to be reduced by two-thirds, says the study. Without population reduction, this study predicts an agricultural crisis beginning in 2020, becoming critical c. 2050. The peaking of global oil along with the decline in regional natural gas production may precipitate this agricultural crisis sooner than generally expected. Dale Allen Pfeiffer claims that coming decades could see spiraling food prices without relief and massive starvation on a global level such as never experienced before.

Hubbert peaks

Hubbert Peak vs Oil Production

There is an active debate about most suitable sustainability indicator's use and by adopting a thermodynamic approach through the concept of "exergy" and Hubbert peaks, it is possible to incorporate all into a single measure of resource depletion.The exergy analysis of minerals could constitute a universal and transparent tool for the management of the earth's physical stock.

Hubbert peak can be used as a metric for sustainability and depletion of non-renewable resources. It can be used as reference for many metrics for non-renewable resources such as:

  1. Stagnating supplies
  2. Rising prices
  3. Individual country peaks
  4. Decreasing discoveries
  5. Finding and development costs
  6. Spare capacity
  7. Export capabilities of producing countries
  8. System inertia and timing
  9. Reserves-to-production ratio
  10. Past history of depletion and optimism

Although Hubbert peak theory receives most attention in relation to peak oil production, it has also been applied to other natural resources.

Natural gas

Doug Reynolds predicted in 2005 that the North American peak would occur in 2007. Bentley (p. 189) predicted a world "decline in conventional gas production from about 2020".

Coal

Peak coal is significantly further out than peak oil, but we can observe the example of anthracite in the US, a high grade coal whose production peaked in the 1920s. Anthracite was studied by Hubbert, and matches a curve closely. Pennsylvania's coal production also matches Hubbert's curve closely, but this does not mean that coal in Pennsylvania is exhausted—far from it. If production in Pennsylvania returned at its all-time high, there are reserves for 190 years. Hubbert had recoverable coal reserves worldwide at 2500 × 109 metric tons and peaking around 2150 (depending on usage).

More recent estimates suggest an earlier peak. Coal: Resources and Future Production (PDF 630KB), published on April 5, 2007 by the Energy Watch Group (EWG), which reports to the German Parliament, found that global coal production could peak in as few as 15 years. Reporting on this Richard Heinberg also notes that the date of peak annual energetic extraction from coal will likely come earlier than the date of peak in quantity of coal (tons per year) extracted as the most energy-dense types of coal have been mined most extensively. A second study, The Future of Coal by B. Kavalov and S. D. Peteves of the Institute for Energy (IFE), prepared for European Commission Joint Research Centre, reaches similar conclusions and states that ""coal might not be so abundant, widely available and reliable as an energy source in the future".

Work by David Rutledge of Caltech predicts that the total of world coal production will amount to only about 450 gigatonnes. This implies that coal is running out faster than usually assumed.

Finally, insofar as global peak oil and peak in natural gas are expected anywhere from imminently to within decades at most, any increase in coal production (mining) per annum to compensate for declines in oil or NG production, would necessarily translate to an earlier date of peak as compared with peak coal under a scenario in which annual production remains constant.

Fissionable materials

In a paper in 1956, after a review of US fissionable reserves, Hubbert notes of nuclear power:

There is promise, however, provided mankind can solve its international problems and not destroy itself with nuclear weapons, and provided world population (which is now expanding at such a rate as to double in less than a century) can somehow be brought under control, that we may at last have found an energy supply adequate for our needs for at least the next few centuries of the "foreseeable future."

Technologies such as the thorium fuel cycle, reprocessing and fast breeders can, in theory, considerably extend the life of uranium reserves. Roscoe Bartlett claims 

Our current throwaway nuclear cycle uses up the world reserve of low-cost uranium in about 20 years.

Caltech physics professor David Goodstein has stated that

... you would have to build 10,000 of the largest power plants that are feasible by engineering standards in order to replace the 10 terawatts of fossil fuel we're burning today ... that's a staggering amount and if you did that, the known reserves of uranium would last for 10 to 20 years at that burn rate. So, it's at best a bridging technology ... You can use the rest of the uranium to breed plutonium 239 then we'd have at least 100 times as much fuel to use. But that means you're making plutonium, which is an extremely dangerous thing to do in the dangerous world that we live in.

Metals

Hubbert applied his theory to "rock containing an abnormally high concentration of a given metal" and reasoned that the peak production for metals such as copper, tin, lead, zinc and others would occur in the time frame of decades and iron in the time frame of two centuries like coal. The price of copper rose 500% between 2003 and 2007 was by some attributed to peak copper. Copper prices later fell, along with many other commodities and stock prices, as demand shrank from fear of a global recession. Lithium availability is a concern for a fleet of Li-ion battery using cars but a paper published in 1996 estimated that world reserves are adequate for at least 50 years. A similar prediction for platinum use in fuel cells notes that the metal could be easily recycled.

Phosphorus

Phosphorus supplies are essential to farming and depletion of reserves is estimated at somewhere from 60 to 130 years. Individual countries supplies vary widely; without a recycling initiative America's supply  is estimated around 30 years. Phosphorus supplies affect total agricultural output which in turn limits alternative fuels such as biodiesel and ethanol.

Peak water

Hubbert's original analysis did not apply to renewable resources. However over-exploitation often results in a Hubbert peak nonetheless. A modified Hubbert curve applies to any resource that can be harvested faster than it can be replaced.

For example, a reserve such as the Ogallala Aquifer can be mined at a rate that far exceeds replenishment. This turns much of the world's underground water  and lakes into finite resources with peak usage debates similar to oil. These debates usually center around agriculture and suburban water usage but generation of electricity  from nuclear energy or coal and tar sands mining mentioned above is also water resource intensive. The term fossil water is sometimes used to describe aquifers whose water is not being recharged.

Renewable resources

  • Fisheries: At least one researcher has attempted to perform Hubbert linearization (Hubbert curve) on the whaling industry, as well as charting the transparently dependent price of caviar on sturgeon depletion. Another example is the cod of the North Sea. The comparison of the cases of fisheries and of mineral extraction tells us that the human pressure on the environment is causing a wide range of resources to go through a depletion cycle which follows a Hubbert curve.

Sustainability gaps

Sustainability measurements and indicators is an ever-evolving and changing process and has various gaps to be filled to achieve a proper framework and model. The following are some of the breaks in continuity:

  • Global indicators- Due to difference in social, economical, and environmental conditions of countries, each country has its own indicators and indexes to measure sustainability, which can lead to improper and varying interpretation at the global level. Hence, there should be common indexes and measuring parameters that would allow comparisons among countries. In agriculture, comparable indicators are already in use. Coffee and cocoa studies in twelve countries using common indicators are among the first to report insights from comparing across countries.
  • Policymaking- After the indicators are defined and analysis is done for the measurements from the indicators, proper policymaking methodology can be set up to improve the results achieved. Policymaking would implement changes in the particular inventory list used for measuring, which could lead to better results.
  • Development of individual indicators- Value-based indicators can be developed to measure the efforts by every human being part of the ecosystem. This can affect policymaking, as policy is effective only if there is public participation.
  • Data collection- Due to improper methodology applied to data collection, dynamics of change in data, lack of adequate time and improper framework in analysis of data, can lead to measurements that can be outdated, inaccurate, and unpresentable. Data collections are intended to be from the grass-roots level and there can be proper framework and regulation associated with it. It is intended to have a proper hierarchy of data collection starting from local zones to state level to national level and finally contributing to the global level measurements. Data collected can be made easy to understand so that it could be correctly interpreted and presented through graphs, charts, and analysis bars.
  • Integration across academic disciplines- Sustainability involves whole of the ecosystem and is intended to have a holistic approach. For this purpose measurements intends to involve data and knowledge from all academic backgrounds. Moreover, these disciplines and insights are intended to align with the societal actions.

Silicate mineral

From Wikipedia, the free encyclopedia
 
Copper silicate mineral chrysocolla

Silicate minerals are rock-forming minerals made up of silicate groups. They are the largest and most important class of minerals and make up approximately 90 percent of Earth's crust.

In mineralogy, silica (silicon dioxide) SiO2 is usually considered a silicate mineral. Silica is found in nature as the mineral quartz, and its polymorphs.

On Earth, a wide variety of silicate minerals occur in an even wider range of combinations as a result of the processes that have been forming and re-working the crust for billions of years. These processes include partial melting, crystallization, fractionation, metamorphism, weathering, and diagenesis.

Diatomaceous earth, a biogenic form of silica as viewed under a microscope. The imaged region measures approximately 1.13 by 0.69 mm.

Living organisms also contribute to this geologic cycle. For example, a type of plankton known as diatoms construct their exoskeletons ("frustules") from silica extracted from seawater. The frustules of dead diatoms are a major constituent of deep ocean sediment, and of diatomaceous earth.

General structure

A silicate mineral is generally an ionic compound whose anions consist predominantly of silicon and oxygen atoms.

In most minerals in the Earth's crust, each silicon atom is the center of an ideal silicon–oxygen tetrahedron. Two adjacent tetrahedra may share a vertex, meaning that the oxygen atom is a bridge connecting the two silicon atoms. An unpaired vertex represents an ionized oxygen atom, covalently bound to a single silicon atom, that contributes one unit of negative charge to the anion.

Some silicon centers may be replaced by atoms of other elements, still bound to the four corner oxygen corners. If the substituted atom is not normally tetravalent, it usually contributes extra charge to the anion, which then requires extra cations. For example, in the mineral orthoclase [KAlSi
3
O
8
]
n
, the anion is a tridimensional network of tetrahedra in which all oxygen corners are shared. If all tetrahedra had silicon centers, the anion would be just neutral silica [SiO
2
]
n
. Replacement of one in every four silicon atoms by an aluminum atom results in the anion [AlSi
3
O
8
]
n
, whose charge is neutralized by the potassium cations K+
.

Main groups

In mineralogy, silicate minerals are classified into seven major groups according to the structure of their silicate anion:

Major group Structure Chemical formula Example
Nesosilicates isolated silicon tetrahedra [SiO4]4− olivine, garnet, zircon...
Sorosilicates double tetrahedra [Si2O7]6− epidote, melilite group
Cyclosilicates rings [SinO3n]2n beryl group, tourmaline group
Inosilicates single chain [SinO3n]2n pyroxene group
Inosilicates double chain [Si4nO11n]6n amphibole group
Phyllosilicates sheets [Si2nO5n]2n micas and clays
Tectosilicates 3D framework [AlxSiyO(2x+2y)]x quartz, feldspars, zeolites

Note that tectosilicates can only have additional cations if some of the silicon is replaced by an atom of lower valence such as aluminum. Al for Si substitution is common.

Nesosilicates or orthosilicates

Orthosilicate anion SiO4−
4
. The grey ball represents the silicon atom, and the red balls are the oxygen atoms.
 
Nesosilicate specimens at the Museum of Geology in South Dakota
 

Nesosilicates (from Greek νῆσος nēsos 'island'), or orthosilicates, have the orthosilicate ion, which constitute isolated (insular) [SiO4]4− tetrahedra that are connected only by interstitial cations. The Nickel–Strunz classification is 09.A –examples include:

Kyanite crystals (unknown scale)

Sorosilicates

Pyrosilicate anion Si
2
O6−
7
.
 
Sorosilicate exhibit at Museum of Geology in South Dakota
 

Sorosilicates (from Greek σωρός sōros 'heap, mound') have isolated pyrosilicate anions Si
2
O6−
7
, consisting of double tetrahedra with a shared oxygen vertex—a silicon:oxygen ratio of 2:7. The Nickel–Strunz classification is 09.B. Examples include:

Cyclosilicates

Cyclosilicate specimens at the Museum of Geology, South Dakota
 

Cyclosilicates (from Greek κύκλος kýklos 'circle'), or ring silicates, have three or more tetrahedra linked in a ring. The general formula is (SixO3x)2x, where one or more silicon atoms can be replaced by other 4-coordinated atom(s). The silicon:oxygen ratio is 1:3. Double rings have the formula (Si2xO5x)2x or a 2:5 ratio. The Nickel–Strunz classification is 09.C. Possible ring sizes include:

Some example minerals are:

  • 3-member single ring
  • 4-member single ring
  • 6-member single ring
  • 9-member single ring
    • EudialyteNa
      15
      Ca
      6
      (Fe,Mn)
      3
      Zr
      3
      SiO(O,OH,H
      2
      O)
      3
      (Si
      3
      O
      9
      )
      2
      (Si
      9
      O
      27
      )
      2
      (OH,Cl)
      2
  • 6-member double ring

Note that the ring in axinite contains two B and four Si tetrahedra and is highly distorted compared to the other 6-member ring cyclosilicates.

Inosilicates

Inosilicates (from Greek ἴς is [genitive: ἰνός inos] 'fibre'), or chain silicates, have interlocking chains of silicate tetrahedra with either SiO3, 1:3 ratio, for single chains or Si4O11, 4:11 ratio, for double chains. The Nickel–Strunz classification is 09.D – examples include:

Single chain inosilicates

Double chain inosilicates

Phyllosilicates

Phyllosilicates (from Greek φύλλον phýllon 'leaf'), or sheet silicates, form parallel sheets of silicate tetrahedra with Si2O5 or a 2:5 ratio. The Nickel–Strunz classification is 09.E. All phyllosilicate minerals are hydrated, with either water or hydroxyl groups attached.

Kaolinite

Examples include:

Tectosilicates

Silica family (SiO2 3D network), β-quartz.
 
The 3D aluminosilicate anion of synthetic zeolite ZSM-5.
 
Lunar ferroan anorthosite (plagioclase feldspar) collected by Apollo 16 astronauts from the Lunar Highlands near Descartes Crater

Tectosilicates, or "framework silicates," have a three-dimensional framework of silicate tetrahedra with SiO2 in a 1:2 ratio. This group comprises nearly 75% of the crust of the Earth. Tectosilicates, with the exception of the quartz group, are aluminosilicates. The Nickel–Strunz classifications are 09.F and 09.G, 04.DA (Quartz/ silica family). Examples include:

Inequality (mathematics)

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