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== '''[[Global warming]]''' ==
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''by [[User:Gareth Leng|Gareth Leng]], [[User:Raymond Arritt|Raymond Arritt]], [[User:Robert Badgett|Robert Badgett]], [[User:Nereo Preto|Nereo Preto]], [[User:Anthony Sebastian|Anthony Sebastian]], and [[User:Benjamin Seghers|Benjamin Seghers]] <small>(and [[User:Milton Beychok|Milton Beychok]], [[User:David Finn|David Finn]], [[User:Greg Harris|Greg Harris]], [[User:Ed Poor|Ed Poor]], [[User:Larry Sanger|Larry Sanger]], [[User:John Stephenson|John Stephenson]] and [[User:Paul Wormer|Paul Wormer]])</small>''
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==Footnotes==
[[Image:105582main GlobalWarming 2060 lg.jpg|right|thumb|Annual average global warming by the year 2060 simulated and plotted as color differences using EdGCM|250px]] 
 
'''[[Global warming]]''' is the increase in the average temperature of the Earth's near-surface air and oceans in recent decades and its projected continuation.  There is strong evidence that significant global warming is occurring; this evidence comes from direct measurements of rising surface air temperatures and subsurface ocean temperatures and from phenomena such as increases in average global sea levels, retreating glaciers, and changes to many physical and biological systems. It is likely that most of the warming in recent decades is attributable to human activity, particularly the burning of fossil fuels and deforestation.
 
Global average air temperature near the Earth's surface rose by 0.74 ± 0.18&nbsp;°[[Celsius|C]] (1.33 ± 0.32&nbsp;°F) from 1906 to 2005. The prevailing scientific view,
 
<ref name = Doran>See [http://tigger.uic.edu/~pdoran/012009_Doran_final.pdf Doran (2009)] 'Examining the Scientific Consensus
on Climate Change' for information on a poll of research-active climate scientists, other researchers and the public regarding the scientific consensus on global warming ''Eos'' 90: 21-2</ref> as represented by the science academies of the major industrialized nations<ref name = "academies">[http://nationalacademies.org/onpi/06072005.pdf Joint science academies’ statement: Global response to climate change]
*"There will always be uncertainty in understanding a system as complex as the world’s climate. However there is now strong evidence that significant global warming is occurring. The evidence comes from direct measurements of rising surface air temperatures and subsurface ocean temperatures and from phenomena such as increases in average global sea levels, retreating glaciers, and changes to many physical and biological systems. It is likely that most of the warming in recent decades can be attributed to human activities (IPCC 2001). This warming has already led to changes in the Earth's climate."</ref>
and the ''[http://www.ipcc.ch/ Intergovernmental Panel on Climate Change]'',<ref name=grida7>{{cite web | url=http://www.ipcc.ch/publications_and_data/ar4/wg1/en/spm.html|title=Summary for Policymakers|work=Climate Change 2007: The Physical Science Basis. Contribution of Working Group I to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change|date=2007}}
*"Most of the observed increase in global average temperatures since the mid-20th century is very likely due to the observed increase in anthropogenic greenhouse gas concentrations...Discernible human influences now extend to other aspects of climate, including ocean warming, continental-average temperatures, temperature extremes and wind patterns" </ref> it is very likely that most of the temperature increase since the mid-20th century has been caused by increases in atmospheric greenhouse gas concentrations produced by human activity. Climate models predict that average global surface temperatures will increase by a further 1.1 to 6.4 °C (2.0 to 11.5 °F) by the end of the century, relative to 1980–1999.<ref name=grida7/> The range of values reflects differing assumptions of future greenhouse gas emissions and results of models that differ in their sensitivity to increases in greenhouse gases.<ref name=grida7/>  
 
Scientists have not yet quantitatively assessed the potential self-accelerating effects of global-warming itself, either on threshold or rate.  Melting of permafrost, for example, causes increased production and atmospheric release of such newly produced as well as anciently stored methane gas, which  “….packs a far greater warming punch than [carbon dioxide] (CO<sub>2</sub>),”<ref name=walker2007>Walker G (2007) [http://dx.doi.org/10.1038/446718a Climate Change 2007: A world melting from the top down] ''Nature'' 446:718-21</ref> possibly as much as 25 times that of CO<sub>2</sub> per unit mass.<ref name=simpson2009>Simpson (2009) [http://www.ScientificAmerican.com/Earth3 "The Peril Below the Ice"] ''Scientific American Earth 3.0'' pp 30-7</ref>
 
An increase in global temperatures will cause the sea level to rise, glaciers to retreat, sea ice to melt, and changes in the amount, geographical distribution and seasonal pattern of precipitation. There may also be changes in the frequency and intensity of extreme weather events. These  will have many practical consequences, including changes in agricultural yields and impacts on human health.<ref>[http://www.ipcc.ch/publications_and_data/ar4/wg2/en/ch19s19-3-6.html Schneider ''et al.'' (2007)]. [http://www.ipcc.ch/publications_and_data/ar4/wg2/en/ch19.html Assessing key vulnerabilities and the risk from climate change]. In Parry ML ''et al.'' (eds) ''[http://www.ipcc.ch/publications_and_data/ar4/wg2/en/contents.html Climate Change 2007: Impacts, Adaptation and Vulnerability. Contribution of Working Group II to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change]'' Cambridge University Press pp 779-810
*"There is new and stronger evidence of observed impacts of climate change on unique and vulnerable systems (such as polar and high-mountain communities and ecosystems), with increasing levels of adverse impacts as temperatures increase (very high confidence).
*There is new evidence that observed climate change is likely to have already increased the risk of certain extreme events such as heatwaves, and it is more likely than not that warming has contributed to the intensification of some tropical cyclones, with increasing levels of adverse impacts as temperatures increase (very high confidence).
*The distribution of impacts and vulnerabilities is still considered to be uneven, and low-latitude, less-developed areas are generally at greatest risk due to both higher sensitivity and lower adaptive capacity; but there is new evidence that vulnerability to climate change is also highly variable within countries, including developed countries." </ref> Scientific uncertainties include the extent of climate change expected in the future, and how changes will vary around the globe. There is political and public debate about what action should be taken to reduce future warming or to adapt to its consequences. The Kyoto Protocol, an international agreement aimed at reducing greenhouse gas emissions, was adopted by 169 nations.
''[[Global warming|.... (read more)]]''
 
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Latest revision as of 09:19, 11 September 2020

The Mathare Valley slum near Nairobi, Kenya, in 2009.

Poverty is deprivation based on lack of material resources. The concept is value-based and political. Hence its definition, causes and remedies (and the possibility of remedies) are highly contentious.[1] The word poverty may also be used figuratively to indicate a lack, instead of material goods or money, of any kind of quality, as in a poverty of imagination.

Definitions

Primary and secondary poverty

The use of the terms primary and secondary poverty dates back to Seebohm Rowntree, who conducted the second British survey to calculate the extent of poverty. This was carried out in York and was published in 1899. He defined primary poverty as having insufficient income to “obtain the minimum necessaries for the maintenance of merely physical efficiency”. In secondary poverty, the income “would be sufficient for the maintenance of merely physical efficiency were it not that some portion of it is absorbed by some other expenditure.” Even with these rigorous criteria he found that 9.9% of the population was in primary poverty and a further 17.9% in secondary.[2]

Absolute and comparative poverty

More recent definitions tend to use the terms absolute and comparative poverty. Absolute is in line with Rowntree's primary poverty, but comparative poverty is usually expressed in terms of ability to play a part in the society in which a person lives. Comparative poverty will thus vary from one country to another.[3] The difficulty of definition is illustrated by the fact that a recession can actually reduce "poverty".

Causes of poverty

The causes of poverty most often considered are:

  • Character defects
  • An established “culture of poverty”, with low expectations handed down from one generation to another
  • Unemployment
  • Irregular employment, and/or low pay
  • Position in the life cycle (see below) and household size
  • Disability
  • Structural inequality, both within countries and between countries. (R H Tawney: “What thoughtful rich people call the problem of poverty, thoughtful poor people call with equal justice a problem of riches”)[4]

As noted above, most of these, or the extent to which they can be, or should be changed, are matters of heated controversy.

Footnotes

  1. Alcock, P. Understanding poverty. Macmillan. 1997. ch 1.
  2. Harris, B. The origins of the British welfare state. Palgrave Macmillan. 2004. Also, Oxford Dictionary of National Biography.
  3. Alcock, Pt II
  4. Alcock, Preface to 1st edition and pt III.