http://news.bbc.co.uk/1/hi/world/europe/8550025.stm?ls

What exactly caused these waves in the Mediterranean Sea?

Keith (Southend)

On 5 Mar, 11:54, "Keith (Southend)G"
wrote:
http://news.bbc.co.uk/1/hi/world/europe/8550025.stm?ls

What exactly caused these waves in the Mediterranean Sea?

They occurred the day the low on the west of Iberia became the low on
the east of Iberia.

And of course you know from following the incomparably wonderful
Weatherlawyer that the low was linked to that earthquake that had been
so upsetting for everyone uik.sci.weather for the last month or so?

Note to .....

Tsunamii were called tidal waves because they are tidal. It is only
recently the badly informed have learned to think of them in terms of
height instead of volume.

Is plura plural of plural?
Bthaght! Try saying that after a plate of cauliflower cheese.

On 5 Mar, 12:30, Weatherlawyer wrote:
On 5 Mar, 11:54, "Keith (Southend)G"
wrote:

http://news.bbc.co.uk/1/hi/world/europe/8550025.stm?ls

What exactly caused these waves in the Mediterranean Sea?

They occurred the day the low on the west of Iberia became the low on
the east of Iberia.

And of course you know from following the incomparably wonderful
Weatherlawyer that the low was linked to that earthquake that had been
so upsetting for everyone uik.sci.weather for the last month or so?

Note to .....

Tsunamii were called tidal waves because they are tidal. It is only
recently the badly informed have learned to think of them in terms of
height instead of volume.

Is plura plural of plural?
Bthaght! Try saying that after a plate of cauliflower cheese.

So it was the weather, not a Tsunamii cause by an earthquake?

Thanks

Keith (Southend)

On 5 Mar, 13:05, "Keith (Southend)G"
wrote:
On 5 Mar, 12:30, Weatherlawyer wrote:
On 5 Mar, 11:54, "Keith (Southend)G"
wrote:

http://news.bbc.co.uk/1/hi/world/europe/8550025.stm?ls

What exactly caused these waves in the Mediterranean Sea?

They occurred the day the low on the west of Iberia became the low on
the east of Iberia.

And of course you know from following the incomparably wonderful
Weatherlawyer that the low was linked to that earthquake that had been
so upsetting for everyone uik.sci.weather for the last month or so?

Note to .....

Tsunamii were called tidal waves because they are tidal. It is only
recently the badly informed have learned to think of them in terms of
height instead of volume.

So it was the weather, not a Tsunamii cause by an earthquake?

No it was probably a local problem where chains of swell meet. Look up
Newton's Rings

http://en.wikipedia.org/wiki/Newton's_rings

These trains crossing each other produce double low troughs as well as
double high crests. So if the ship went into a trough before hitting a
large wave it would have been inundated with the first.

It was probably designed to withstand one of them but then it hit 2
more of each.
Probably.

Just my take.
But if all those decks were loaded by the first hit, the hydraulic
pressure would have been much greater. Without stabilisers it would
have been a gonner.

Lots of bulk carriers used to go in the good old days. Lost without
trace. They used to blame welding. (Liberty boats of the 1940's had a
welding problem until they understood about radial corners.)

Odd that it was just bulk carriers not tankers. But tankers only use a
few well known routes. I suppose we'll never know until they start
finding them for Channel 5.

"Weatherlawyer" wrote in message
...
On 5 Mar, 13:05, "Keith (Southend)G"
wrote:
On 5 Mar, 12:30, Weatherlawyer wrote:
On 5 Mar, 11:54, "Keith (Southend)G"
wrote:

http://news.bbc.co.uk/1/hi/world/europe/8550025.stm?ls

What exactly caused these waves in the Mediterranean Sea?

They occurred the day the low on the west of Iberia became the low on
the east of Iberia.

And of course you know from following the incomparably wonderful
Weatherlawyer that the low was linked to that earthquake that had been
so upsetting for everyone uik.sci.weather for the last month or so?

Note to .....

Tsunamii were called tidal waves because they are tidal. It is only
recently the badly informed have learned to think of them in terms of
height instead of volume.

So it was the weather, not a Tsunamii cause by an earthquake?

No it was probably a local problem where chains of swell meet. Look up
Newton's Rings

http://en.wikipedia.org/wiki/Newton's_rings

These trains crossing each other produce double low troughs as well as
double high crests. So if the ship went into a trough before hitting a
large wave it would have been inundated with the first.

It was probably designed to withstand one of them but then it hit 2
more of each.
Probably.

Just my take.
But if all those decks were loaded by the first hit, the hydraulic
pressure would have been much greater. Without stabilisers it would
have been a gonner.

Lots of bulk carriers used to go in the good old days. Lost without
trace. They used to blame welding. (Liberty boats of the 1940's had a
welding problem until they understood about radial corners.)

Odd that it was just bulk carriers not tankers. But tankers only use a
few well known routes. I suppose we'll never know until they start
finding them for Channel 5.



When that wave hit the ship-did the earth move for you?

in 237590 20100305 123007 Weatherlawyer wrote:

Tsunamii were called tidal waves because they are tidal.

Huh?. Nothing to do with tides.

"Bob Martin" wrote in message
...
in 237590 20100305 123007 Weatherlawyer wrote:

Tsunamii were called tidal waves because they are tidal.

Huh?. Nothing to do with tides.


Yes beware the tides of March

On Fri, 05 Mar 2010 17:35:23 GMT, Bob Martin wrote:

Tsunamii were called tidal waves because they are tidal.

Huh?. Nothing to do with tides.

Tidal as in the whole body of water moving, not just the top like a
normal "swell type" wave. Think of a tsunamii as a "tide" that goes
out and in over a matter of minutes rather than hours.

--
Cheers Dave.
Nr Garrigill, Cumbria. 421m ASL.

Keith (Southend)G wrote:

http://news.bbc.co.uk/1/hi/world/europe/8550025.stm?ls

What exactly caused these waves in the Mediterranean Sea?

Keith (Southend)


The wind? :-)

--
Norman Lynagh
Tideswell, Derbyshire
303m a.s.l.

"Norman" wrote in message
...
| Keith (Southend)G wrote:
|
| http://news.bbc.co.uk/1/hi/world/europe/8550025.stm?ls
|
| What exactly caused these waves in the Mediterranean Sea?
|
| Keith (Southend)
|
|
| The wind? :-)
|

There was a very good documentary on this subject in the "Horizon" series a
few years back. The whole idea of these "freak" waves was discounted,
mostly by vested interests who would have had to pay more to properly design
and maintain ships, until study showed that they undoubtedly occur.

Waves can interact in various ways with each other, and also with currents
generated by tides or the overall circulation of the oceans. Under certain
circumstances energy in the general wave field can be concentrated in a few
individual members of a wave train resulting in these unexpectedly large
waves. The phenomenon is rare enough to not be obvious to those with
passing business on the seas, but not so rare that occasional incidents -
such as that reported - do not occur. Many of the allegedly "unexplained"
disappearances in the open seas are probably due to ships encountering these
"freak" waves.

When the maths and physics was done it was found that the likelihood of this
concentration of energy in individual waves increased rapidly with the
overall wave height. So under normal sea conditions one would not expect to
notice any unusual waves, but in stormy conditions they become much more
likely. The risk is also greater in areas where strong currents run, which
can also contribute energy to the waves.

So, although the energy these waves contain did come from the wind, the
waves were higher than the observed windspeed would be expected to produce
because they have "borrowed" energy from other waves in the sea around (this
is the "non-linear interaction" you will hear described in the documentary
mentioned). The cruise ship was therefore also a victim of what is best
described as "bad luck".
--
- Yokel -

"Yokel" posts via a spam-trap account which is not read.