Changes

==Natural variability of the climate system==

==Natural variability of the climate system==

Secular scientists think that the Earth has experienced numerous [[Ice Age|ice age]]s over two million years, during which global temperatures dropped approximately 6 degrees Celsius and then returned to normal. The frigid temperatures allowed ice sheets to expand southward, covering much of [[Asia]], [[Europe]], and [[North America]]. The cooling associated with ice ages is gradual, while the terminations are relatively rapid. However, even the rapid terminations of ice ages take centuries to millennia.

Secular scientists think that the Earth has experienced numerous [[Ice Age|ice age]]s over two million years, during which global temperatures dropped approximately 6 degrees Celsius and then returned to normal. The frigid temperatures allowed ice sheets to expand southward, covering much of [[Asia]], [[Europe]], and [[North America]]. The cooling associated with ice ages is gradual, while the terminations are relatively rapid. However, even the rapid terminations of ice ages take centuries to millennia.

==Global Warming on other Planets==

==Global Warming on other Planets==

And it's not just the earth that has variations.  Since the Viking spacecraft reached Mars in the 1970's until recent readings were taken, the average temperature on Mars has risen 1.1 degrees Fahrenheit just as the average temperature on the earth has risen.  Since human industrialization is probably not to blame for the change on Mars, other causes are being considered.  One possibility is that dust storms are changing the albedo of the planet, allowing it to warm, while another possibility is that solar variations from the sun are causing the warming.<ref>http://www.space.com/scienceastronomy/070404_gw_mars.html</ref><ref>http://www.heartland.org/Article.cfm?artId=17977</ref>

And it's not just the earth that has variations.  Since the Viking spacecraft reached Mars in the 1970's until recent readings were taken, the average temperature on Mars has risen 1.1 degrees Fahrenheit just as the average temperature on the earth has risen.  Since human industrialization is probably not to blame for the change on Mars, other causes are being considered.  One possibility is that dust storms are changing the albedo of the planet, allowing it to warm, while another possibility is that solar variations from the sun are causing the warming.<ref>http://www.space.com/scienceastronomy/070404_gw_mars.html</ref><ref>http://www.heartland.org/Article.cfm?artId=17977</ref>

==Politics of global warming==

==Politics of global warming==

The global average surface temperature warmed about 0.5&nbsp;°C (0.9&nbsp;°F) over the second half of the 20th Century,{{Fact-science}} and to some the warming appears to be related to increases in carbon dioxide and other greenhouse gases. The possibility of adverse consequences has become a major concern for environmentalists.

The global average surface temperature warmed about 0.5&nbsp;°C (0.9&nbsp;°F) over the second half of the 20th Century,{{Fact-science}} and to some the warming appears to be related to increases in carbon dioxide and other greenhouse gases. The possibility of adverse consequences has become a major concern for environmentalists.

have claimed that scientists are 90% sure that over 50% of the observed global warming in recent decades is human-caused, and that continued global warming should be expected over at lease the next century. Science published a literature search by Naomi Oreskes concluding that "scientific consensus" overwhelmingly supports the IPCC reports. <ref>http://www.sciencemag.org/cgi/content/full/306/5702/1686]</ref>

have claimed that scientists are 90% sure that over 50% of the observed global warming in recent decades is human-caused, and that continued global warming should be expected over at lease the next century. Science published a literature search by Naomi Oreskes concluding that "scientific consensus" overwhelmingly supports the IPCC reports. <ref>http://www.sciencemag.org/cgi/content/full/306/5702/1686]</ref>

Several prominent scientists have pointed out the [[politicized science]] of the UN's assessment methods. The scientific reports are submitted to a panel of representatives appointed by each country in the IPCC. Several scientists have complained about their work being misrepresented by the U.N.{{Fact}}

Several prominent scientists have pointed out the [[politicized science]] of the UN's assessment methods. The scientific reports are submitted to a panel of representatives appointed by each country in the IPCC. Several scientists have complained about their work being misrepresented by the U.N.

There is wide agreement among the American public that Global Warming is a reality. A poll conducted March 11-14 of 2007 found that the majority of the American public (59%) believes we are already seeing the effects of Global Warming, an additional 3% and 8% respectively believe they will see the effects with in a few years or within their lifetime, and 19% believe that Global Warming will be seen, not in their lifetime, but in future generations—only a small minority 8% believe that Global Warming will never happen. <ref>Poling report on Gallup poll for March 11-14, 2007[http://www.pollingreport.com/enviro.htm]</ref>.

There is wide agreement among the American public that Global Warming is a reality. A poll conducted March 11-14 of 2007 found that the majority of the American public (59%) believes we are already seeing the effects of Global Warming, an additional 3% and 8% respectively believe they will see the effects with in a few years or within their lifetime, and 19% believe that Global Warming will be seen, not in their lifetime, but in future generations—only a small minority 8% believe that Global Warming will never happen. <ref>Poling report on Gallup poll for March 11-14, 2007[http://www.pollingreport.com/enviro.htm]</ref>.

== Scientists ==

== Scientists ==

[[Image:Rogerrevelle.jpg|thumb|right|100px|Roger Revelle, Al Gore's mentor.]]

[[Image:Rogerrevelle.jpg|thumb|right|100px|Roger Revelle, Al Gore's mentor.]]

==External links==

==External links==

*[http://schwinger.harvard.edu/~motl/global-temperature-not-exist.pdf Does a global temperature exist?], ''Journal of Non-Equilibrium Thermodynamics'', June 2007.

*[http://schwinger.harvard.edu/~motl/global-temperature-not-exist.pdf Does a global temperature exist?], ''Journal of Non-Equilibrium Thermodynamics'', June 2007.

*[http://www.magma.ca/~hurleyp/FightingTheHoax.htm Fighting the Hoax]

*[http://www.magma.ca/~hurleyp/FightingTheHoax.htm Fighting the Hoax]

==References==

==References==

<references/>

<references/>

[[category:earth science]]

[[category:earth science]]

[[category:Liberal Falsehoods]]

[[category:Liberal Falsehoods]]