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Global warming alarmists, such as Al Gore and Mitt Romney, who advocate for more government spending, regulations and taxes to make a gallon of gas even more expensive, claim that current global temperatures are "unprecedented." Nothing could be more scientific-nonsense when, clearly, peer-reviewed study after study shows that current modern warming is lukewarm versus previous periods.
The Gore-Romney-Obama nonsense about "unprecedented" warming can't even hold its own during the 20th century, as a new study by Yi et al. establishes without a reasonable doubt. Early 20th century temperatures prior to large human CO2 emissions were hotter than temperatures in the 1990s and early 21st century.
And to emphasize the anti-science hysteria from Democrat/Republican big government liberals/leftists/progressives, this study shows how absurd their claim is that climate change is only due to recent human CO2 emissions.
"In the ongoing global warming debate there is often a significant difference between the perception of what is going on with the Earth’s climate when compared to what is actually going on. There is no greater example of this than the summer temperatures in the Northern Hemisphere...A recent study is probably the highest resolution reconstruction using temperature and precipitation records from the region and then correlating to tree-ring data to create a high resolution reconstruction of the summer temperatures for North-Central China...it is clear that the peak of the modern warming cycle for the summer months took place 70-80 years ago. It should be noted that the United States set the all time temperature record for 50% of the states back in the 1930′s."
"We concluded that (1) the droughts, occurred during the years of 1484 AD, 1585–1587 AD, 1689–1691 AD, 1784–1786 AD and 1876–1878 AD, were the results of rainless and torrid combination; (2) the droughts, occurred during the years of 1560–1561 AD, 1599–1601 AD, 1609 AD, 1615–1617 AD, 1638–1641 AD and 1899–1901 AD, were first caused by rainless summer, and then controlled by low precipitation and/or high temperature; (3) the droughts, occurred during the years of 1527–1529 AD, 1720–1722 AD, 1813–1814 AD, 1856–1857 AD and 1926–1930 AD, were first caused by torrid summer, and then controlled by both low precipitation and high temperature; (4) the dominant climate pattern within the study area consisted of warm–dry and cold–wet alternations, and the recessive pattern consisted of cold–dry and warm–wet alternations. We also showed that the drought/flood index is a valuable climate proxy in quantitative reconstructions, especially in places where tree-ring data is not available." [Liang Yi, Hongjun Yu, Junyi Ge, Zhongping Lai, Xingyong Xu, Li Qin and Shuzhen Peng 2011: Climatic Change]
Additional "unprecedented"-warming and peer-reviewed postings. Modern temperature charts.