Resolved: The Hockey Stick is likely correct

I'll accept that challenge and thank Con for the opportunity.THESIS: The Mean Surface Temperature of the Earth has risen by 0.74±0.18 °C over the period 1906–20012. Two-thirds of that increase (.6C/1F) has occurred since 1980. [1] This peak represents both the highest global temperature of the past 1000 years and the most rapid escalation. As a kind of shorthand, some scientists refer to the graphed geometry of this peak as a "hockey stick" to evoke a rapid rise after a sustained period of less dramatic change. To the limited degree by which the image of a hockey stick can approximate well-established recent changes in climate, the Hockey Stick is likely correct.I'll leave the body of my argument for Round2 after Con has had his chance, but we need to do some housekeeping regarding our shared assumptions.*****************I take exception to the proffered definition of the Hockey Stick Graph for 3 reasons:1) BIASED- When it comes to defining shared terminology, the offered definition should be as impartial as possible, preferably citing an objective source. Use of the word "infamous" as the first adjective in Con's definition demonstrates significant bias. Here's a definition of the word infamous from Merriam-Webster'sin·fa·mousadjective \G2;in-fə-məs\1: having a reputation of the worst kind : notoriously evil [2]If Con wishes to conclude that the graph is evil during the course of his arguments that's his prerogative. Obviously, we're not going to agree that the graph is evil as part of our common set of assumptions.2) INCOMPLETE- To simply attribute the graph to Mann et. all (MBH99) is to disregard the preponderance of data for which MBH99 is only an initial compilation. Dozens of subsequent studies have confirmed the "hockey stick" geometry to greater or lesser degrees. "Most later temperature reconstructions fall within the error bars of the original hockey stick. Some show far more variability leading up to the 20th century than the hockey stick, but none suggest that it has been warmer at any time in the past 1000 years than in the last part of the 20th century." [3] *3) BURIED THE LEAD- Obviously, the defining element in any Hockey Stick graph is the post-1900 blade- the recent, sharp upturn. The point of the hockey stick is that temperatures have rapidly escalated over the 20th Century and have now achieved the high-water mark for the past millennium. Most hockey stick graphs document significant increases in variability correlating to older data, so the hockey stick has demonstrably less focus on subjects like the Medieval Warming Period (MWP) or the Little Ice Age (LIA) then on periods after recorded thermometer temperatures. To define the graph as primarily a description of the MWP or the LIA is misleading and ignores the central thesis of the hockey stick.We might also note that Con's definition is undermined by the Hockey Stick graph he provides. Con's definition states that the MWP is virtually non-existent and that there's no LIA, but both events are discernible in the Wikipedia graph and conveniently labeled. Therefore, allow me to offer a definition of Hockey Stick Graphs from Wikipedia, which should be more objective and complete than Con's personal definition of Hockey Stick Graphs."Hockey stick graphs present the global or hemispherical mean temperature record of the past 500 to 2000 years as shown by quantitative climate reconstructions based on climate proxy records. These reconstructions have consistently shown a warming in the 20th century with the instrumental temperature record by 2000 exceeding earlier temperatures. The term hockey stick was coined by the climatologist Jerry Mahlman, to describe the pattern shown by the Mann, Bradley & Hughes 1999 (MBH99) reconstruction, envisaging a graph that is relatively flat to 1900 as forming an ice hockey stick's "shaft", followed by a sharp increase corresponding to the "blade". The reconstructions have featured in Intergovernmental Panel on Climate Change (IPCC) reports as evidence of global warming. Arguments over the reconstructions have been taken up by fossil fuel industry funded lobbying groups attempting to cast doubt on climate science." [4]*By way of example, here are a couple of additional graphs that qualify as Hockey Stick Graphs and which reinforce MBH99 data.Here's a graph from the a 2009 New Scientist article comparing 8 later which corroborate 2001 IPCC Hockey Stick (based on MBH99). http://www.newscientist.com...; width="614" height="960" />78 researchers from 24 countries spent seven years compiling data for the PAGES 2K project. They assembled 511 climate archives from around the world, from sediments, ice cores, tree rings, corals, stalagmites, pollen or historical documents and measurements to create the most comprehensive paleoclimate study yet. Published this year in Nature Geosciences, this most recent and comprehensive analysis strongly corroborates the MBH99 Hockey Stick. Green dots are the 30-year average of the new PAGES 2K reconstruction. The red curve shows the global mean temperature. Blue is MBH99 with range of uncertainty. [6] [1] http://www.nap.edu...[2] http://www.merriam-webster.com...[3] http://www.newscientist.com...[4] http://en.wikipedia.org...[5] http://www.newscientist.com...[6] http://www.nature.com...