Atmospheric Conditions No Moon and Refracted Images


Dec 2, 2000
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Alright, here goes another crazy question. Some have stated that it was a moonless night. Some have said that the Moonless night coupled with the atmospheric conditions from the ice, air and what not that there was a distinct possibility that things could have been see at greater distances that night due to refraction. What are your ideas and comments on this? And also, would this condition also make it possible to see things as if magnified making them clearer?
Would it noticebaly change the hue or distort the size or position of any light?
Maureen.
 
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Andrew Rogers

Guest
Hi Maureen.
Black is black.
The way I see it, unless there was light nothing was going to make a burg more visible.
As a kid I spent many nights out on my uncle's sheep station in outback Australia and a moonless clear night was very common but it was impossible to see ANYTHING. I think the absence of man made light in the middle of the Nth Atlantic might be similar to a sheep station on the NSW/Queensland border! (the driveway on his property was 2 kms long!)
I tend to believe that lookouts, George Symons and Reg Lee where closer to the money when they claimed to be able to "smell ice before you get to it". Not that it worked too well for old Reggie.
I have never been able smell an iceburg but I think it would be easier than trying to see one on a pitch black night.(actually I have never even seen an iceburg)
Sorry Maureen, I know this is very blunt and non-scientific but I think it's true.
Bye for now,
Andrew.
 

Martin Pirrie

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Dec 30, 2000
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Maureen, I am going to try to answer your questions. In The Mariner’s Handbook published by The Hydrographer of the Navy (British) there are five or so paragraphs about a phenomenon titled Abnormal Refraction. Just as on land on a hot day when one looks down a tarmac road, one can see a mirage. So at sea, with certain weather conditions, it is possible to see something similar. The propagation of light depends upon the temperature and density of air. Usually as one goes higher the air becomes colder. Occasionally, the reverse happens. This is known as an inversion. Fog can form at the junction of the upper layer of warm air and the cold air. The inversion layer can be anything from a few feet above ground upwards.

There is also something called super-refraction. Super-refraction occurs when the rate of fall of temperature with height is less than normal or when the relative humidity decreases with height. When these conditions are combined with an inversion layer the effect is more pronounced. One of the weather conditions where the Handbook states this could occur is: “In high latitudes where the sea surface temperature is exceptionally low.”￾ Super-refraction increases the optical horizon so that it is possible to see objects which are beyond the physical horizon.

As light is only one form of electro-magnetic radiation, these refraction effects can be detected with radio and radar signals too.

Martin Pirrie.
 
Dec 2, 2000
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Okay, I am saying this on this board Martin...I love you! That is the information that I have been looking for! i am so excited!!!!

Okay bear with me for a minute. Based on the infomration that Martin provided, would it be possible to "gauge a distance" inaccurately based on how far away something is in percentages.

Like if the bend in the horizon should technically make it impossible for me to see a boat/ship unless it was A distance from me, but I see it due to super-refraction. Then as a trained sea captain if I were seeing a boat/ship between me and the horison and I "knew" that I could only see X miles (whoich is equal to A distance) and the ship looked to be about 2/3 of that distance (2/3A). Wouldn't I assume that the ship was (2/3 A) and closer than it really was. When in fact it was A+ the additional refracted idstance allowed due to the super refracted conditions).

Am I making sense to any body out there?

But it is critical to understand that this atmospheric phoenomenon is only happening to my ship, the other ship may be in perfectly normal atmosphere and due to the A+ extra distance) doesn't even see me because I am over his horizon.

Martin? Anybody?

(Thanks so much Martin for that information!!!! oooh now I have goosebumps!)
Maureen.
 

Martin Pirrie

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Dec 30, 2000
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Maureen, I’ve never given an American lady (or any lady come to think of it) goosebumps before! You’ve made a young (ish) man very happy! Thank you!

Please don’t get too excited about super-refraction. It exists but how one measures the real and apparent distances, I do not know. With radar, one gets to recognize the spurious images on the screen. They don’t look “right”￾: they can fade away too quickly to be a physical object.

I believe that you may be heading off into another ice field! If you are thinking of a ship, named Californian then there is much physical evidence to counter any thoughts of
super-refraction. For instance, Californian crossed the ice pack to meet up with Mount Temple and then re-crossed the ice pack to meet Carpathia. Even taking into account that it was daylight, the time taken for the first traverse would put Californian a little less than 10 miles away from Titanic. If Californian was beyond the physical horizon, then she would have had to drift about 10 miles from the time that Titanic sank to the time that Californian moved off towards Mount Temple.

I was a pro-Lordite, if only to protect the underdog. But now I believe that Capt. Lord just didn’t take enough notice of his crew and they, in turn, were not forceful enough in their reports. I have done it myself once. I convinced myself that I was looking at one thing and when someone went back the next day, I was proved to be completely wrong. I lost my job.

Martin Pirrie.
 
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Andrew Rogers

Guest
Sorry Maureen, I have iceburgs on the brain.
I misunderstood the question.
Andrew.
 
Dec 2, 2000
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First Andrew. Balck is black and so was my brain when it asked the question....or it was refracted maybe he he...anyway no problem Andrew. I thought what you wrote was very interesting though.

Now to Martin. Hey, you young guys can do that goosebump thing anytime. I floated all day at work cause I got some great information that I was looking for.

And no, I was not trying to support anything to do with the Californian at all. Just trying to learn something that's all about the sea and how it can play games with even the most avid seaman. That's all.

I do not know enough about the Californian to say that was pro, con or medium luke warm on teh topic of Capt Lord. So, wrong motive Mr Mason (perry that is).

Glad to have provided your first goosebump giving experience...wait are you of age?
Maureen
 

Martin Pirrie

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Dec 30, 2000
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Maureen, if you e-mail me on [email protected] I’ll send you the complete notes from the Handbook I mentioned.

The effects of refraction are most noticeable at higher frequencies hence that is why radar shows up so many. I have a distinct feeling that many UFO sightings are refraction effects in the upper atmosphere. Images of earthly objects or parts of objects hanging in space. That’s why these images can move so quickly and vanish in a flash! They were not there to start with! When the pocket of air moves, so does the image!

I have seen pictures in old books of sailors seeing ships floating in air or even upside down just above the horizon. Refraction again. I wonder if the sails made the images more visible? I have never seen refraction at sea with the naked eye. On a radar screen, often. There has been a report in the newspapers in UK last week of the Falklands war in 1982 and the disastrous result of refraction effects when incoming hostile aircraft where ignored because the day before there had been so many “bogeys”￾ (false reports).

The Capt. Lord effect again?

Martin Pirrie
 
Dec 2, 2000
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As I sat in my car last night looking at an incredible Friday the thirteenth full moon fully refracted on the horizon to a big like greater than sun size, I thought about this thread again.

Would refraction cause the stars to be more difficult to chart and navigate from, due to false readings of star locations where there shouldn;t be any. Also, was this topic a readily known fact at the time of Titanic or is this something that was identified later?

Would the recent 1910 citing of Halley's comet also have made them more "falling star" prone as well? For those with experience on the sea, that must have been a tremendous sight.
Maureen.
 

Martin Pirrie

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Dec 30, 2000
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The phenomenon of refraction has been known to sailors for many years, most certainly before Titanic. Images of sailing ships mysteriously floating upside down above the horizon are shown in 17th century sailing books.

But how refraction affects stars (if it does) and how navigation is affected - I cannot say. Any sailors out there should be able to give a definitive answer.

Martin Pirrie.
 
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Dragos Dumitru

Guest
Hello, I am quite new around here but I have read some of the discussions here and I have found them very challenging.
I was wondering if there is anyone who could explain to me WHY did the two lookouts not see the iceberg EARLIER, I mean from a greater distance, so that the ship could have had enough time to manoeuvre and avoid the impact...?
Was it because it was night and dark or because they were not paying attention ?
This problem of spotting the iceberg on time haunts me for a long time and I just cannot understand. If someone could give me an answer I would be very grateful.

Best wishes,
Dragos
 
Dec 2, 2000
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Easley South Carolina
Dragos, it would have to depend on conditions. David Brown offered the proposition that the lookouts may have been looking at it for quite some time, but as a black spot in the sea haze illuminated ever so faintly by the starlight. What they thought was an opening in the icefeild was a roadblock! I have some doubts about this but it's plausible.

Absent that, remember, it was night time and as dark as it gets at sea...especially on a moonless night...it's very difficult to see much of anything at long range unless it's illuminated by something like moonlight, or showing lights such as what another ship would do.

One other possible factor to consider is that the berg may have rolled over because of meltoff changing it's balance. Had this happened, instead of a white frost on the surface to reflect what little light there was, you would have a dark surface which would reflect little at all. Toss that in and the lack of breakers as Tracy pointed out, and you wouldn't see anything until you were almost right on top of it.

Cordially,
Michael H. Standart
 
Dec 4, 2000
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Dragos--

Forgive me for asking you to read my book for a full version of my theory. It's not that I want you or anyone to spend money, but this isn't the place for a wordy manuscript.

It was not a "dark" night. It was a clear night with full starshine. Dark-adapted eyes would have seen much more at sea than someone living in a city would believe. No reading of newspapers, but still the stars put out a lot of light.

However, it was a cold night just before bad weather (experienced by Carpathia enroute New York). I have often noted that a mirage called "towering" is common at such times. It is caused by atmospheric conditions.

"Ice blink" is another optical illusion seen only in arctic areas that also requires similar atmospheric conditions. Ice blink is light reflected off thin fog common over large patches of ice.

Curiously, both of these phenomena were recorded by Californian at 1021 when that ship ran into the same field of ice that claimed Titanic. These optical illusions may also explain why Californian spotted Titanic so much earlier than Titanic noted Californian.

I theorize that these two phenomena combined to form an optical illuison on the horizon that the lookouts described as "haze." The iceberg was in front of the field of ice, so appeared as a dark spot in the haze. As Fleet described its first appearance, "a dark mass."

With a nod toward George Behe, I believe the lookouts and Murdoch both saw the dark spot against the haze. In other words, the mis-perceived the truth until Titanic was up on the berg. However, from Fleet's testimony and later conversations with other authors, I believe that the "dark mass" was spotted and reported to the bridge up to 8 minutes prior to the accident.

Based on what the rescue ships reported at first light, Titanic had to have been dodging ice for some time prior to the accident. (Remember Rostron's dash in Carpathia.) My supposition is that Murdoch correctly realized there was field ice ahead, but took the dark spot to be an opening. This would have been an easy mistake for someone who had been looking for dark water around the lighter shapes of floating ice all during his watch. So, Titanic was steered straight at the iceberg until that sudden realization..."Iceberg Right Ahead!"

--David G. Brown
 

Mike Herbold

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Feb 13, 2001
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David:
Very interesting comment about the crew of Californian possibly seeing the Titanic much earlier than the Titanic saw the Californian because of the ice blink. I have spent some time in the Arctic and can vouch for what you say. I probably have an exaggerated remembrance of it (pre-Alzheimer's does that), but I remember a slightly hazy night of looking at the Aurora Borealis when we were sure we could see the shimmering lights of Barrow, Alaska from Prudhoe Bay -- a distance of about 150 miles.
 
Apr 11, 2001
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A question for the optics experts - why do things at sea seem much closer than they really are? When we went on the 96 expedition with RMST, the 2 liners seemed on top of each other but were in reality one mile apart. The rocket re-enactment seemed so close- one would almost think it possible to swim on over to the closer ship and the ship 17 miles out seemed just a short distance away. I understand this is a hazardous phenomenon to swimmers who head out for an island or buoy only to find the distance is far greater.
 

Dave Gittins

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Apr 11, 2001
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I don't think it's optics. It's just that it's very hard to do on sea something that most people can't do on land. How many can estimate if a car is a mile down the highway or a mile and a half?

At sea it's worse because of the lack of reference points and it's even worse if you have no idea of the size of the ship you are watching. You have to use methods like finding how far off your horizon is from the nautical tables and then considering where the ship lies in relation to your horizon. At night it's close to impossible to estimate a light's distance off, especially if you have no idea of its intrinsic brightness.
 
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Dragos Dumitru

Guest
Thank you all for your answers.

To Mr. David Brown and Mr. Michael Standart:
In the light of what you told me I think it becomes even clearer that Captain Smith and his officers are the only ones to blame for not taking the necessary measures dictated by the circumstances, if we keep in mind that other captains did stop their ships during the night and waited for daylight. So, from this narrow, technical point of view, if you like, the captain bears the whole responsibility for the safety of the ship. My father was a mechanical officer on ships navigating on river Danube and he also was implicated in a shipwreck in Austria and probably my point of view is shaped by this accident provoked by the deck officers, especially the pilot.
In terms of why Cpt. Smith did not take any precautions regarding the safety of the TITANIC, considering his experience and his age, I think the problem is much more complex...
If we look at the historical background of that era we'll see that Great Britain was on top of the industrial revolution which, by that time, had reached its climax. And, if I get this right, there was this mood of great confidence in technology and this relish of what science and industry can do. And at the time when TITANIC was built the media exaggerated her qualities, characteristics and all, inducing this feeling that she was unsinkable. Even Cpt Smith noted that modern ships had passed beyond any conditions that would have made them sink, a statement that today seems very naive, although we have much better technologies than ever.
So it seems to me that the sinking of the TITANIC was a turning point not only in maritime history but it had this tremenduos psychological impact of shaking this blind belief that science, technology and industrial revolution can make man omnipotent and can tame the forces of nature.
Of course, all these things are evident for us today, but in 1912 they came as a terrible shock.
 

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