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European summer weather linked to North Atlantic freshwater anomalies

wcd.copernicus.org

51–60 of 120 posts

Re: European summer weather linked to North Atlantic freshwater anomalies

#51
post #35

Earlier quoted context omitted.

Weather =|= climate. Or one cold day doesn't make winter. Nor does one hot day make summer.

E.g. In Poland this has been the warmest February on record.

Same for Romania, or close to the record, anyway. I don't remember any month of February where we had 20 degrees Celsius in mid-February, and I'm in my 40s.

Re: European summer weather linked to North Atlantic freshwater anomalies

#52

Summary: More ice melt => More fresh water in the Atlantic => cold surface anomalies in winter => sub-polar winter storms => heatwaves in Europe in summer Mostly not predicted as models do not have fine enough grid resolution to show the movement of freshwater into the Atlantic, which happens via "narrow" channels.

Actually, quite a few of this is predicted just not with full certainty. One thing people forget is that Europe is very warm compared to most of Northern America which for the same latitude features much harsher temperatures in the winter.

Most of Northern Europe isn't like most of Siberia or Canada (e.g. Berlin where I live is at the same latitude as Newfoundland. Toronto is almost 9 degrees further south. Winters are mild here, summers quite hot and humid.

The reason for that is the gulf stream which works by hot water flowing towards the arctic, cooling down there and then flowing back. So, we get a lot of hot tropical sea water that keeps things warm. What happens if the arctic water has a lot less ice in it and warms up?

People have of course modeled that and one possible outcome is a mini ice age in Europe. Another possible outcome is accelerated melting of what remains of glaciers and return of some tropical flora and fauna that as evidenced by fossil remains, used to be common in Northern Europe. It all depends. Both have happened in the past. It's hard to predict based on a sample of one. And technically the dumping of epic amounts of CO2 in our atmosphere has not happened at this scale and speed before.

One thing is certain, summers are getting quite toasty in Southern Europe. It's slowly turning more arid, dry, and hot and it isn't that nice of a vacation destination because of it. 32 degrees Celcius is pleasant. 42 degrees just isn't.

Re: European summer weather linked to North Atlantic freshwater anomalies

#54

Summary: More ice melt => More fresh water in the Atlantic => cold surface anomalies in winter => sub-polar winter storms => heatwaves in Europe in summer Mostly not predicted as models do not have fine enough grid resolution to show the movement of freshwater into the Atlantic, which happens via "narrow" channels.

Actually, quite a few of this is predicted just not with full certainty. One thing people forget is that Europe is very warm compared to most of Northern America which for the same latitude features much harsher temperatures in the winter. Most of Northern Europe isn't like most of Siberia or Canada (e.g. Berlin where I live is at the same latitude as Newfoundland. Toronto is almost 9 degrees further south. Winters a…

>The reason for that is the gulf stream

Or, perhaps not:

The Source of Europe's Mild Climate

    The notion that the Gulf Stream is responsible for keeping Europe anomalously warm turns out to be a myth
https://www.americanscientist.org/article/the-source-of-euro...

For context this is mostly from Richard Seager from back in 2002

https://ocp.ldeo.columbia.edu/res/div/ocp/people/seager/

https://www.atmos.washington.edu/~david/Gulf.pdf

and there's still a consensus forming, but he has the chops and he has a point .. there are comparisons to be made to the Pacific North West and being on the trailing edge (spin wise) of a large continental mass.

Re: European summer weather linked to North Atlantic freshwater anomalies

#55

Summary: More ice melt => More fresh water in the Atlantic => cold surface anomalies in winter => sub-polar winter storms => heatwaves in Europe in summer Mostly not predicted as models do not have fine enough grid resolution to show the movement of freshwater into the Atlantic, which happens via "narrow" channels.

That movie The Day After Tomorrow had a really cool visualisation for all that. The movie was released exactly 20 years ago...

Re: European summer weather linked to North Atlantic freshwater anomalies

#56
post #27
post #22

The issue with climate change is exactly that: change. Doesn't matter if it get colder, dryer, wetter, warmer than it used too. It is a huge undertaking to change the built environment to handle conditions that were once seen as exceptional. Houses, streets and waterways are normally replaced/adjusted on the scale of multiple decades or even centuries. Significant climate change is affecting areas everywhere on a sin…

> The natural world doesn't always have the ability to adjust; lots of habits are suffering and species are going extinct. To me this is the much bigger issue than us humans adapting. For us to adapt it demands a lot of labour, and associated costs, it will make life harder but it's doable. Nature doesn't have this ability, animals can't get together in an assembly and find technological fixes to support them living…

Precisely this. Earth's 'normal' extinction rate is often thought to be somewhere between 0.1 and 1 species per 10,000 species per 100 years. A mass extinction event is when species vanish much faster than they are replaced. This is usually defined as about 75% of the world's species being lost in a short period of geological time - less than 2.8 million years.

The current rate of extinction is between 100 and 1,000 times higher than the pre-human background rate of extinction. What we're going through will be an extinction event on a timescale and severity that will be closer to the Permian or Cretaceous extinction, which resulted in the species death of 95% and 78% respectively, and caused by apocalyptic scenarios; meteors and volcanos effectively suffocating the planet. Never before has a single species been responsible for such destruction on Earth.

I suspect humanity will survive whatever future is yet to come. I just hope we managed to preserve a substantial percentage of natural diversity through that process.

Re: European summer weather linked to North Atlantic freshwater anomalies

#58
post #6

Earlier quoted context omitted.

Here in Berlin I’d much rather the traditional 25c summers over the 35c+ summer of ’22 (fortunately ’23 summer was relatively mild and rainy). I do appreciate the mild winters tho!

The mild winters are problem so: - the risk of temp drops after plants started to sprout -> bad harvests - snow is a great water reservoir, having the snow as rain leads to floods, results in lower ground water levels and droughts -> bad across the board and also impacting agriculture - the permafrost in the alps is melting -> mountains litterally fall apart And we see all that already for years now. Edit: As rain go…

That was one hard sentence to parse.

> (the risk (of temp) drops) after (plants started to sprout)

The risk drops, why does it cause bad harvests? Otherwise, what is the "temp"?

The presumably intended reading:

> (the risk of (temp drops))

is nonsensical on a different level: risk always exists. It's the change that's interesting.

Re: European summer weather linked to North Atlantic freshwater anomalies

#59
post #20
post #8

Earlier quoted context omitted.

Buildings in northern Europe are just not built for ventilation, AC and dealing with heat. It’s not a matter of looking, that’s just not how people build here (just like people in Israel don’t build building that handle cold weather well).

> Buildings in northern Europe are just not built for ventilation, AC and dealing with heat. Luckily, because of the cold, buildings are well insulated so at least they can seek some cover inside. Granted, it won't reach 40C anyways, but at least houses are built properly over there so it helps a little.

It doesn't work that way, exactly because the buildings are well insulated they keep warmth for much longer during summer.

Back in July 2018 we had a month of hot weather in Stockholm (you probably experience it, saw in another comment you moved Sweden -> Spain), temperatures reaching 30C for multiple days and "tropical nights" (air temperature >= 20C during the night), even as a native Brazilian I could not bear how hot my house got, it wouldn't cool down during the night and the next day it'd heat up again. It got to a point where I couldn't sleep and there was a shortage of fans for sale, super basic fans were going for 100€ in the 2nd hand market.

Re: European summer weather linked to North Atlantic freshwater anomalies

#60
post #22

The issue with climate change is exactly that: change. Doesn't matter if it get colder, dryer, wetter, warmer than it used too. It is a huge undertaking to change the built environment to handle conditions that were once seen as exceptional. Houses, streets and waterways are normally replaced/adjusted on the scale of multiple decades or even centuries. Significant climate change is affecting areas everywhere on a sin…

This sounds great for GDP!
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