Ireland's weather without jet stream

jonny_b

Just curious as to what our summer would be like if we were not in the jet stream?

Larbre34

Would that not depend largely on whether the stream had migrated to the north or south of us?

Danno

I think the question should be, if Ireland wasn't influenced by the Gulf Stream...

The Jet stream affects everywhere along it's path, The USA, Europe, Asia... and so forth...

Ireland without the Gulf stream would be quite similar to Iceland in winter and our summers would not be much different to current summers.

Pherekydes

I think it's interesting to compare Dublin's climate with a city at a similar latitude that doesn't benefit from a feature like the Gulf Stream, say Punta Arenas in southern Chile. Dublin is 53N and PA is at 53S.

The mean temperature in the three coldest months is 5.3 in Dublin and 1.9 in PA.

The mean temperature in the three warmest months is 14.4 in Dublin and 10.3 in PA.

The mean annual temperature is 9.6 in Dublin and 6.3 in PA.

Interesting, no?

I took the readings from Dublin Airport on the Met Eireann website.

MiNdGaM3

I don't think the gulf stream stopping would have nearly as much of an effect as people think.
We would still be under a westerly influence with the majority of our weather coming off the Atlantic, so it would still be mild. As opposed to somewhere like Labrador which gets its weather from a frozen continent in winter.
I do think that our easterly and northerly winds would become much more potently cold in winter though sea ice extends down to Scandinavia and possibly past Iceland, allowing much less modification of the cold air by the time it reaches us. Cooler waters to out west and north west may also allow for more in the way of cold zonality than usual. But for the majority of the time, we would still have southwesterlies so it would remain mild and wet.

As for the jet stream stopping... I think the jet is in place due to the temperature difference between the tropics and the poles, so I guess removing the jet stream would require either the whole earth to be roasting or frozen over, neither of which would be good!

Elmer Blooker

The Gulf Stream shutting down would probably be the beginning of an ice age, the shallow Northsea would freeze in winter and summers would be very short, eventually snow cover in North West Europe would become permanent as the Arctic ice cap becomes enormous, the N.Hemisphere would then be locked in an ice age.
That's my theory - not that it matters because we wouldn't be around to see it!
The Jet Stream would probably be as far south as the Sahara desert which wouldn't be a desert anymore in an ice age.

Su Campu

It's a hypothetical question. If Ireland didn't have the jet stream then it would be because we wouldn't be at the latitude we are at. We would need to be around 25 ° north or south of our 52-55 °N latitude to be free from its effects. That would mean we'd have a climate similar to say Madeira or Svalbard, respectively. A bit of a difference.

The jet stream is where it is due to the temperature differential between tropical and polar airmasses, which happen to meet around our latitude.

Without the Gulf Stream we would expect a more negative NAO, as the cooler waters north would not support the semi-permanent low in the north Atlantic. We'd be more likely to see Atlantic blocks, especially in summer, meaning a more northerly prevailing component, but also probably more in the way of easterlies as the highs shift eastwards from time to time. So cooler, drier but probably sunnier summers, and more in the way of the cold winters of late.