The “hockey stick” debate. Was there a Medieval Warm Period?

In 1999, a bombshell scientific paper was published by three scientists (Mann, Bradley & Hughes). The paper concluded that the 1990s were the hottest decade in at least 1000 years. It became known as the “hockey stick study” and convinced many scientists that recent global warming was unprecedented, human-caused and alarming.Show more

However, in 2003, a group of different scientists (led by Soon and Baliunas) published two scientific papers that came to a very different conclusion. They concluded that there was a similar “Medieval Warm Period” roughly 1000 years ago – long before the Industrial Revolution, in the age of the Vikings, the Maya, the Chinese Tang and Song dynasties, and other Middle-Age cultures. These conclusions by Soon and colleagues led to a lot of outrage and even prompted several editors of one of the journals to resign in mass protest. Wikipedia even has a page dedicated to this controversy: https://en.wikipedia.org/wiki/Soon_and_Baliunas_controversy

But, were Soon and Baliunas right or wrong? Here, Dr. Soon reflects on the controversy and explains why he thinks he was right.

Clip taken from Dr. Willie Soon’s April 11, 2022 talk at Hillsdale College in D.C., “The Weaponization of Science: Politics, Vilification, and the Climate Debate”. For a link to the full talk (1:07:12), see https://vimeo.com/710864737/c408cafffe. Slides for the talk can be downloaded from https://tinyurl.com/48n6tkmw).

Relevant links:
Prof. Mann and colleagues’ famous “hockey stick” study:
🔹 Mann, Bradley & Hughes (1999), "Northern hemisphere temperatures during the past millennium: Inferences, uncertainties, and limitations", Geophysical Research Letters, Vol. 26. https://doi.org/10.1029/1999GL900070
Dr. Soon and colleagues’ studies that disagreed with the hockey stick study:
⭐ Soon & Baliunas (2003), “Proxy climatic and environmental changes of the past 1000 years”, Climate Research, Vol. 23. https://doi.org/10.3354/cr023089
⭐ Soon, Baliunas, Idso, Idso & Legates (2003), “Reconstructing climatic and environmental changes of the past 1000 years: A reappraisal”, Energy & Environment, Vol. 14. Paywalled abstract: https://doi.org/10.1260/095830503765184619; Pdf: https://tinyurl.com/wykk2up4

Prof. Mann and colleagues’ criticism of Dr. Soon and colleagues’ papers:
🔹 Mann et al. (2003), “On past temperatures and anomalous late-20th-century warmth”, Eos, Vol. 84. https://doi.org/10.1029/2003EO270003
Dr. Soon and colleagues’ response:
⭐ Soon, Baliunas & Legates, (2003), “Comment on ‘On past temperatures and anomalous late-20th-century warmth’”, Eos, Vol. 84. https://doi.org/10.1029/2003EO440007

Prof. Storch and colleagues’ criticism of the hockey stick they published shortly after resigning as editor-in-chief of Climate Research:
🔹 Von Storch et al. (2004), “Reconstructing past climate from noisy data”, Science, Vol. 306. Paywalled abstract: https://doi.org/10.1126/science.1096109; Pdf: https://tinyurl.com/2s36r23s

The 2022 study that Dr. Soon mentions near the end of the clip:
🔹 Lüning & Lengsfeld (2022), "How Reliable Are Global Temperature Reconstructions of the Common Era?", Earth, Vol. 3. https://doi.org/10.3390/earth3010024

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🚩 Disclaimer: Some of the scientific opinions expressed in this video disagree with those of the latest UN Intergovernmental Panel on Climate Change (IPCC) reports and several other scientific bodies.

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