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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 10:19, 11 September 2020

1901 photograph of a stentor (announcer) at the Budapest Telefon Hirmondó.

Telephone newspaper is a general term for the telephone-based news and entertainment services which were introduced beginning in the 1890s, and primarily located in large European cities. These systems were the first example of electronic broadcasting, and offered a wide variety of programming, however, only a relative few were ever established. Although these systems predated the invention of radio, they were supplanted by radio broadcasting stations beginning in the 1920s, primarily because radio signals were able to cover much wider areas with higher quality audio.

History

After the electric telephone was introduced in the mid-1870s, it was mainly used for personal communication. But the idea of distributing entertainment and news appeared soon thereafter, and many early demonstrations included the transmission of musical concerts. In one particularly advanced example, Clément Ader, at the 1881 Paris Electrical Exhibition, prepared a listening room where participants could hear, in stereo, performances from the Paris Grand Opera. Also, in 1888, Edward Bellamy's influential novel Looking Backward: 2000-1887 foresaw the establishment of entertainment transmitted by telephone lines to individual homes.

The scattered demonstrations were eventually followed by the establishment of more organized services, which were generally called Telephone Newspapers, although all of these systems also included entertainment programming. However, the technical capabilities of the time meant that there were limited means for amplifying and transmitting telephone signals over long distances, so listeners had to wear headphones to receive the programs, and service areas were generally limited to a single city. While some of the systems, including the Telefon Hirmondó, built their own one-way transmission lines, others, including the Electrophone, used standard commercial telephone lines, which allowed subscribers to talk to operators in order to select programming. The Telephone Newspapers drew upon a mixture of outside sources for their programs, including local live theaters and church services, whose programs were picked up by special telephone lines, and then retransmitted to the subscribers. Other programs were transmitted directly from the system's own studios. In later years, retransmitted radio programs were added.

During this era telephones were expensive luxury items, so the subscribers tended to be the wealthy elite of society. Financing was normally done by charging fees, including monthly subscriptions for home users, and, in locations such as hotel lobbies, through the use of coin-operated receivers, which provided short periods of listening for a set payment. Some systems also accepted paid advertising.

Footnotes