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It was warmer at that time than now.

https://www.sciencedirect.com/topics/earth-and-planetary-sci...

The medieval warm period coincides with the viking expansion and contraction.

Edit: see response, below

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I don't think much of that article. It appears to be from a climate heating-denialist book and has a number of errors.

If you look at the Wikipedia page on the subject: https://en.wikipedia.org/wiki/Medieval_Warm_Period ...it shows that the medieval warm period was not a global phenomenon.

It also contains comical unchecked claims such as "During the Medieval Warm Period, wine grapes were grown as far north as England, where growing grapes is now not feasible". This is blatantly false, as there is a wine industry in England. With summers getting increasingly warm, recent decades have even seen the development of Welsh wines.

Edit: actually it seems to be a selection of articles from different sources, but prominence is given to "Evidence-Based Climate Science", an obscure book, for some reason.

The claim wine grapes were cultivated in England during the MAs (without the aid of technology) is an old claim and predates the politicization of climate change.
That's not a controversial claim.

The controversial bit is that wine grapes cannot be grown in England today. They can grow and are grown today.

And back into the 1980s at least, to my personal knowledge. I’ve had a grape vine growing on the side of my shed here in South London for the last 7 years.
Grape vines have been grown since forever in the UK. They do fine. They are all over london. What's not easily doable is getting ripe fruit off them (fruit, yes, little green bullets, ripe... much harder). I don't know how it's done commercially currantly[0].

One planted in 1769 is still around. I assume it's under glass. Saw it when I was a kid (https://en.wikipedia.org/wiki/Hampton_Court_Palace)

[0] thank you, thank you

Edit: a bit more on that ancient and huge vine https://www.atlasobscura.com/places/the-great-vine-east-mole...

I believe that our climate is warming. I've seen it with my own eyes on trips to Alaska, Nova Scotia and Alberta. Having said that, Europe did go through a little ice age, the end of which opened up shipping routes for the Vikings. I also know from many sources that winemaking existed in Scandanavia before this little ice age, and now has returned to that region.

This may be the case: global warming is happening everywhere, but it's more pronounced in the North. And melting icebergs and glaciers make for better PR than say one degree warmer temperatures in the deserts of Saudi Arabia.

The medieval warm period is basic history.

I just picked a random site that talked about it.

As for the wine in England:

https://www.nytimes.com/interactive/2019/10/14/dining/drinks...

> Places, like England, that were historically unsuited for producing fine wine have been given the opportunity to join the global wine world, transforming local economies in the process.

As many college students can attest, there's plenty of wine which is not "fine wine".
never drink french red wine sold in bottled water style containers in France unless you have a very robust digestive system. I spent a couple of days in a fetal position after a bender on that stuff...
The medieval warm period was most definitely a climate phenomenon with global ramifications though. Seeing as the coast of England was completely different. The higher water levels allowed the vikings to bring their ships much further inland than would be possible today.
Not to be pedantic but Welsh wines are not exemplary of an English wine industry.

That being said, UK wine production is more of a curiosity than an industry. Domestic wine represents 1% of U.K. wine consumption, and they U.K. doesn’t make the top 25 of wine producing nations.

I believe the climate started getting colder and more variable in the 14th century, which unfortunately also coincides with the arrival of the Bubonic plague. Similar events also happened with the arrival of the bubonic plague during the reign of Justinian of the Roman Empire. It's probably responsible for bringing on what we think of the Middle Ages vs. the Late Antique. If anyone is interseted, there is a great podcast called "Tides Of History" The author goes into great detail about each period.
Thank you for the podcast recommendation.
They're finding tons of old stuff here in Norway these days, even random people hiking in the mountain stumble over 1250 year old viking swords[1], spears, arrows. Skis from the year 700 AD.. etc..

Lots of it gets documented by the Secrets of the Ice project[2].

[1]: https://i.pinimg.com/originals/1b/25/3f/1b253f39890eaac465f6... [2]: https://secretsoftheice.com

Are more people going to more remote locations, I wonder? Or are people reporting their findings more now because of the internet?
The Internet has been ubiquitous for a couple decades, and most of Norway is "remote location" where trekking been always popular. So, no.
Global warming is melting away the glaciers.
This article from national geographics[1] explains it well I think. Objects were lost in the snow by travellers crossing the mountains up to 2000 years ago, over time they got covered in stationary ice (glaciers move and crush items).

Now these stationary ice pockets (and glaciers) are slowly melting, leaving well preserved lost items from the old days in its place.

[1]: https://www.nationalgeographic.com/history/2020/04/lost-viki...

I thought now it is the warmest it has ever been since human civilization began.
MWP was about +1 C more, while the PETM was about +15 C more than global average temperature as of now.
AFAIK, humankind flourished during the medieval ages (minus plagues and modern medicine and war). But, at least nothing obviously climate related. I wonder why we would have more trouble nowadays with even more advantages.
A) the lower bounds of climate change is now +2°C. The MWP was maybe +1°C.

B) (Possibly) I can't tell how long that change took to come into effect. One of the current concerns is how rapidly climate is changing.

C) Evidence points that the MWP only affected areas around the North Atlantic. Current climate change is having impact globally (though not equally so everywhere)

There were a ton of societal disruptions in the period of 950-1250. Vikings, Normal conquest of England, the Crusades. I'm not making an argument that any of those were caused by changing climate, but it definitely was a time of change with a heavy admixture of violence.

>One of the current concerns is how rapidly climate is changing.

Isn't there also concerns about methane in permafrost also amplifying the warming? Wouldn't that dispel the notion that it hasn't changed this rapidly before?

Yeah there are concerns about methane being released from melting permafrost. I can't find information about how old the permafrost is - but my understanding is tens of thousands of years old. I also can't tell if the methane itself is old, or if the methane just forms rapidly with all this newly thawed rotting vegetation.

https://www.vox.com/2017/9/6/16062174/permafrost-melting

There's evidence of times in the distant past where climate has changed very quickly, but all those predate history. There are some that even predate humanity. Here's an interesting one from ~12k years ago:

https://en.wikipedia.org/wiki/Younger_Dryas

20 megatonnes/year is small potatoes compared to methane hydrates' 1-5 teratonnes storage that could go within a decade. There is at most 1.5 teratonnes of methane in arctic permafrost, but that will take much longer to release (50-100 years at a very conservative minimum) and it will degrade with a 7 year half-life.
Yes, the methane gun hypothesis. In modern times, there is an ever-growing risk of immense methane clathrates in the ESAS destabilizing and suddenly boiling off more than they already are. Methane has a GWP of ~1000x CO2 immediately, but it tends to dissipate within ~60 years with a half-life of roughly 7 years.

I would watch some videos on YouTube by Paul Beckwith and Natalia Shakhova about this topic. They are regular COP panel speakers. Natalia has been ringing scientific alarm-bells about methane hydrates since at least 2010, but not enough of the human family has listened yet.

https://www.youtube.com/user/PaulHBeckwith

https://www.youtube.com/results?search_query=natalia+shakhov...

So the rate of change isn't really an issue at all then?
The PETM was a long time before human civilization began.
And the MWP did not cause the entire Earth to warm, so, here we have yet another green username sounding authoritative but being a bit wrong.