Low lying clouds off Dublin coast

jrd · 03-02-2015 10:34pm #1

Something from left field here. I do a bit of photography - seascapes etc. A bunch of us who do sunrise shoots have noticed that on every sunrise that we can remember for the last month, there has been a bank of low cloud on the horizon. It seems not to affect Laytown and beyond to north. The first couple of times we saw it, we put it down to bad luck. However, we've seen it at least 6/7 times over the 4 weekends. Shooting off Great South Wall or Bull Wall almost pointless now. The upshot is that we will be travelling north or south of Dublin in future. Anyone else notice this and could there be any logical explanation of this? Thanks.

Kermit.de.frog · 03-02-2015 11:37pm

Must be either sea fog or cloud in the distance on the Irish sea.

jrd · 04-02-2015 9:01am

Thanks for the reply. It's the oddest thing as the cloud is about the same height every single time and a blank sky above.

weatherfiend · 04-02-2015 12:00pm

Do you mean like this? This photo taken from further inland but looking out over Dublin bay and we have been commenting on it every morning for the last week or so.

Calibos · 04-02-2015 12:09pm

Streamers I would have thought.

weatherfiend · 04-02-2015 12:17pm

Yeah I wondered was it that. It certainly looked fab (better in real life). Didn't appear to be any precip from it

Nabber · 04-02-2015 3:47pm

By your description it sounds like streamers.

But over a month, by this you mean 4 calenar weeks?
The streamers only began when the wind direcriin turned to northerly.

For most of the past month we have gone west or north west.

Can you confirm dates.

Also, you are a photographer. Post a picture of them and you will get the answer you need

Zack Morris · 04-02-2015 4:31pm

If you're a photographer, why didn't you post a picture?

VeVeX · 04-02-2015 4:44pm

Zack Morris wrote: »

If you're a photographer, why didn't you post a picture?

Just thinking that as I read down the thread.

Calibos · 04-02-2015 5:24pm

Nabber wrote: »

By your description it sounds like streamers.

But over a month, by this you mean 4 calenar weeks?
The streamers only began when the wind direcriin turned to northerly.

For most of the past month we have gone west or north west.

Can you confirm dates.

Also, you are a photographer. Post a picture of them and you will get the answer you need

The streamers don't have to have been aimed and traveling towards the east coast in a North easterly though. They could be forming off Meath and Louth and pointing and traveling towards Wales in a North Westerly which is the Wind direction we've had for a lot of the last month. From ones perspective on the East coast it'd still look like a straight line of cloud along the horizon out to sea if you get me.

dirtyghettokid · 06-02-2015 10:40am

yea i get that all the time! kind of annoying. the sun never comes up straight off the sea.. there's always clouds off in the distance (at least i think that's what you're referring to?) i live in north county dublin and 9 times out of 10 will always see clouds on the horizon

2nd december sunrise by dgk905, on Flickr

golden lining by dgk905, on Flickr

east coast morning by dgk905, on Flickr

moments like these by dgk905, on Flickr

nevitt morning by dgk905, on Flickr

Popoutman · 09-02-2015 11:33pm

A lot of this is a function of geometry. The closer to the horizon you look, the more atmosphere you are looking through.

If there's cirrus clouds at e.g. 30,000 feet, but at the horizon, they are somewhere in the region of 150 miles away. It's quite rare at these latitudes anyway to have 150 miles or more without some form of higher cloud.

Even cumulus at 10,000 feet would be visible out to 50 miles away, over Wales from Dublin.

To have a clean sunrise or sunset, you'd need quite a long path of cloud-free air, probably a *lot* longer than most people realise.

(I know my mathematics are approximate, but I'm not too far off.)

prosaic · 10-02-2015 12:45pm

I think you'd be able to see clouds out to 250km or something like that. Transponders on planes seem to work out to that range, maybe even to 300km. They fly aboout 10 or 11km altitutde. The horizon cuts off the signal at that range.
In the pics above, the clouds visible are at various distances. some are only 30 km away. Perspective compresses apparent distances near the horizon. If you hold your thumb out horizontally with one side on the horizon and if there were two objects at the same altitude with one appearing around the top edge of your thumb and the other appearing at half the width of your thumb above the horizon, the second object would be something like twice as far away as the first object.
Then for higher accuracy, you need to account for earth curvature and the bending of light through the atmoshere. An example of light bending is seen when the sun is at the horizon. It gets squased flat due to the bending. The bending is variable and depends on the temperature/pressure/humidity profile in the atmosphere. I think the effect here is small enough.
You could use a satelite image around the time of viewing to see where the clouds are. The welsh coast is only 100km away from Dublin so coulds there easily seen. You might be able to see high clouds over Liverpool.

Low lying clouds off Dublin coast

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