* This graph is called the “hockey stick graph” because the curve looks like a hockey stick laid on its side (click on the footnote for a graphic illustration). The red part of the curve represents modern instrument-measured surface temperatures, the blue represents proxy data, the black line is a smoothed average of the proxy data, and the gray represents the margin of error with 95% confidence.  * This graph has been the subject of disputes in scientific journals,  congressional hearings,  and legal proceedings including a Freedom of Information Act lawsuit.  Just Facts presently does not have the resources to conclusively assess all the competing claims on this issue, but the facts we have verified are as follows: medieval warmth,” and shows the following graph of temperature changes for the Northern Hemisphere over the past 1,300 years.
This graph, which is called a “spaghetti graph,” is constructed with data from 12 proxy studies spliced with instrument-measured surface temperatures (the dark black line): * The fifth IPCC report (2013) states that challenges persist in reconstructing temperatures before the time of the instrumental record “due to limitations of spatial sampling, uncertainties in individual proxy records and challenges associated with the statistical methods used to calibrate and integrate multi-proxy information.” This report contains the following spaghetti graphs of proxy studies spliced with instrument-measured surface temperatures (the black lines): * In 2009, an unknown individual(s) released more than 1,000 emails (many dealing with proxy studies) from the University of East Anglia’s Climatic Research Unit (CRU).
He informed the * In 2013, “Forecast the Facts”—a “grassroots human rights organization dedicated to ensuring that Americans hear the truth about climate change”—published the following graphic purporting to show a recent photo of the North Pole: * After publishing an article documenting the facts above, Just Facts contacted Forecast the Facts to offer an opportunity to respond. As of January 2016, Forecast the Facts has not replied or issued a correction.  * The natural variability of Earth’s climate is such that a glacier formerly existed on Hawaii, and glaciers once covered almost all of Canada, New England, and the northern central United States: * In addition to carbon dioxide emissions from the use of fossil fuels, other factors that have been implicated by scientists as primary causes of modern climate change include but are not limited to: * A central debate among scientists about man-made greenhouse gases involves how much natural processes reduce or amplify the effects of these gases.
Positive feedbacks amplify the effects, and negative feedbacks diminish them. * The climate models included in the 2007 IPCC report are programmed with positive feedbacks for water vapor that more than double the warming effect of CO2. This is based upon the fact that warmer air evaporates more water, thus creating more water vapor, which is a greenhouse gas.  states that the feedbacks used in climate models are based upon “methods that …
Hopefully it will give some insight into the science and the people behind it.  Look at the instrumental record!
We hereby release a random selection of correspondence, code, and documents.
* The second IPCC report (1995) states that “data prior to 1400 are too sparse to allow the reliable estimation of global mean temperature” and shows a graph of proxy-derived temperatures for Earth’s Northern Hemisphere from 1400 onward with different details but a similar overall trend to the first report. * The third IPCC report (2001) states that the latest proxy studies indicate “the conventional terms of ‘Little Ice Age’ and ‘Medieval Warm Period’ appear to have limited utility in describing …
global mean temperature changes in past centuries.” The report contains the following graph of average temperature changes in Earth’s Northern Hemisphere, showing higher temperatures at present than at any time in the past 1,000 years.
do not allow any observational assessment” because many variables are involved, and “it is not possible …
to insure that only one variable is changing.” found that during 1973-2007, humidity increased in the lowest part of Earth’s atmosphere but decreased at higher altitudes, implying that the “long-term water vapor feedback is negative—that it would reduce rather than amplify” the warming effect of CO2.