Some Notable Hockey Stick Reconstructions

 For fun I've been collecting hockey sticks. The following are not complete, but I think they're pretty representative. In fact, I even collected the much maligned Loehle 2008 reconstruction, which has been the darling of contrarian "science." There are numerous issues with that reconstruction, which I document here, but I'm including it because doing so doesn't change the fact that all known temperature reconstructions covering anywhere from NH-extratropical temperatures to global mean temperatures have a hockey stick shape if you include the 21st century.

I decided to break this up into three graphs, one showing GMST reconstructions, one showing NH and NH-extratropical reconstructions, and one showing NH-summer and/or NH-growing season reconstructions. I'm showing each with their respective instrumental counterparts (global, NH, and NH-summer). For reconstructions with annual resolution, those are shown faded, but I show running 10-year means for all of them except Loehle 2008. That paper was only able to reconstruct 29-year running means. I show the 95% confidence interval for Pages 2K in the global reconstruction, but I didn't show any confidence intervals in the other graphs because I thought they looked a little too cluttered. For the graph of GMST anomalies, all of the reconstructions show temperatures within the confidence intervals of Pages 2K.

GMST Anomalies

NHMST Anomalies

NHMST Summer or Growing Season Anomalies

Here are a couple more reconstructions that cover the Holocene. The top graph is "proxy only" reconstructions with a combination of Shakun 2012 and Marcott 2013 that I found in Clark et al 2016 and Temperature 12K with HadCRUT5. I plotted the two-sigma confidence intervals so you can see that the median reconstruction for Temperature 12K (mostly) fits within that CI.
GMST Anomalies


The above proxy only reconstructions differ from data assimilation (reanalysis) approaches in the warmth of the HTM. DA products tend to have the HTM much cooler than proxy-only reconstructions. This may indicate a seasonal bias affecting proxy-only reconstructions that make these reconstructions follow obliquity too closely. The graph below comes from Erb et al 2022.


This is a total of 19 reconstructions. I'll add more as I find them, but I don't know of any reconstructions that don't have hockey stick shapes when including temperatures from about 1990 on. Each of these are also plotted against the 1850-1900 mean, so they should provide a good indication of how much warmer we are than preindustrial levels


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