Thread by @MichaelEMann

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…

But more importantly, the #HockeyStick was not only validated, but extended using independent data and methods in subsequent years, leading the @theNASciences (of which I'm now proud to be a member) to subsequently reaffirm our findings: nature.com/articles/44110…

The attacks on the iconic graph by climate change deniers, fossil fuel front groups and their hired guns would nonetheless continue on, leading me to publish "The Hockey Stick & the Climate Wars" (2012; @ColumbiaUP) about my experiences: amazon.com/Hockey-Stick-C…
#HSCW

By 2008, there was a veritable "Hockey League" of reconstructions each of which indicated that global/hemispheric warmth over the past few decades was unprecedented for at last the past millennium and likely longer: pnas.org/doi/10.1073/pn…

Subsequent work by the #PAGES2k team of ~80 scientists around the world using expanded data and refined methods produced the most authoritative reconstruction to date (nature.com/articles/ngeo1…). It was virtually indistinguishable from the #HockeyStick:

The #PAGES2k group would expand and refine their own work, extending the original #HockeyStick conclusion, i.e. the recent warmth is likely unprecedented in at last the past 2000 years: nature.com/articles/sdata…

The @IPCC_CH, in its 2021 6th Assessment report SPM (ipcc.ch/report/ar6/wg1…) would feature an extended version of the #HockeyStick, concluding that "Human influence has warmed the climate at a rate that is unprecedented in at least the last 2000 years" https://t.co/andW6AbO42

Here (from my commentary in @TIME magazine: time.com/6088531/ipcc-c…) is a direct comparison of the #HockeyStick graphs shown in the 2001 @IPCC_CH 3rd assessment report and 2021 6th assessment report Summary for Policymakers (SPM):

Months later, a team of scientists publishing in the same journal (@Nature) that published the original #HockeyStick, would extend it back in time more than 20,000 years, showing that recent warming is likely unprecedented over this much longer time frame: nature.com/articles/s4158

Here's an article I published a couple year ago in @PNAS_news discussing the lessons we can learn from the common era of the past two millennia that go *beyond" the #HockeyStick graph: pnas.org/doi/10.1073/pn…

My next book, "#OurFragileMoment: How Lessons from Earth's Past Can Help Us Survive the Climate Crisis" (due out later this year from @public_affairs/@HachetteBooks) is about the lessons we can draw from past climate history writ large: hachettebookgroup.com/titles/michael…

And finally, here's my good friend @BillNye reminding us that the #HockeyStick and its important message for us, both still live on: msnbc.com/velshi-ruhle/w…