Kaart Vahrenholt enz.Knipsel













In juni 2006 verklaarde Dr. David Deming, geoloog en geofysicus, voor de ‘U.S. Senate Committee on Environment & Public Works’:

… I am a geologist and geophysicist. … My field of specialization in geophysics is temperature and heat flow. In recent years, I have turned my studies to the history and philosophy of science. In 1995, I published a short paper in the academic journal Science. In that study, I reviewed how borehole temperature data recorded a warming of about one degree Celsius in North America over the last 100 to 150 years. The week the article appeared, I was contacted by a reporter for National Public Radio. He offered to interview me, but only if I would state that the warming was due to human activity. When I refused to do so, he hung up on me.

I had another interesting experience around the time my paper in Science was published. I received an astonishing email from a major researcher in the area of climate change. He said, “We have to get rid of the Medieval Warm Period.”

The Medieval Warm Period (MWP) was a time of unusually warm weather that began around 1000 AD and persisted until a cold period known as the “Little Ice Age” took hold in the 14th century. Warmer climate brought a remarkable flowering of prosperity, knowledge, and art to Europe during the High Middle Ages.

The existence of the MWP had been recognized in the scientific literature for decades. But now it was a major embarrassment to those maintaining that the 20th century warming was truly anomalous. It had to be “gotten rid of.”

… In 1999, Michael Mann and his colleagues published a reconstruction of past temperature in which the MWP simply vanished. This unique estimate became known as the “hockey stick,” because of the shape of the temperature graph.


Normally in science, when you have a novel result that appears to overturn previous work, you have to demonstrate why the earlier work was wrong. But the work of Mann and his colleagues was initially accepted uncritically, even though it contradicted the results of more than 100 previous studies. Other researchers have since reaffirmed that the Medieval Warm Period was both warm and global in its extent.

Lees verder hier.

Vele jaren later, in december 2013, ontving Anthony Watts, webmaster van WUWT, een e-mail van ene ‘Robert’.

Robert says:

The quote is a fabrication. Jonathan Overpeck’s exact words are:

“I get the sense that I’m not the only one who would like to deal a mortal blow to the misuse of supposed warm period terms and myths in the literature.”

Christopher Monckton, like Andrew Montford before him, alters the text to instead read:

“We have to abolish the medieval warm period.”

Anthony Watts is erin gedoken en constateerde dat die informatie juist was, maar dat de gewraakte parafrasering toch spoorde met de essentie van het betrokken citaat.

Lees verder hier.

Reeds vele jaren geleden is ‘CO2 Science’ begonnen met het inventariseren van studies/metingen over de MWP. Het resultaat daarvan is hier te vinden.

In Europa is onlangs ook een soortgelijk project gestart. Onder de titel, ‘New Comprehensive Map By Scientists Confirms Medieval Warm Period Was Real And Global, Climate Models Faulty’, schonk Pierre Gosselin op zijn blog aandacht aan dit project, dat door Fritz Vahrenholt en Thomas Lüning werd geïnitieerd.

One of the biggest obstacles global warming alarmists have had to deal with is the inconvenient existence of the Medieval Warm Period (MWP), as there are reams of literature showing that this period was as warm or even warmer than today.

Yet, a number of global warming activists and alarmist scientists have tried air-brushing away its existence, or claimed it was a only a local North Atlantic phenomenon (just as Wikipedia does).

Now, thanks to the diligence of two German scientists, refuting or denying the existence MWP has just gotten a heck of a lot tougher. In fact from their results it is becoming clearer than ever that the MWP was real and worldwide.

Lüning’s and Vahrenholt’s interactive Medieval Warm Period Map. The period was real and global. Click on the image and the markers to link to the literature underpinning the MWP. On the left side of the map you’ll find the entire list of the literature. The red markers show warm conditions during the MWP, the yellow markers show drought conditions, green markers show wetter conditions and the blue markers show cooling during the MWP. So far there has not been any study indicating a temperature fall!

So far the Medieval Warming Period Map has 157 markers plotted on it. Each plotted marker has an embedded link to the literature which shows the MWP’s existence for that location. As we can see, the 157 studies represented by the markers are scattered all over the globe.

[Vahrenholt and Lüning] …write here that in addition to the dubious efforts aimed at erasing the warm period from history, the climate models have so far been unable to reproduce it. Even the IPCC in its AR5 climate report (IPCC, 2013a, chapter 5.3.5) openly acknowledges the models fail reproduce the MWP warming.

This brings up some crucial questions that Vahrenholt and Lüning pose:

How could it have been as warm as it is today when the CO2 concentration was much lower? Which climate factors were at play back then that are today not adequately accounted for in the climate models? If the models were recalibrated, what results would they show for the future?”

These are tremendously inconvenient questions for the climate modelers and scientists, and so it is not a surprise that some have tried to erase the MWP from history. And these Orwellian white-washing efforts continue today.

Lees verder hier.

Voor mijn eerdere bijdragen over klimaat en aanverwante zaken zie hierhier, hier, hier en hier.