Changes

[[File:Global temp chart.jpg|thumb|right|Graph showing temperature connections between solar activity and volcanic eruptions, against a backdrop of historical events.]]

[[File:Global temp chart.jpg|thumb|right|Graph showing temperature connections between solar activity and volcanic eruptions, against a backdrop of historical events.]]

'''Anthropogenic global warming''' (AGW) is a theory that suggests that human activity is causing the [[Earth]] to warm. The theory posits that greenhouse gases, including carbon dioxide, methane, nitrous oxide, and water vapor, trap solar warmth on the planet. Computer models suggest that industrial and vehicular emissions could lead to catastrophic warming. Some [[Leftist]]s use this theory as a basis to propose cuts in energy production and consumption and promote de-industrialization.

'''Anthropogenic global warming''' (AGW) is a theory that suggests that human activity is causing the [[Earth]] to warm. The theory posits that greenhouse gases, including carbon dioxide, methane, nitrous oxide, and water vapor, trap solar warmth on the planet. Computer models suggest that industrial and vehicular emissions could lead to catastrophic warming. [[Leftist]]s use this theory as a basis to propose cuts in energy production and consumption and promote de-industrialization.

An average of the various radiosonde (weather balloon) and satellite temperature records shows a warming trend of less that one half a degree Celsius in the lower troposphere between 1979 and 2014. This corresponds to a rate of 1.8 degrees per century. If the AGW theory was correct, the Earth would be warming at twice this rate, according to an average of 102 climate models. The various doomday forecasts prevalent in the media are based on these models, which have already proven to be inaccurate.<ref>"[https://www.newcriterion.com//cm/images/THE%20CLIMATE%20SURPRISE%20PAMPHLET.pdf The Climate Surprise Pamphet]", ''The New Criterion'', 2016. Taken from chart "All 3 Global Temperature Dataset Types Disagree with the Climate Model During the Period of Greatest Greenhouse Concentration."</ref>

An average of the various radiosonde (weather balloon) and satellite temperature records shows a warming trend of less that one half a degree Celsius in the lower troposphere between 1979 and 2014. This corresponds to a rate of 1.8 degrees per century. If the AGW theory was correct, the Earth would be warming at at of 3.1 degrees per century, according to an average of 102 climate models used by the Intergovernmental Panel on Climate Change (IPCC). The various doomday forecasts prevalent in the media are based on these models, which have already proven to be inaccurate.<ref>"[https://www.newcriterion.com//cm/images/THE%20CLIMATE%20SURPRISE%20PAMPHLET.pdf The Climate Surprise Pamphet]", ''The New Criterion'', 2016. Taken from chart "All 3 Global Temperature Dataset Types Disagree with the Climate Model During the Period of Greatest Greenhouse Concentration."</ref>

Radiosonde and satellite data are the most accurate sources for global temperature, but they do not go back far enough to establish a relevant trend. A reanalysis of weather station data for 1943 to 2012 by U.S. climate researcher Roy Spencer shows that after a cooler period in the 1960s and 1970s, U.S. temperatures returned to their earlier level. Unlike official temperature records, Spencer's data includes only those stations that record at a consistent time of day.<ref name="Spencer" />  

Radiosonde and satellite data are the most accurate sources for global temperature, but they do not go back far enough to establish a relevant trend. A reanalysis of weather station data for 1943 to 2012 by U.S. climate researcher Roy Spencer shows that after a cooler period in the 1960s and 1970s, U.S. temperatures returned to their earlier level. Unlike official temperature records, Spencer's data includes only those stations that record at a consistent time of day.<ref name="Spencer" />  

Difficulties with the theory:

Difficulties with the theory:

*'''Carbon dioxide is insignificant as a greenhouse gas.''' The level of CO₂ in the Earth's atmosphere is only 400 parts per million. Ninety to 95 percent of the greenhouse effect is due to water vapor.<ref>Friedenreich and Ramaswamy, "Solar Radiation Absorption by Carbon Dioxide, Overlap with Water, and a Parameterization for General Circulation Models," Journal of Geophysical Research 98 (1993):7255-7264)</ref> The Intergovernmental Panel on Climate Change (IPCC) claims that water vapor acts as a "positive feedback," i.e. warming creates more humidity, which leads to additional warming. There are humidity measurements going back to 1948, and they show no upward trend.<ref>"[https://wattsupwiththat.com/global-climate/ global climate]," ''Watt's Up with That''</ref> More humidity could lead to more clouds and therefore to cooling and to negative feedback. So why assume positive feedback? AGW works only if water vapor is a positive feedback, so that is what the IPCC must claim.<br/>Although Obama has denounced elevated carbon dioxide levels as "carbon pollution," greenhouse operators commonly increase the level of CO₂ to 1,000 ppm or more to enhance plant growth.<ref>"[https://www.sciencedaily.com/releases/2015/12/151210101819.htm Plant growth enhanced by increased carbon dioxide, but food webs give rise to significant variations]", ''Science News'', December 10, 2015.<br/>Harrison H. Schmitt and William Happer, "[http://arizonaskywatch.com/article/articles/In%20defense%20of%20carbon%20dioxide.pdf In Defense of Carbon Dioxide]," ''Wall Street Journal'', May 8, 2013.</ref>

*'''Carbon dioxide is insignificant as a greenhouse gas.''' The level of CO₂ in the Earth's atmosphere is only 400 parts per million. Ninety to 95 percent of the greenhouse effect is due to water vapor.<ref>Friedenreich and Ramaswamy, "Solar Radiation Absorption by Carbon Dioxide, Overlap with Water, and a Parameterization for General Circulation Models," Journal of Geophysical Research 98 (1993):7255-7264)</ref> The IPCC claims that water vapor acts as a "positive feedback," i.e. warming creates more humidity, which leads to additional warming. There are humidity measurements going back to 1948, and they show no upward trend.<ref>"[https://wattsupwiththat.com/global-climate/ global climate]," ''Watt's Up with That''</ref> More humidity could lead to more clouds and therefore to cooling and to negative feedback. So why assume positive feedback? AGW works only if water vapor is a positive feedback, so that is what the IPCC must claim.<br/>Although Obama has denounced elevated carbon dioxide levels as "carbon pollution," greenhouse operators commonly increase the level of CO₂ to 1,000 ppm or more to enhance plant growth.<ref>"[https://www.sciencedaily.com/releases/2015/12/151210101819.htm Plant growth enhanced by increased carbon dioxide, but food webs give rise to significant variations]", ''Science News'', December 10, 2015.<br/>Harrison H. Schmitt and William Happer, "[http://arizonaskywatch.com/article/articles/In%20defense%20of%20carbon%20dioxide.pdf In Defense of Carbon Dioxide]," ''Wall Street Journal'', May 8, 2013.</ref>

[[Image:NASA-1024x933.jpg|thumb|right|A composite map of [[Antarctica]] showing areas of greatest warming in red. The Wilkins Ice Shelf lies off the peninsula in the top left corner, and shows extensive warming. Overall, Antarctica shows little warming, and many areas to the  East (right) are almost cooling.<ref>Roberts, Greg (April 18, 2009). [http://www.news.com.au/antarctic-ice-is-growing-not-melting-away/story-0-1225700043191 "Antarctic ice is growing, not melting away."] News.com.au.  Retrieved on September 25, 2014.</ref>]]

[[Image:NASA-1024x933.jpg|thumb|right|A composite map of [[Antarctica]] showing areas of greatest warming in red. The Wilkins Ice Shelf lies off the peninsula in the top left corner, and shows extensive warming. Overall, Antarctica shows little warming, and many areas to the  East (right) are almost cooling.<ref>Roberts, Greg (April 18, 2009). [http://www.news.com.au/antarctic-ice-is-growing-not-melting-away/story-0-1225700043191 "Antarctic ice is growing, not melting away."] News.com.au.  Retrieved on September 25, 2014.</ref>]]

*'''The Earth has warmed or cooled many times. Historically, warm periods are associated with favorable climate.''' The [[Roman Warm Period]] (250 BC to 400 AD) was followed by the Dark Ages Cold Period (450-950 AD).<ref>"[http://www.co2science.org/subject/d/summaries/dacpeurope.php Dark Ages Cold Period (Europe) - Summary]", ''CO₂ Science'', 1 June 2005.</ref> The Medieval Warm Period lasted from 900 to 1300. From the 14th century to the early 19th century, there was a Little Ice Age.<ref>Bastasch, Michael, "[http://dailycaller.com/2013/12/13/study-earth-was-warmer-in-roman-medieval-times/ Study: Earth was warmer in Roman, Medieval times]", ''The Daily Caller''. For a peer-reviewed paper, see Moberg, A., et al. 2005 "[ftp://ftp.ncdc.noaa.gov/pub/data/paleo/contributions_by_author/moberg2005/nhtemp-moberg2005.txt 2,000-Year Northern Hemisphere Temperature Reconstruction]", ''World Data Center for Paleoclimatology''. The Moberg data set is charted [https://i0.wp.com/i90.photobucket.com/albums/k247/dhm1353/Moberg-1.png here].</ref>

*'''The Earth has warmed or cooled many times. Historically, warm periods are associated with favorable climate.''' The [[Roman Warm Period]] (250 BC to 400 AD) was followed by the Dark Ages Cold Period (450-950 AD).<ref>"[http://www.co2science.org/subject/d/summaries/dacpeurope.php Dark Ages Cold Period (Europe) - Summary]", ''CO₂ Science'', 1 June 2005.</ref> The Medieval Warm Period lasted from 900 to 1300. From the 14th century to the early 19th century, there was a Little Ice Age.<ref>Bastasch, Michael, "[http://dailycaller.com/2013/12/13/study-earth-was-warmer-in-roman-medieval-times/ Study: Earth was warmer in Roman, Medieval times]", ''The Daily Caller''. For a peer-reviewed paper, see Moberg, A., et al. 2005 "[ftp://ftp.ncdc.noaa.gov/pub/data/paleo/contributions_by_author/moberg2005/nhtemp-moberg2005.txt 2,000-Year Northern Hemisphere Temperature Reconstruction]", ''World Data Center for Paleoclimatology''. The Moberg data set is charted [https://i0.wp.com/i90.photobucket.com/albums/k247/dhm1353/Moberg-1.png here].</ref>