"Ask a Traffic Engineer" post in Something Awful forum

[kurumi]

From summer 2009, this "Ask me about being a traffic engineer" post runs to 46 pages and gets quite roadgeeky:

http://forums.somethingawful.com/showthread.php?threadid=3177805&userid=0&perpage=40&pagenumber=1

If you're not a member (I'm not), their profanity filter does some odd things. The phrase "What the gently caress" arises from "gently caress" being substituted for a different verb.

[agentsteel53]

what is caressed in the most gentle of fashions is that you have to register to get to page 2 and higher ...

[J N Winkler]

Of what I showed in the OP, I've only personally done the Hartford freeway model. I'm only 24; my construction experience is limited to working on one freeway in France, some transportation management, and a few dozen repair/rehabilitation projects in the US.

Got quite a bit of growing up to do.

[realjd]

Blocked. Reason: Obscene/Tasteless

Guess I'll have to check it out when I get home!

[Michael]

what is caressed in the most gentle of fashions is that you have to register to get to page 2 and higher ...

I didn't have to.  I'll have to read all 46 pages when I have nothing better to do! 

[Scott5114]

Blocked. Reason: Obscene/Tasteless

I always love internet filters that get to decide for you what you'd find "tasteless"...

[Michael]

I was trying to find the SomethingAwful thread linked in the OP last night, and this thread was one of the results when I was Googled it.  In addition, I found another similar thread on kffl.com called "Ask A Highway Engineer A Question".  I started reading it, and saw a few things I thought I'd mention here.

Reply #21 in the thread used the following picture as an example of construction barrels:


Is it sad that I instantly recognized it as being under the Gowanus Expressway?

Reply #29 sums up PennDOT in a single sentence:

PennDOT is a thread of its own

Also, reply #30 may or may not be from an Alanlander since their title on the forum is The Noble Goat.

As for the SomethingAwful thread, it's currently locked to non-members, but it has randomly let me read it from time to time.

[Alps]

Is it sad that I instantly recognized it as being under the Gowanus Expressway?

*thread marked NEW*
*opens thread*
*hmm, that's the Gowanus, what's that doing here?*
*starts reading your post*

also, i'm 75% certain that's westbound.

[NE2]

I'm 100% certain it's westbound, either in signed direction or rough compass direction.

[Duke87]

The position of the shadows under the vehicles to the right says that the sun is roughly overhead but a bit behind and to the right of the photographer. This means that north is forward and to the left which in turn means that he is facing eastbound (eastbound along that 3rd Ave viaduct segment has a northeasterly bearing).

[Alps]

The position of the shadows under the vehicles to the right says that the sun is roughly overhead but a bit behind and to the right of the photographer. This means that north is forward and to the left which in turn means that he is facing eastbound (eastbound along that 3rd Ave viaduct segment has a northeasterly bearing).

Eh what? Depends when the photo was taken. If taken in summer, the sun's to the north of overhead, in which case I flipped your argument.

[Duke87]

The position of the shadows under the vehicles to the right says that the sun is roughly overhead but a bit behind and to the right of the photographer. This means that north is forward and to the left which in turn means that he is facing eastbound (eastbound along that 3rd Ave viaduct segment has a northeasterly bearing).

Eh what? Depends when the photo was taken. If taken in summer, the sun's to the north of overhead, in which case I flipped your argument.

"Eh what?" back atcha. The sun's maximum position in the sky (which occurs on the summer solstice) is 90 minus your latitude plus 23.5 degrees (tilt of the earth's axis). The sun will never be north of zenith in the sky at any location north of 23.5 degrees N (the Tropic of Cancer). New York City is about 40.5 degrees N so the sun is never more than 73 degrees from the southern horizon here.

This is a basic concept: something facing north will never get direct sunlight in the temperate or polar zones of the northern hemisphere. Hence why moss favors the north side of things. Hence why a room on the north side of a building will tend to require less cooling and more heating than a room on the south side.

A natural shadow in New York City cannot possibly be angled to the south.

Also, the clothes those people are wearing and the foliage on the trees in the background indicate that it is indeed summer, which is consistent with the relatively low midday shadow angle (in winter the shadows would be cast further to the north).

[agentsteel53]

"Eh what?" back atcha. The sun's maximum position in the sky (which occurs on the summer solstice) is 90 minus your latitude plus 23.5 degrees (tilt of the earth's axis). The sun will never be north of zenith in the sky at any location north of 23.5 degrees N (the Tropic of Cancer). New York City is about 40.5 degrees N so the sun is never more than 73 degrees from the southern horizon here.

This is a basic concept: something facing north will never get direct sunlight in the temperate or polar zones of the northern hemisphere. Hence why moss favors the north side of things. Hence why a room on the north side of a building will tend to require less cooling and more heating than a room on the south side.

A natural shadow in New York City cannot possibly be angled to the south.

this is completely correct.

I've driven north into the sun before... in Argentina.

[Alps]

The position of the shadows under the vehicles to the right says that the sun is roughly overhead but a bit behind and to the right of the photographer. This means that north is forward and to the left which in turn means that he is facing eastbound (eastbound along that 3rd Ave viaduct segment has a northeasterly bearing).

Eh what? Depends when the photo was taken. If taken in summer, the sun's to the north of overhead, in which case I flipped your argument.

"Eh what?" back atcha. The sun's maximum position in the sky (which occurs on the summer solstice) is 90 minus your latitude plus 23.5 degrees (tilt of the earth's axis). The sun will never be north of zenith in the sky at any location north of 23.5 degrees N (the Tropic of Cancer). New York City is about 40.5 degrees N so the sun is never more than 73 degrees from the southern horizon here.

This is a basic concept: something facing north will never get direct sunlight in the temperate or polar zones of the northern hemisphere. Hence why moss favors the north side of things. Hence why a room on the north side of a building will tend to require less cooling and more heating than a room on the south side.

A natural shadow in New York City cannot possibly be angled to the south.

Also, the clothes those people are wearing and the foliage on the trees in the background indicate that it is indeed summer, which is consistent with the relatively low midday shadow angle (in winter the shadows would be cast further to the north).

So you're saying when I went to Canada and had the sun rising due northeast and setting due northwest, I was imagining it?

[NE2]

Yes.

[agentsteel53]

So you're saying when I went to Canada and had the sun rising due northeast and setting due northwest, I was imagining it?

that's not "due north".  in the northern hemisphere, the sun is due north at midnight.  in most places, at most times, it is below the horizon.

something facing north will never get direct sunlight in the temperate or polar zones of the northern hemisphere.

this, however, ends up being incorrect in certain situations.  above the arctic circle, during the summer, the sun will be above the horizon at midnight.  that's the only way you will ever get a south-pointing shadow in the northern hemisphere.

[6a]

From summer 2009, this "Ask me about being a traffic engineer" post runs to 46 pages and gets quite roadgeeky:

http://forums.somethingawful.com/showthread.php?threadid=3177805&userid=0&perpage=40&pagenumber=1

If you're not a member (I'm not), their profanity filter does some odd things. The phrase "What the gently caress" arises from "gently caress" being substituted for a different verb.

Huh, I actually have a couple of posts buried in that thread somewhere.  I gave him a before and after aerial of the Spring-Sandusky interchange and the before blew his mind.  He also remarked how Columbus was lucky for a city of its size having two beltways - something I'd always taken for granted but I see his point.

Actually, now that I think about it, I wonder why ODOT has never given the innerbelt a single route number, even if it were in addition to the current 70, 71, 670 & 315.

[Duke87]

So you're saying when I went to Canada and had the sun rising due northeast and setting due northwest, I was imagining it?

that's not "due north".  in the northern hemisphere, the sun is due north at midnight.  in most places, at most times, it is below the horizon.

something facing north will never get direct sunlight in the temperate or polar zones of the northern hemisphere.

this, however, ends up being incorrect in certain situations.  above the arctic circle, during the summer, the sun will be above the horizon at midnight.  that's the only way you will ever get a south-pointing shadow in the northern hemisphere.

OK, fair point: my previous algorithm applies to the position of the sun at solar noon. Approaching dawn and dusk the sun will end up in the northern half of the sky, particularly so at higher latitudes.

The shadows in that picture are clearly midday shadows, though, so my assessment of the direction the picture is facing holds.