Thursday, September 14, 2006

Working & Living in ASEAN: Between Foreign Talent and Immigrant Labour – Perspective of a male Singaporean Citizen who has served National Service.

In the era of globalization, barriers to international employment that were once present have been demolished with every new free trade agreement signed, every trans-national treaty acceded to. In this day and age, most wear the badge of a global citizen with pride. International job mobility is perceived as good, and a refusal to be fluid can leave one stuck with the prospect of unemployment and a higher standard of living.

The first speech Dr. Jorgen O. Moller clearly supports the above stance. He particularly raises the example of world-renowned football clubs having a team of international players to support this point. While I am not entirely against what he states in entirety, as I do believe organizations do have the right to seek the best from around so as to meet their operating targets. However, sometimes, probably also due to government encouragement and policy, organizations might be all-too-eager to recruit international talents that they overlook the potential that the local talent pool holds. While international expertise adds the diversity of overseas management experience into the organizational mix, but should an organization be overzealous in its pursuit in the collection of international perspectives in its senior management, it may lose focus on what made it successful in the first place – an innate understanding and awareness of the local ground and needs; which is what the local employees whom has worked their way from ground up possess. Multinational corporations and companies aspiring to go global should never forget that to be successful in business, competency in local market knowledge is often more important than a plethora of diverse opinions from expatriates which might or might not work, due to the differences in cultures.

The second presentation given by Ms Mathi addressed more on the issues of the welfare and well-being of foreign labour in this country. I am in general support of her opinions and views that most of our lower wage earning workers should be treated with more respect and given more welfare, given that they do work that most Singaporeans are unwilling to do, and if we had a less liberal foreign labour policy, chances are that most Singaporean families would be unable to afford a foreign helper at home, or have such well-maintained infrastructure and clean surrounding environments. However, it must be noted that due to the drop in real income of our bottom 30% of families, many Singaporeans have also taken up jobs that are on level with the foreign labour that is employed here. While we should show care and concern to the low-wage foreign workers in Singapore, let us not forget about the low-income families here in Singapore as well, and provide them with equivalent or better welfare to that of the low-wage foreign workers, given that they are our brethrens after all.

I didn’t manage to catch the gist of Mr David Ang’s speech as I was in the washroom for the first half of his speech, and hence I cannot comment on his speech.

In summary, I am all for the need for further economic integration and labour integration of ASEAN. However, let us please do not forget about our own less well-off citizens while society busies itself with the above activities.

Monday, September 11, 2006

Peak Oil vs. Running Out of Oil

Will Singapore Survive Post-Peak Oil? Considering we import almost all our food...I highly doubt it...Thailand & Vietnam are better places to live in should the Peak pass...

Extracted from The Oil Drum -
DrumBeat: September 11, 2006.

...Many people in the Peak Oil movement claims that we are running out of oil. While there may be many very uninformed nuts out there who really believe we are running out of oil, they, by definition, could not possibly be peak oilers. It would be impossible to be at peak production and out of oil, that is just plain common sense. All peak oilers know that post peak, the amount of oil available each year will decrease each year...forever. Now I know there may be one year or two when oil the oil supply will increase, just as the US production increased for a few years after Prudhoe Bay came on line. But the trend will be downward....forever or until not enough oil is produced to even measure.

What many seem to think is that returning to 1980 oil production levels will mean a 1980 lifestyle. That is, if we will just have to scale back a little and, with the aid of ethanol and biodiesel we will get by just fine. This is what most of us peak oilers deny.

First of all, the decline is not likely to be steady. Most oil exporters will have dramatically increased their domestic production. They will supply their own needs before trying to keep the rest of the world on an even keel. There will develop an enormous difference between the oil available in countries that now export oil and countries that now must import most of their oil.

Second, most of these countries, who now realize the gravity of the situation, will start to husband their oil. They will cut back on production in order to insure stability in their own countries at the expense of the rest of the world.

Third, the realization will eventually dawn on the world's markets that all the economies of the world must now shrink instead of grow. Capitalism depends on growth. People invest for growth and no one invests for shrinkage. People will pull their money out of the market because they will correctly see the crash coming. This will just exacerbate the situation and we will have a disastrous world-wide market crash. This will mean lay-offs, unemployment, and an economic disaster far surpassing anything seen in the great depression.

The world's population will have at least doubled since 1980. And since we are already seeing a drop in grain and other food production, this will greatly exacerbate the problem. Dropping oil production will mean that grain and other food production will begin to drop like a rock. There will be food riots all over the world.

And as some have already pointed out, the oil left will be prioritized. That is the military will be first in line, then what is deemed "necessary government agencies" and so on down the line.

And that is the point Roger, and others who seem to think that declining oil production will simply mean a slightly lower lifestyle. Not even close. No, the world as we know it feeds on oil. And as the oil flow is interrupted, and gets a little worse every year, then civilization as we know it will disappear a little each year. Anarchy and resource wars will probably accelerate the situation until the scenario pictured by David Price comes to pass...

David Price's Die-off Scenario. We'll crash just like a bacteria colony on an agar plate after blooming beyond the carrying capacity of the agar dish:


Operative mechanisms in the collapse of the human population will be starvation, social strife, and disease. These major disasters were recognized long before Malthus and have been represented in western culture as horsemen of the apocalypse. 8 They are all consequences of scarce resources and dense population.

Starvation will be a direct outcome of the depletion of energy resources. Today's dense population is dependent for its food supply on mechanized agriculture and efficient transportation. Energy is used to manufacture and operate farm equipment, and energy is used to take food to market. As less efficient energy resources come to be used, food will grow more expensive and the circle of privileged consumers to whom an adequate supply is available will continue to shrink.

Social strife is another consequence of the rising cost of commercial energy. Everything people want takes energy to produce, and as energy becomes more expensive, fewer people have access to goods they desire. When goods are plentiful, and particularly when per-capita access to goods is increasing, social tensions are muted: Ethnically diverse populations often find it expedient to live harmoniously, governments may be ineffective and slow to respond, and little force is needed to maintain domestic tranquillity. But when goods become scarce, and especially when per-capita access to goods is decreasing, ethnic tensions surface, governments become authoritarian, and goods are acquired, increasingly, by criminal means.

A shortage of resources also cripples public health systems, while a dense population encourages the spread of contagious diseases. Throughout human history, the development of large, dense populations has led to the appearance of contagious diseases that evolved to exploit them. Smallpox and measles were apparently unknown until the second and third centuries AD, when they devastated the population of the Mediterranean basin (McNeill, 1976, p. 105). In the fourteenth century, a yet larger and denser population in both Europe and China provided a hospitable niche for the Black Death. Today, with extremely dense population and all parts of the world linked by air travel, new diseases such as AIDS spread rapidly-and a virus as deadly as AIDS but more easily transmissible could appear at any time.

Starvation, social strife, and disease interact in complex ways. If famine were the sole mechanism of collapse, the species might become extinct quite suddenly. A population that grows in response to abundant but finite resources, like the reindeer of St. Matthew Island, tends to exhaust these resources completely. By the time individuals discover that remaining resources will not be adequate for the next generation, the next generation has already been born. And in its struggle to survive, the last generation uses up every scrap, so that nothing remains that would sustain even a small population. But famine seldom acts alone. It is exacerbated by social strife, which interferes with the production and delivery of food. And it weakens the natural defenses by which organisms fight off disease.

Paradoxically, disease can act to spare resources. If, for example, a new epidemic should reduce the human population to a small number of people who happen to be resistant to it before all the world's resources are severely depleted, the species might be able to survive a while longer.


But even if a few people manage to survive worldwide population collapse, civilization will not. The complex association of cultural traits of which modern humans are so proud is a consequence of abundant resources, and cannot long outlive their depletion.

Civilization refers, in its derivation, to the habit of living in dense nucleated settlements, which appeared as population grew in response to plentiful resources. Many things seem to follow as a matter of course when people live in cities, and wherever civilization occurred, it has involved political consolidation, economic specialization, social stratification, some sort of monumental architecture, and a flowering of artistic and intellectual endeavor (Childe, 1951).

Localized episodes of such cultural elaboration have always been associated with rapid population growth. Reasons for the abundance of resources that promoted this growth vary from one case to another. In some instances, a population moved into a new region with previously untapped resources; in other instances the development or adoption of new crops, new technologies, or new social strategies enhanced production. But the Sumerians, the Greeks, the Romans, the Mayas, and even the Easter Islanders all experienced a surge of creative activity as their populations grew rapidly.

And in all cases, this creative phase, nourished by the same abundance that promoted population growth, came to an end when growth ended. One need not seek esoteric reasons for the decline of Greece or the fall of Rome; in both cases, the growth of population exhausted the resources that had promoted it. After the Golden Age, the population of Greece declined continually for more than a thousand years, from 3 million to about 800,000. The population of the Roman Empire fell from 45 or 46 million, at its height, to about 39 million by 600 AD, and the European part of the empire was reduced by 25% (McEvedy & Jones, 1978).

Even if world population could be held constant, in balance with "renewable" resources, the creative impulse that has been responsible for human achievements during the period of growth would come to an end. And the spiraling collapse that is far more likely will leave, at best, a handfull of survivors. These people might get by, for a while, by picking through the wreckage of civilization, but soon they would have to lead simpler lives, like the hunters and subsistence farmers of the past. They would not have the resources to build great public works or carry forward scientific inquiry. They could not let individuals remain unproductive as they wrote novels or composed symphonies. After a few generations, they might come to believe that the rubble amid which they live is the remains of cities built by gods.

Or it may prove impossible for even a few survivors to subsist on the meager resources left in civilization's wake. The children of the highly technological society into which more and more of the world's peoples are being drawn will not know how to support themselves by hunting and gathering or by simple agriculture. In addition, the wealth of wild animals that once sustained hunting societies will be gone, and topsoil that has been spoiled by tractors will yield poorly to the hoe. A species that has come to depend on complex technologies to mediate its relationship with the environment may not long survive their loss.


For Malthus, the imbalance between the growth of population and means of subsistence might be corrected, from time to time, through natural disasters, but the human species could, in principle, survive indefinitely. Malthus did not know that the universe is governed by the Second Law of Thermodynamics; he did not understand the population dynamics of introduced species; and he did not appreciate that humans, having evolved long after the resource base on which they now rely, are effectively an introduced species on their own planet.

The short tenure of the human species marks a turning point in the history of life on Earth. Before the appearance of Homo sapiens, energy was being sequestered more rapidly than it was being dissipated. Then human beings evolved, with the capacity to dissipate much of the energy that had been sequestered, partially redressing the planet's energy balance. The evolution of a species like Homo sapiens may be an integral part of the life process, anywhere in the universe it happens to occur. As life develops, autotrophs expand and make a place for heterotrophs. If organic energy is sequestered in substantial reserves, as geological processes are bound to do, then the appearance of a species that can release it is all but assured. Such a species, evolved in the service of entropy, quickly returns its planet to a lower energy level. In an evolutionary instant, it explodes and is gone.

If the passage of Homo sapiens across evolution's stage significantly alters Earth's atmosphere, virtually all living things may become extinct quite rapidly. But even if this does not happen, the rise and fall of Homo sapiens will eliminate many species. It has been estimated that they are going extinct at a rate of 17,500 per year (Wilson, 1988, p. 13), and in the next twenty-five years as many as one-quarter of the world's species may be lost (Raven, 1988, p. 121).

This is a radical reduction in biological diversity, although life has survived other die-offs, such as the great collapse at the end of the Permian. It is unlikely, however, that anything quite like human beings will come this way again. The resources that have made humans what they are will be gone, and there may not be time before the sun burns out for new deposits of fossil fuel to form and intelligent new scavengers to evolve. The universe seems to have had a unique beginning, some ten or twenty billion years ago (Hawking, 1988, p. 108). Since that time, a star had to live and die to provide the materials for the solar system -- which, itself, is several billion years old. Perhaps life could not have happened any sooner than it did. Perhaps Homo sapiens could not have evolved any sooner. Or later. Perhaps everything has its season, a window of opportunity that opens for a while, then shuts.

Sunday, September 10, 2006

Green House Gases, Global Warming & Climate Change

Climate change

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Variations in CO2, temperature and dust from the Vostok ice core over the last 400 000 years
Variations in CO2, temperature and dust from the Vostok ice core over the last 400 000 years

Climate change refers to the variation in the Earth's global climate or in regional climates over time. It describes changes in the variability or average state of the atmosphere—or average weather—over time scales ranging from decades to millions of years. These changes may come from processes internal to the Earth, be driven by external forces (e.g. variations in sunlight intensity) or, most recently, be caused by human activities.

In recent usage, especially in the context of environmental policy, the term "climate change" often refers only to the ongoing changes in modern climate, including the rise in average surface temperature known as global warming. In some cases, the term is also used with a presumption of human causation, as in the United Nations Framework Convention on Climate Change (UNFCCC). The UNFCCC uses "climate variability" for non-human caused variations.[1]

For information on temperature measurements over various periods, and the data sources available, see temperature record. For attribution of climate change over the past century, see attribution of recent climate change.

Climate change factors

Climate changes reflect variations within the Earth's environment, natural processes going on around it, and the impact of human activity. The external factors which can shape climate are often called climate forcings and include such processes as variations in solar radiation, the Earth's orbit, and greenhouse gas concentrations.

Variations within the Earth's climate

Weather, in and of itself, is a chaotic non-linear dynamical system, but in many cases, it is observed that the climate (i.e., the average state of weather) is fairly stable and predictable. This includes the average temperature, amount of precipitation, days of sunlight, and many other variables that might be measured at any given site. However, there are also changes within the Earth's environment that can affect the climate.


Percentage of advancing glaciers in the Alps in the last 80 years
Percentage of advancing glaciers in the Alps in the last 80 years

Glaciers are recognized as one of the most sensitive indicators of climate change, advancing substantially during climate cooling (e.g., the Little Ice Age of the last century) and retreating during climate warming on moderate time scales. Glaciers grow and collapse, both contributing to natural variability and greatly amplifying external forces. For the last century, however, glaciers have been unable to regenerate enough ice during the winters to make up for the ice lost during the summer months (see glacier retreat for more).

The most important climate processes of the last several million years are the glacial and interglacial cycles of the present ice age. Though shaped by orbital variations, the internal responses involving continental ice sheets and 130 m sea-level change certainly played a key role in deciding what climate response would be observed in most regions. Other changes, including Heinrich events, Dansgaard–Oeschger events and the Younger Dryas show the potential for glacial variations to influence climate even in the absence of specific orbital changes.

Ocean variability

A schematic of modern thermohaline circulation
A schematic of modern thermohaline circulation

On the scale of mere decades, climate changes can also result from changes within the ocean/atmosphere systems. Many climate states, most obviously El Niño Southern oscillation, but also including the Pacific decadal oscillation, the North Atlantic oscillation, and the Arctic oscillation, have been recognized as modes within the climate system, owing their existence at least in part to different ways that heat can be stored in the oceans and move between different reservoirs. On longer time scales, ocean processes such as thermohaline circulation play a key role in redistributing heat, and could, if changed, dramatically impact climate.

The memory of climate

More generally, most forms of internal variability in the climate system can be recognized as a form of hysteresis, meaning that the current state of climate reflects not only the inputs, but also the history of how it got there. For example, a decade of dry conditions may cause lakes to shrink, plains to dry up and deserts to expand. In turn, these conditions may lead to less rainfall in the following years. In short, climate change can be a self-perpetuating process because different aspects of the environment respond at different rates and in different ways to the fluctuations that inevitably occur.

Non-climate factors driving climate change

Greenhouse gases

Carbon dioxide variations during the last 500 million years
Carbon dioxide variations during the last 500 million years

Current studies indicate that radiative forcing by greenhouse gases is the primary cause of global warming. Greenhouse gases are also important in understanding Earth's climate history. According to these studies, the greenhouse effect, which is the warming produced as greenhouse gases trap heat, plays a key role in regulating Earth's temperature.

Over the last 600 million years, carbon dioxide concentrations have varied from perhaps >5000 ppm to less than 200 ppm, due primarily to the impact of geological processes and biological innovations. Curiously, it has been argued (Veizer et al. 1999) that variations in greenhouse gas concentrations over tens of millions of years have not been well correlated to climate change, with plate tectonics perhaps playing a more dominant role. However there are several examples of rapid changes in the concentrations of greenhouse gases in the Earth's atmosphere that do appear to correlate to strong warming, including the Paleocene–Eocene thermal maximum, the Permian–Triassic extinction event, and the end of the Varangian snowball earth event.

During the modern era, rising carbon dioxide levels are implicated as the primary cause to global warming since 1950.

Plate tectonics

On the longest time scales, plate tectonics will reposition continents, shape oceans, build and tear down mountains and generally serve to define the stage upon which climate exists. More recently, plate motions have been implicated in the intensification of the present ice age when, approximately 3 million years ago, the North and South American plates collided to form the Isthmus of Panama and shut off direct mixing between the Atlantic and Pacific Oceans.

Solar variation

Variations in solar activity during the last several centuries based on observations of sunspots and beryllium isotopes.
Variations in solar activity during the last several centuries based on observations of sunspots and beryllium isotopes.

The sun, as the ultimate source of nearly all energy in the climate system, is an integral part of shaping Earth's climate. On the longest time scales, the sun itself is getting brighter as it continues its main sequence evolution. Early in Earth's history, it is thought to have been too cold to support liquid water at the Earth's surface, leading to what is known as the Faint young sun paradox.

On more modern time scales, there are also a variety of forms of solar variation, including the 11–year solar cycle and longer-term modulations. However, the 11–year sunspot cycle does not manifest itself clearly in the climatological data. These variations are considered to be influential in triggering the Little Ice Age and for some of the warming observed from 1900 to 1950.

Orbital variations

In their impact on climate, orbital variations are in some sense an extension of solar variability, because slight variations in the Earth's orbit lead to changes in the distribution and abundance of sunlight reaching the Earth's surface. Such orbital variations, known as Milankovitch cycles, are a highly predictable consequence of basic physics due to the mutual interactions of the Earth, its moon, and the other planets. These variations are considered the driving factors underlying the glacial and interglacial cycles of the present ice age. Subtler variations are also present, such as the repeated advance and retreat of the Sahara desert in response to orbital precession.


A single eruption of the kind that occurs several times per century can impact climate, causing cooling for a period of a few years. For example, the eruption of Mount Pinatubo in 1991 is barely visible on the global temperature profile. Huge eruptions, known as large igneous provinces, occur only a few times every hundred million years, but can reshape climate for millions of years and cause mass extinctions.

Human influences

Anthropogenic factors are acts by humans that change the environment and influence climate. The biggest factor of present concern is the increase in CO2 levels due to emissions from fossil fuel combustion, followed by aerosols (particulate matter in the atmosphere) which exerts a cooling effect. Other factors, including land use, ozone depletion, and deforestation also impact climate.

Fossil fuels

Carbon dioxide variations over the last 400,000 years, showing a rise since the industrial revolution.
Carbon dioxide variations over the last 400,000 years, showing a rise since the industrial revolution.

Beginning with the industrial revolution in the 1850s and accelerating ever since, the human consumption of fossil fuels has elevated CO2 levels from a concentration of ~280 ppm to more than 370 ppm today. These increases are projected to reach more than 560 ppm before the end of the 21st century. Along with rising methane levels, these changes are anticipated to cause an increase of 1.4–5.6 °C between 1990 and 2100. (reference needed)


Anthropogenic aerosols, particularly sulphate aerosols from fossil fuel combustion, are believed to exert a cooling influence; see graph.[2] This, together with natural variability, is believed to account for the relative "plateau" in the graph of 20th century temperatures in the middle of the century.

Land use

Prior to widespread fossil fuel use, humanity's largest impact on local climate is likely to have resulted from land use. Irrigation, deforestation, and agriculture fundamentally change the environment. For example, they change the amount of water going into and out of a given locale. They also may change the local albedo by influencing the ground cover and altering the amount of sunlight which is absorbed. For example, there is evidence to suggest that the climate of Greece and other Mediterranean countries was permanently changed by widespread deforestation between 700 BC and 0 BC (the wood being used for ship-building, construction and fuel purposes), with the result that the modern climate in the region is significantly hotter and drier and the species of trees which were used for ship-building in the ancient world can no longer be found in the area.

A controversial hypothesis by William Ruddiman suggests that the rise of agriculture and the accompanying deforestation led to the increases in carbon dioxide and methane during the period 5000–8000 years ago. These increases, which reversed previous declines, may have been responsible for delaying the onset of the next glacial period, according to Ruddimann's hypothesis.

Interplay of factors

If a certain forcing (for example, solar variation) acts to change the climate, then there may be mechanisms which act to amplify or reduce the effects. These are called positive and negative feedbacks. As far as is known, the climate system is generally stable with respect to these feedbacks: positive feedbacks do not "run away". Part of the reason for this is the existence of a powerful negative feedback between temperature and emitted radiation: radiation increases as the fourth power of absolute temperature.

However, a number of important positive feedbacks do exist. The glacial and interglacial cycles of the present ice age provide an important example. It is believed that orbital variations provide the timing for the growth and retreat of ice sheets. However, the ice sheets themselves reflect sunlight back into space and hence promote cooling and their own growth, known as the ice–albedo feedback. Further, falling sea levels and expanding ice decrease plant growth and indirectly lead to declines in carbon dioxide and methane. This leads to further cooling.

Similarly, rising temperatures caused, for example, by anthropogenic emissions of greenhouse gases could lead to retreating snow lines, revealing darker ground underneath, and consequently result in more absorption of sunlight.

Water vapor, methane, and carbon dioxide can also act as significant positive feedbacks, their levels rising in response to a warming trend, thereby accelerating that trend. Water vapor acts strictly as a feedback (excepting small amounts in the stratosphere), unlike the other major greenhouse gases, which can also act as forcings.

More complex feedbacks involve the possibility of changing circulation patterns in the ocean or atmosphere. For example, a significant concern in the modern case is that melting glacial ice from Greenland will interfere with sinking waters in the North Atlantic and inhibit thermohaline circulation. This could affect the Gulf Stream and the distribution of heat to Europe and the east coast of the United States.

Other potential feedbacks are not well understood and may either inhibit or promote warming. For example, it is unclear whether rising temperatures promote or inhibit vegetative growth, which could in turn draw down either more or less carbon dioxide. Similarly, increasing temperatures may lead to either more or less cloud cover.[3] Since on balance cloud cover has a strong cooling effect, any change to the abundance of clouds also impacts climate.[4]

Monitoring the current status of climate

Scientists use "Indicator time series" that represent the many aspects of climate and ecosystem status. The time history provides an historical context. Current status of the climate is also monitored with climate indices.[5][6][7]

Evidence for Climatic Change

Evidence for climatic change is taken from a variety of sources which can be used to reconstruct past climates. Most of the evidence is indirect—climatic changes are inferred from changes in indicators that reflect climate, such as vegetation, Dendrochronology, Ice cores, sea level change, glacial retreat.

Pollen Analysis

Species have particular climatic requirements which influence their geographical distributions. Each plant species has a distinctively shaped pollen grain and if these fall into oxygen-free environments, such as peat bogs, they resist decay. Changes in the pollen found in different levels of the bog indicate, by implication, changes in climate.

One limitation of this method is the fact that pollen can be transported considerable distances by wind or sometimes by wildlife.


Remains of Coleoptera beetles are common in freshwater and land sediments. Different species of this beetle tend to be found under different climatic conditions. Knowledge of the present climatic range of the different species, and the age of the sediments in which remains are found, allows past climatic conditions to be worked out.

Glacial Geology

Advancing glaciers leave behind moraines and other features which often have datable material in them, recording the time when a glacier advance and deposited a feature. Similarly the lack of glacier cover can be identified by the presence of datable soil or volcanic tephra horizons. Glaciers are considered one of the most sensitive climate indicators by the IPCC, and their recent observed variations provide a global signal of climate change, see Retreat of glaciers since 1850.

Historical Records

Historical records include cave paintings, depth of grave digging in Greenland, diaries, documentary evidence of events (such as 'frost fairs' on the Thames) and evidence of areas of vine cultivation. Since 1873 daily weather reports have been documented, and the Royal Society has encouraged the collection of data since the seventeenth century. Parish records are often a good source of climate data.

Examples of climate change

Climate change has continued throughout the entire history of Earth. The field of paleoclimatology has provided information of climate change in the ancient past, supplementing modern observations of climate. Obviously, most of these prehistoric changes are solely the result of natural factors.

  1. Climate of the deep past
  2. Climate of the last 500 million years
  3. Climate of recent glaciations
  4. Recent climate

See also


  1. ^
  2. ^ IPCC TAR SPM figure 3
  3. ^
  4. ^ For additional discussion of feedbacks relevant to ongoing climate change, see
  5. ^ Arctic Change Indicators
  6. ^ Bering Sea Climate and Ecosystem Indicators
  7. ^ How scientists study climate change: Some important research concepts used by scientists to study climate variations
  • Increasing destructiveness of tropical cyclones over the past 30 years. K.A. Emanuel, Nature, 436 (2005), pp. 686-688.
  • What effects are we seeing now and what is still to come? Calvin Jones "Climate Change: Facts and Impacts"
  • Changing the Atmosphere: Expert Knowledge and Environmental Governance (Politics, Science & the Environment (Paperback)), edited by Clark Miller and Paul N. Edwards, MIT Press 2001
  • The anthropogenic greenhouse era began thousands of years ago, Ruddiman WF; Climatic Change, 61 (3): 261-293 Dec 2003
  • William F. Ruddiman (2005), Plows, Plagues, and Petroleum: How Humans Took Control of Climate, Princeton University Press
  • A test of the overdue-glaciation hypothesis, William F. Ruddiman, Stephen J. Vavrus, John E. Kutzbach, Quaternary Science Reviews 24 (2005) 1­1
  • A note on the relationship between ice core methane concentrations and insolation, Schmidt, GA, Shindel, DT and Harder, S; GRL v31 L23206, 16 December 2004.

External links

BBC articles

Marion King Hubbert's Peak Oil Theory

Hubbert peak theory

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A bell-shaped production curve, as suggested by M. King Hubbert in 1956.
A bell-shaped production curve, as suggested by M. King Hubbert in 1956.
2004 U.S. government predictions for oil production other than in OPEC and the former Soviet Union
2004 U.S. government predictions for oil production other than in OPEC and the former Soviet Union

The Hubbert Peak theory posits that for any given geographical area, from an individual oil field to the planet as a whole, the rate of oil production tends to follow a bell-shaped curve. Early in the curve (pre-peak), production increases due to the addition of infrastructure. Late in the curve (post-peak), production declines due to resource depletion.

"Peak Oil" as a proper noun, also known as Hubbert's peak, refers to a singular event in history: the peak of the entire planet's oil production. After Peak Oil, according to the Hubbert Peak Theory, the rate of oil production on Earth will enter a terminal decline. The theory is named after American geophysicist Marion King Hubbert, who created a model of known oil reserves, and proposed, in a paper he presented to the American Petroleum Institute in 1956 [3], that production of oil from conventional sources would peak in the continental United States between 1965 and 1970, and worldwide within "about half a century" from publication.

When the global peak will occur is a controversial issue. Production peaks are difficult to predict, and generally the only reliable way to identify the timing of any production peak, including the global peak, is in retrospect. United States oil production peaked in 1971 [4]. The peak of world oilfield discoveries occurred in 1962 [5]. Some estimates for the date of worldwide peak in oil production, made by Hubbert and others, have already passed. Estimates for the date of Peak Oil range from 2005 to dates after 2025.

Some industrialized countries are currently highly dependent on oil. Opinions on the effects of Hubbert's peak, and the subsequent terminal decline of global oil production, range from predictions that the market economy will develop alternatives to oil and decrease oil dependence in modern economies, to doomsday scenarios of global economic meltdown and societal collapse.

Hubbert's theory

The standard Hubbert curve.  For applications, the x and y scales are replaced by time and production scales.
The standard Hubbert curve. For applications, the x and y scales are replaced by time and production scales.
A clear example of hubbert theory applying on Norway's production‎
A clear example of hubbert theory applying on Norway's production‎

In 1956, Hubbert proposed that crude oil production in a given region over time would follow a bell-shaped curve without giving a precise formula; he later used the Hubbert curve, the derivative of the logistic curve, for estimating future production.

Hubbert assumed that after oil reserves are discovered, oil production at first increases approximately exponentially, as wells are drilled and more efficient facilities are installed. At some point, a peak output is reached, and oil production begins declining until it approximates an exponential decline.

The Hubbert curve satisfies these constraints. Furthermore, it is symmetrical, with the peak of production reached when half of the oil that will ultimately be produced has been. It also has a single peak.

Given past oil production data, a Hubbert curve may be constructed that attempts to approximate past data, and used to provide estimates for future production. In particular, the date of peak oil production and the total amount of oil ultimately produced can be estimated that way.

The standard Hubbert curve is a real-valued function of one real variable; in order to apply it to the real world, scales have to be chosen, one for time and one for oil production, based on the observed data. They are usually given implicitly by specifying the integral of the Hubbert curve, the ultimate total oil production Q, with a unit of billions of barrels, and the initial growth rate asymptotically reached for very early times, a, often expressed in percent per year.

Hubbert also proposed a method for determining the values for Q and a based on empirical data, by considering the ratio of production at a given time and cumulative production to that point as a function not of time but of the cumulative production itself; if production followed a Hubbert curve, this function would have the form a - \frac{Q}{Q_\infty} a, a straight line. Thus, by considering the best linear fit to the function actually observed, estimates for a and Q can be obtained.

Use of multiples curves

, the use of multiple curves instead of one can better model the behavior of diverse systems. In US oil production, Hubbert dealt with a large sampleset that wasn't very politically constrained. How discovery of new resources should be added to a Hubbert curve, and whether they were accounted for in the first place, is always controvertial, but it's intuitively warranted in certain circumstances. Timber production by European powers, for example, would follow its own curves for most of history, followed by the addition of new curves as colonialism took off. [6]

Peak prediction

In 2004, ASPO predicted that conventional plus unconventional oil production would peak around 2007.
In 2004, ASPO predicted that conventional plus unconventional oil production would peak around 2007.
The Energy Information Administration predicts no peak in consumption before at least 2025. Source: International Energy Outlook 2004. The International Energy Agency makes a similar projection
The Energy Information Administration predicts no peak in consumption before at least 2025. Source: International Energy Outlook 2004. The International Energy Agency makes a similar projection

In 1974, Hubbert projected that global oil production would peak in 1995 "if current trends continue" [7] (i.e., 2% growth in consumption per year)[8]. However, in the late 1970s and early 1980s, global oil consumption actually dropped (due to the shift to energy efficient cars, the shift to electricity and natural gas for heating, etc), then rebounded to a lower level of growth in the mid 1980s (see graphics on right). The shift to reduced consumption in these areas meant that the projection assumptions were not realized and, hence, oil production did not peak in 1995.

The Association for the Study of Peak Oil and Gas (ASPO) has calculated that the annual production peak of conventional crude oil was in early 2004. During 2004, approximately 24 billion barrels of conventional oil was produced out of the total of 30 billion barrels of oil; the remaining 6 billion barrels coming from heavy oil and tar sands, deep water oil fields, and natural gas liquids (see adjacent ASPO graph). In 2005, the ASPO revised its prediction for the peak in world oil production, from both conventional and nonconventional sources, to the year 2010[9]. Natural gas is expected to peak anywhere from 2010 to 2020 (Bentley, 2002).

In 2004, 30 billion barrels of oil were consumed worldwide, while only eight billion barrels of new oil reserves were discovered. Huge, easily exploitable oil fields are most likely a thing of the past. In August 2005, the International Energy Agency reported annual global demand at 84.9 million barrels per day (mbd) which means over 31 billion barrels annually. This means consumption is now within 2 mbd of production. At any one time there are about 54 days of stock in the OECD system plus 37 days in emergency stockpiles.

The United States Geological Survey claimed at one time that there are enough petroleum reserves to continue current production rates for 50 to 100 years[10]. That is countered by an important Saudi oil industry insider who says the American government's forecast for future oil supply is a "dangerous over-estimate."[11] Campbell argues that the USGS estimates are methodologically flawed (although he does not claim to be an expert in probability theory)[12]. One problem, for example, is that OPEC countries overestimate their reserves to get higher oil quotas and to avoid internal critique. Population and economic growth will almost certainly lead to increased energy consumption in the future.

According to the Energy Information Administration of the United States Department of Energy, "adjustments to the USGS and MMS estimates are based on non-technical considerations that support domestic supply growth to the levels necessary to meet projected demand levels. [emphasis added]" (Annual Energy Outlook 1998 With Projections to 2020[13]). [This is misquoted; the quoted part is not preceded by "international reserve", and does not make a statement about international reserve estimates.]

Professor Kenneth Deffeyes, author of "Hubbert's Peak" (ISBN 0-691-11625-3) and "Beyond Oil" (ISBN 0-8090-2956-1), asserts that the peak was passed on Dec 16, 2005 [14]. He also asserts that the total of world oil is 2.013 trillion barrels.

Has it happened already?

World oil supply.[2] Source: IEA
World oil supply.[2] Source: IEA
World Oil Supply 2002-2006 Q2. Source: Multiple tables from IEA
World Oil Supply 2002-2006 Q2. Source: Multiple tables from IEA
World Crude Oil Production 1960-2004. Sources:  DOE/EIA, IEA
World Crude Oil Production 1960-2004. Sources: DOE/EIA, IEA

Chevron states that "oil production is in decline in 33 of the 48 largest oil producing countries". [15] Other countries have also passed their individual oil production peaks.

World oil production growth trends, in the short term, have been decreasing over the last 18 months. Average yearly gains in world oil production from 1987 to 2005 were 1.2MB/day (1.7%). Global production averaged 84.4 MB/day in 2005, up only 0.2 MB/day (0.2%) from 84.2MB/day in Q4 2004 (see figure at right). Production in Q2 2006 was 85.1MB/day, up 0.4MB/day (0.47%) from the same period a year earlier [16]. Yearly gains in the last 8 years ranged from -1.4MB/day (-1.9%; 1998-1999) to 3.3MB/day (4.1%; 2003-2004)[17].

Colin Campbell of the Association for the Study of Peak Oil & Gas (ASPO) has suggested that the global production of conventional oil peaked in the spring of 2004 albeit at a rate of 23-GB/yr, not Hubbert's 13-GB/yr. Another peak oil proponent Kenneth S. Deffeyes predicted in his book Beyond Oil - The View From Hubbert's Peak that global oil production would hit a peak on Thanksgiving Day 2005 (Deffeyes has since revised his claim, and now argues that world oil production peaked on December 16 2005[18]). Texas oilman T. Boone Pickens has stated that worldwide conventional oil production will top out at 85MB/day.[19]

Of the three largest oil fields in the world, two have peaked. Mexico announced that its giant Cantarell Field entered depletion in March, 2006, as did the huge Burgan field in Kuwait in November, 2005. Due to past overproduction, Cantarell is now declining rapidly, at a rate of -13% year over year. [20] In April, 2006, a Saudi Aramco spokesman admitted that its mature fields are now declining at a rate of 8% per year, and its composite decline rate of producing fields is about 2%[21], thus implying that Ghawar, the largest oil field in the world may have peaked.

Chevron has launched the Will You Join Us? [22] campaign, seeking to alert the public to the possibility of petroleum depletion and encourage discussion. The campaign's website notes findings from the International Energy Agency's (IEA) World Energy Outlook 2004: "Fossil fuels currently supply most of the world’s energy, and are expected to continue to do so for the foreseeable future. While supplies are currently abundant, they won’t last forever."

Traditional natural gas supplies are also under the constraints of production peaks, which especially affect specific geographic regions because of the difficulty of transporting the resource over long distances. Natural gas production may have peaked on the North American continent in 2003, with the possible exception of Alaskan gas supplies which cannot be developed until a pipeline is constructed. Natural gas production in the North Sea has also peaked. UK production was at its highest point in 2000, and declining production and increased prices are now a sensitive political issue there. Even if new extraction techniques yield additional sources of natural gas, like coalbed methane, the energy returned on energy invested will be much lower than traditional gas sources, which inevitably leads to higher costs to consumers of natural gas.


Peak Oil on a license plate of a hybrid car driving past a wind turbine
Peak Oil on a license plate of a hybrid car driving past a wind turbine

Mitigation efforts attempt to prevent hazards from developing into disasters altogether, or to reduce the effects of disasters when they occur.

Most oil consumption comes from transportation, 68% in America [23], and there are many forms of transportation that do not require oil or require much less than the standard automobile. Today, these include the application of biofuels, high mpg hybrid vehicles, battery electric vehicles and plug-in hybrid electric vehicles. Solar- or hydrogen- powered demonstration vehicles have also been designed and developed as pilot projects or for engineering school competition. Because America uses 1 in 4 barrels of global oil consumed [24] [25] and uses 68% for transportation, it uses 17% of global oil consumption for transportation and is potentially the largest market for any new type of vehicle.

More comprehensive mitigations include better land use planning through Smart growth to reduce transportation inducements, increased capacity and use of mass transit, vanpooling and carpooling, and human powered transport from current levels [26]. Rationing is also a form of mitigation - see [27] for driving ban schemes and a list of policies and their oil savings in table E-1.

Since mitigation affects the price of oil and the economy it is very important in calculating the timing and shape of a peak. Conversely the shape of the peak[1] affects mitigation efforts. Key questions for mitigation are the viability of solutions such as alternative fuel cars, the roles of government and private sector [28] [29], and how early the switch to these technologies would have to be in order to maintain the lifestyle of a country or even prevent changes to the Earth's carrying capacity.

Alternative sources for oil

Alternatives are energy sources other than conventional oil and natural gas which can be used instead in one or more applications, such as:

  • a prime energy source to generate electricity
  • a transportation fuel
  • for space heating
  • for water heating
  • an ingredient in plastics, pesticides, pharmaceuticals, semiconductors, and fertilizers
  • a lubricant in industrial machinery and manufacturing.

Popular alternatives include

One near-term alternative source of liquid fuel is the Athabasca Tar Sands in Alberta, Canada. Production from this source is around 1 million bbl/day as of 2006, and is expected to build up to 3.2 million bbl/day by 2015. Higher oil prices have overcome the high costs of extracting heavy oil from this source. The current extraction process, however, requires large inputs of scarce natural gas and fresh water. The figure for recoverable reserves from this source is currently (mid 2006) around 180 billion barrels (cf. the Saudi Arabian reserve of about 260 billion barrels of conventional oil). A similar field, the Orinoco tar sands in Venezuela, is also being exploited. These two are the largest known fields of tar (i.e., bitumen) sands.

Synthetic fuel, created via coal liquefaction, requires no engine modifications for use in standard automobiles. As a byproduct of oil embargos during Apartheid in South Africa, Sasol, using the Fischer-Tropsch process, developed relatively low-cost coal-based fuel. Currently, over 50% of fuel (mostly diesel) used by automobiles in South Africa is produced from coal. With crude-oil prices currently around $75 per barrel, this process is now cost-effective; however the process emits large amounts of carbon dioxide, thus contributing substantially to global warming.

Depending on when global oil production peaks, these alternatives may not yet be commercially available or scalable to replace conventional oil. Promoting conservation and improved efficiency are seen as the easiest and least expensive courses of action to deal with rising prices of scarce oil and natural gas. Modern diesel and hybrid vehicles use off-the-shelf technology and achieve superior fuel efficiency over traditional models.

Energy return on energy investment

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).

Since, for economic reasons, the cheapest and easiest to extract sources of energy are used first, the EROEI decreases over time. Currently, between one and five barrels of oil are recovered for each barrel-equivalent of energy used in the recovery process. While any source of energy with an EROEI near or below 1.0 would seem futile to exploit, there are special situations when this is not the case. Availability of cheap, but hard to transport, natural gas in some oil fields has led to using natural gas to fuel steam injection into oil fields. 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.

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.

Implications of a world peak

Gas coupon printed but not used in 1979's oil crisis
Gas coupon printed but not used in 1979's oil crisis
Oil depletion scenarios
Oil depletion scenarios

According to the Hirsch report prepared for the U.S. Dept. of Energy, a global decline in oil production will have serious social and economic implications without due preparation. Peak Oil theorists argue that global economic growth relies on cheap energy[30], and oil contributes significantly to the worldwide energy pool, particularly for transportation. A decline in energy supply might slow or even reverse growth; however, it must be noted that the world economy has continued to grow despite multi-year drops in total energy consumption. For example, from 1979 through 1983, total world energy consumption dropped by 3%, including a 14.8% drop in oil consumption[31], yet world GDP growth for that 5-year period was still about 2.5% per year[32].

Initially a peak in oil production would manifest itself as rapidly escalating prices and a worldwide oil shortage. This shortage would differ from shortages of the past because the fundamental cause would be geological, not political. While past shortages stemmed from a temporary insufficiency of supply, crossing Hubbert's Peak means that the production of oil continues to decline, so demand must be reduced to meet supply. The effects of such a shortage depend on the rate of decline and the development and adoption of alternatives. If alternatives are not forthcoming, then the many products and services produced with oil become scarcer, leading to lower living standards in all countries. Scenarios range from doomsday scenarios to no noticeable problems thanks to new technologies. In order to deal with potential problems from peak oil, Colin Campbell has proposed the Rimini protocol.

It is unlikely that the actual peak in global oil production will be a direct catalyst of global economic decline. Instead, economic turbulence could be precipitated by the realization of the financial and investment world that "peak oil" (and natural gas) is either imminent or has already occurred. Significant indications of economic volatility have manifested themselves in the largest increase in inflation rates in 15 years (Sept. 2005), due mostly to higher energy costs. Since natural gas is the single largest feedstock used to produce fertilizers, an increase in natural gas prices could provide upward pressure on food costs, in addition to the increase in the transportation component of food prices.

These possible impacts of peaking oil, exacerbated by global competition over scarce remaining oil supplies, have led some analysts to predict dire consequences for conventional oil-dependent economies. According to oil industry analyst Jan Lundberg, "Based on today's intensifying trends, warning signs and an understanding of history, one must be ready to see the fossil-fueled phase come to an end most abruptly. When common practices cannot be maintained and too many people suddenly begin hoarding scant supplies, the desired resource dries up. This causes ramifications that quickly compound whatever triggered the crisis." This scenario is referred to by Lundberg as Petrocollapse. Contrasting views note that most uses of oil, from plastics to transportation fuels, have substitutes, blunting the impact of declining petroleum supplies.

Current events pertaining to oil production

In late 2005 as oil prices rose, greater attention was focused on Hubbert's theory and its potential implications. While Hubbert himself is still not widely known, debates and discussions about rising fuel prices have become commonplace in the media and elsewhere almost everywhere in the world. However, oil and gas prices are notoriously volatile and price increases have been caused by numerous other factors, though there is a general agreement that increased demand has been the major factor, with such increased demand bringing the Hubbert peak closer than would have been predicted otherwise. In June 2005, OPEC admitted that they would 'struggle' to pump enough oil to meet pricing pressures for the fourth quarter of that year. The summer and winter of 2005 brought oil prices to a new high (not adjusted for inflation). This may be a sign of increasing demand having started to outstrip supply or it may just be that the various geopolitical forces in the regions where oil is produced are limiting the available supply. One other explanation for the rising oil prices is that it has been a sign of too much paper money and not too little oil. In this view, dramatically higher prices of all commodities and real estate indicates rising inflation.

The Burgan Field, Kuwait's largest oil field, peaked in November 2005 [33]. In March 2006, Fernado Canales, the Energy Secretary of Mexico, announced that Mexico's giant Cantarell Field peaked in 2005 [34]. Burgan and Cantarell are among the largest fields in the world. Only Saudi Arabia's Ghawar is larger and it may have entered depletion in 2006 [35].

As awareness of Peak Oil increases, there are also a number of events being organized to allow for further education and discussion. For example, the Third U.S. Conference on Peak Oil and Community Solution [36] was announced for September 2006 in Yellow Springs, Ohio.


Economist Michael Lynch[37] argues that the theory behind the Hubbert curve is overly simplistic, and that available evidence contradicts some of the more specific predictions.[38]

Critics such as Leonardo Maugeri, vice president for the Italian energy company ENI, point out that Hubbert peak supporters such as Campbell previously predicted a peak in global oil production in both 1989 and 1995[39], based on oil production data available at that time. Maugeri claims that nearly all of the estimates do not take into account non-conventional oil even though the availability of these resources is (supposedly) huge and the costs of extraction and processing, while still very high, are falling due to improved technology. Furthermore, he notes that the recovery rate from existing world oil fields has increased from about 22% in 1980 to 35% today due to new technology and predicts this trend will continue. The ratio between proven oil reserves and current production has constantly improved, passing from 20 years in 1948 to 35 years in 1972 and reaching about 40 years in 2003. These improvements occurred even with low investment in new exploration and upgrading technology due to the low oil prices during the last 20 years.

More generally, the supply of oil may be somewhat elastic in both the short term and the long term. Higher prices may encourage greater production and the use of more expensive extraction approaches. Over time, the current higher oil prices may well cause increased investment. However, absent added reserves or alternative sources, this may only delay the peak, rather than eliminating the peak altogether, and accelerate the depletion of reserves.

Proponents of "abiotic oil", often referred to or dismissed as a "fringe theory" believed by virtually no notable U.S. geologists, are skeptical of any statistical analyses containing as a given the nonrenewable "fossil" origin theories of petroleum. This Abiogenic Theory, also called the Abiotic Theory, or the Russian-Ukrainian Theory--that not all oil is fossilized bio matter, but occurs through other geologic processes, and thus is not so severely limited in supply--is believed to be true by many geologists in Russia and the Ukraine.

Part of the current debate revolves around energy policy, and whether to shift funding to increasing energy conservation, fuel efficiency, and alternative energy sources like solar or nuclear power. Campbell's critics, such as Michael Lynch and Freddy Hutter, claim that his research data is sloppy. They point to the date of the coming peak, which was initially projected to occur by 2000, but has now been pushed back to 2010, and note that Campbell's predictions for world oil production are strongly biased towards underestimates[40]. However, Campbell and his supporters insist that when the peak occurs is not as important as the realization that the peak is coming. Throughout 2001-2003, in his monthly newsletters, Campbell maintained that his 1996 prediction of a peak in 2000 was unchallenged, despite Hutter's alerts of increasing production levels. Finally in his April 2004 Newsletter, Campbell relented and shifted the peak to 2010. Later this was brought forward to 2007 but in October 2005, was shifted back to 2010. These shifts between predicted dates occur because of the systemic lack of accurate oil reserve data--with no truly accurate data we will not know when the peak occurs.

Another controversy was the status of the Hubbert Peak of conventional oil. Hutter claimed throughout 2004 that Campbell's own data illustrated that the Peak had passed unceremoniously in the Spring of 2004. The ASPO Newsletter continued to show the extraction peak in 2005 and/or 2006. Finally in August of 2005, Campbell again relented and began publishing that indeed the Peak had passed in 2004.

Further, the scenarios constructed by peak oil proponents are said to fail to consider the potential of backstop technologies such as ethanol-based fuels, coal liquefaction, gas-to-liquids (GTL) and other substitutes for crude oil. Coal liquefaction in particular becomes economically feasible, according to some estimates, at a sustained oil price of $32/barrel[41]—a price less than half the market price as of March 2006. Peak oil proponents argue that such technologies are much more costly and polluting than conventional oil and that they cannot be produced in sufficient quantity to replace rapidly declining post-peak supplies of conventional oil.

Hubbert peak for Gas

Because gas transport is a complicated operation,the global peak of gas is less important than the peak per continent.The North American peak happened in 2001, according to Western Gas Resources Inc; according to Doug Reynolds, the peak will occur in 2007 [42]; according to Bently, production will peak anywhere from 2010 to 2020 (Bentley, 2002).

Longterm Hubbert peaks


Peak is still very far,but we can observe the example of anthracite in the USA, a hie grade coal, that has peaked in the 1920's.


    1. ^ The Shape of World Oil Peaking: Learning From Experience by Robert L. Hirsch [1]
  • "Feature on United States oil production." (November, 2002) ASPO Newsletter #23.
  • Hubbert, M.K. (1982). Techniques of Prediction as Applied to Production of Oil and Gas, US Department of Commerce, NBS Special Publication 631, May 1982

See also

Global fossil carbon emissions, an indicator of consumption, for 1800-2000.  Total is black.  Oil is in blue.
Global fossil carbon emissions, an indicator of consumption, for 1800-2000. Total is black. Oil is in blue.





Michael C. Ruppert, Crossing the Rubicon: The Decline of the American Empire at the End of the Age of Oil


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