Loehle (2007)

What happens if you do a climate reconstruction without using tree rings? You don’t have as much data, but the result is:

Loehle, C. 2007. A 2000-year global temperature reconstruction based on non-treering proxies. Energy & Environment 18(7-8): 1049-1058.

Abstract:

Historical data provide a baseline for judging how anomalous recent temperature changes are and for assessing the degree to which organisms are likely to be adversely affected by current or future warming. Climate histories are commonly reconstructed from a variety of sources, including ice cores, tree rings, and sediment. Tree-ring data, being the most abundant for recent centuries, tend to dominate reconstructions. There are reasons to believe that tree ring data may not properly capture long-term climate changes. In this study, eighteen 2000-year-long series were obtained that were not based on tree ring data. Data in each series were smoothed with a 30-year running mean. All data were then converted to anomalies by subtracting the mean of each series from that series. The overall mean series was then computed by simple averaging. The mean time series shows quite coherent structure. The mean series shows the Medieval Warm Period (MWP) and Little Ice Age (LIA) quite clearly, with the MWP being approximately 0.3°C warmer than 20th century values at these eighteen sites.

Article available here.

Craig Loehle Reconstruction, where it all began!

Loehle Proxies lists the proxies used in Loehle.

Loehle and Moberg compares Loehle proxies with Moberg's low frequency network and finds quite a bit in common.

Emile-Geay and Verification r2 Statistics discusses the lack of R-squared statistics in various papers, including Loehle (2007).

Craig Loehle Reconstruction #2 continues Craig Loehle Reconstruction discussion.

Loehle Proxies #2 lists the proxies used in Loehle with more details.

Steve says "To my knowledge, Loehle’s network is the first network to be constructed using series in which every proxy as input to the network has already been calibrated to temperature in a peer reviewed article. This is pretty amazing when you think about it. It’s actually breathtaking. Every prior network has included some, if not a majority, of uncalibrated proxies." in Something New in the Loehle Network

The Loehle Network plus Moberg Trees adds Moberg's tree proxies to Loehle's larger non tree network and gets a stronger MWP than Moberg did.

MBH98-Style Pseudo-Confidence Intervals for Loehle adds MBH98 style error bars (considered to be worthless) to Loehle's results.

Loehle Proxy MD95-2011 looks at an individual proxy from Loehle's network in detail.

realclimate on Loehle discusses realclimate's review of Loehle (2007) concluding with "(realclimate's) comments on multivariate methodology appear weak to me, but the comments on individual proxies are well worth reading. ... surely apply equally or even more so to Moberg."

Loehle Correction points to Loehle's Correction, which consists of some minor fixes.

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