Discover and read the best of Twitter Threads about #PAGES2k
Most recents (3)
Twenty five years ago, on this #EarthDay, Apr 22 1998, the #HockeyStick reconstruction of temperatures was born (nature.com/articles/33859). Here's an interview I did on @CBSEveningNews with @johnrobertsFox (anchor @DanRather):
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The Hockey Stick was extended to the past 1000 years in 1999 (agupubs.onlinelibrary.wiley.com/doi/10.1029/19…) and appeared in it's most recognizable form in the @IPCC_CH 3rd Assessment Report "Summary for Policymakers" (ipcc.ch/site/assets/up…) 
Sorry #DenierBots, the original #HockeyStick was readily reproduced with publicly available data & methods description by other researchers:
link.springer.com/article/10.100…
link.springer.com/article/10.100…
Ăśblicherweise werten wir den Temperaturanstieg seit Beginn systematischer Wetteraufzeichnungen aus:
Häufig werden wir aber auch nach langfristigeren Vergleichen gefragt. Im Projekt #PAGES2k wurden in weltweiter Kooperation Informationen über die Klimaschwankungen der letzten 2000 Jahre zusammengetragen.Dabei wurden Baumringe, Seesedimente, Korallen und Eisbohrkerne ausgewertet.
Mehrere Veröffentlichungen haben dabei wichtige Antworten auf Fragen der Klimaforschung geliefert. Hier wurde beispielsweise untersucht, ob die räumliche Struktur der aktuellen Erwärmung mit anderen Phasen während der letzten 2000 Jahre vergleichbar ist: nature.com/articles/s4158…
1/ documenting questionable incident in #PAGES2K (2017). In respect to Cold Air Cave, South Africa speleothem, they said that they removed "anomalous" period (1956-1976) from calibration since yielded "temperature trends contrary to other published records for last 10,000 years
2/ when checked against original data, PAGES didn't just remove 1956-76 from calibration, they removed it from database and inserted plugged/fabricated data which better matched temperature trends in 20th century - as shown in diagram below.
3/ it's not like this incident overturns EVERYTHING. It's just that it's hard to imagine this sort of opportunistic bodge being done by anyone other than climate scientists. Remember "Briffa bodge"? Early technique to "hide the decline".
