Twenty-five years ago, on this day, April 1, 1998, American climate scientist Michael Mann’s paper about temperatures during the last thousand years was released.
http://www.desmog.uk/2015/04/04/how-creation-mann-s-hockey-stick-led-counter-attack-climate-deniers
The amount of carbon dioxide in the air was roughly 368.8ppm. As of 2023 it is 419ppm, but check here for daily measures.
The context was
The Second Assessment Report of the IPCC, released in 1995/6 said that there had already been a discernible impact of human activity on the climate. This enraged the denialists, who were looking for new scientists and science to attack. Michael Mann’s work, which was clearly going to end up in the Third Assessment Report (published in 2001) was one such target.
What I think we can learn from this
Denialists are always looking for targets, and what they perceive to be easy ones – what Mann has since dubbed ‘The Serengeti Strategy’.
What happened next
It properly kicked off, with endless attacks on Mann, lawsuits back and forth. You can read the Wikipedia page here. The science was robust.
What do you think? Does this pass the ‘so what?’ threshold? Have I got facts wrong? Interpretation wrong? Please do comment on this post, unless you are a denialist, obvs..
References
Mann, Michael E.; Bradley, Raymond S.; Hughes, Malcolm K. (1999), “Northern hemisphere temperatures during the past millennium: Inferences, uncertainties, and limitations” (PDF), Geophysical Research Letters, 26 (6): 759–762, Bibcode:1999GeoRL..26..759M, doi:10.1029/1999GL900070
see also