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Why a Traffic Flow Suddenly Turns into a Traffic Jam (2013)

nautil.us

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Re: Why a Traffic Flow Suddenly Turns into a Traffic Jam (2013)

#21

Post by sl1ck731 »

cryptonector wrote: post #11
c22 wrote: post #8

Earlier quoted context omitted.

One of the biggest problems I experience on freeways in the US is that traveling 5 or even 10 mph above the posted speed limit makes you a "slow driver". So even though you might feel that travelling at or above the maximum legal speed limit should give you the right to occupy the "fast" lane someone will prove you wrong by screaming up your ass at 80 mph, 90 mph, or more, flashing their high beams and becoming irate…

You don't get the "right" to "occupy" the left lane just because you're going fast. You have the obligation to yield the passing lane to anyone who wants to go faster. You do not know who has an emergency , and who doesn't. You don't get to enforce one law (speed limits) and flout the other (yield the passing lane). In fact, you don't get to enforce any laws if that isn't your job, and if it were your job, you should…

You don't get the right to speed due to an emergency. Call an ambulance.

To your other point, it is not "flouting the other" law (yield the passing lane) if its 1 person doing 100 mph trying to pass you. The law is in respect to the "normal" flow of traffic, not the fact that any one person is trying to go faster than you.

Re: Why a Traffic Flow Suddenly Turns into a Traffic Jam (2013)

#22

Post by LiamPa »

fosk wrote: post #2

In the US one of the biggest problems I have experienced is that drivers do not adhere to the international rule of having slow drivers on the right side of the freeway, especially in California. As a result to this there are more lane splitting episodes (even within the speed limit) in order to finally being able to keep moving at a faster speed because the lane is effectively blocked by other drivers. In addition t…

In the UK this is illegal, since 2013 police can fine up to £100 and three points on your license however I don’t think it has made a blind bit of difference. Aggressively moving to the slow lane after overtaking sometimes helps..

Re: Why a Traffic Flow Suddenly Turns into a Traffic Jam (2013)

#23

Post by dreamcompiler »

cryptonector wrote: post #11
c22 wrote: post #8

Earlier quoted context omitted.

One of the biggest problems I experience on freeways in the US is that traveling 5 or even 10 mph above the posted speed limit makes you a "slow driver". So even though you might feel that travelling at or above the maximum legal speed limit should give you the right to occupy the "fast" lane someone will prove you wrong by screaming up your ass at 80 mph, 90 mph, or more, flashing their high beams and becoming irate…

You don't get the "right" to "occupy" the left lane just because you're going fast. You have the obligation to yield the passing lane to anyone who wants to go faster. You do not know who has an emergency , and who doesn't. You don't get to enforce one law (speed limits) and flout the other (yield the passing lane). In fact, you don't get to enforce any laws if that isn't your job, and if it were your job, you should…

This. I've had this discussion with many people who think they're entitled to use the left lane if they're going the speed limit or above, because they see themselves as enforcing the speed limit for the people behind them. I ask them to show me their badge, and when they cannot I explain that they have no authority to enforce speed limits without one. Most of them still don't get it.

Re: Why a Traffic Flow Suddenly Turns into a Traffic Jam (2013)

#24

Post by Noumenon72 »

legohead wrote: post #9

I've been intrigued by traffic after moving to SoCal from Oklahoma. day after day you will hit pockets of slowness only to find out there was no obstruction. in the past I read about 'shockwaves' in traffic. one guy changes lanes too fast, which causes multiple lanes to hit their brakes, and then you get the shockwave effect ("Jamiton" in this article) and it lasts a long time. but after doing enough highway driving,…

What I see here in Maryland is that there is plenty of room for every car to merge onto the highway, except that nobody moves left to let them in. Why would you stay in a lane where you can see you're going to be slowed down and even have to brake, when you could move over, maintain your speed, and make room for others? I don't know, but that seems to be the majority's instinct.

Re: Why a Traffic Flow Suddenly Turns into a Traffic Jam (2013)

#25

Post by Rychard »

sl1ck731 wrote: post #21
cryptonector wrote: post #11

Earlier quoted context omitted.

You don't get the "right" to "occupy" the left lane just because you're going fast. You have the obligation to yield the passing lane to anyone who wants to go faster. You do not know who has an emergency , and who doesn't. You don't get to enforce one law (speed limits) and flout the other (yield the passing lane). In fact, you don't get to enforce any laws if that isn't your job, and if it were your job, you should…

You don't get the right to speed due to an emergency. Call an ambulance. To your other point, it is not "flouting the other" law (yield the passing lane) if its 1 person doing 100 mph trying to pass you. The law is in respect to the "normal" flow of traffic, not the fact that any one person is trying to go faster than you.

When my father had a heart attack, I was told to drive to the hospital, which was a ~10 minute drive (at the speed limit). Another family member called the hospital to let them know we were coming.

During this drive, the speed limit mattered very little to me, and I drove as fast as I possibly could.

Whether this was "right" or "wrong" isn't something that crossed my mind at the time. When one's own life (or the life of a loved one) is on the line, people have a tendency to do things that don't make sense to an outside observer.

Luckily for us, we arrived at the hospital without further incident, and my father was quickly cared for. I didn't time the trip, but I imagine it was only marginally faster than driving at the speed limit, as my vehicle at the time wasn't particularly fast.

Re: Why a Traffic Flow Suddenly Turns into a Traffic Jam (2013)

#26

Post by h3mb3 »

c22 wrote: post #8
fosk wrote: post #2

In the US one of the biggest problems I have experienced is that drivers do not adhere to the international rule of having slow drivers on the right side of the freeway, especially in California. As a result to this there are more lane splitting episodes (even within the speed limit) in order to finally being able to keep moving at a faster speed because the lane is effectively blocked by other drivers. In addition t…

One of the biggest problems I experience on freeways in the US is that traveling 5 or even 10 mph above the posted speed limit makes you a "slow driver". So even though you might feel that travelling at or above the maximum legal speed limit should give you the right to occupy the "fast" lane someone will prove you wrong by screaming up your ass at 80 mph, 90 mph, or more, flashing their high beams and becoming irate…

While I think you shouldn't be a self-righteous bottleneck on the left lane, it is clear that speeding is a major factor in these highway traffic jams. It makes it impossible to keep reasonable gaps between cars as drivers always try to go as fast as possible, getting too close to the next car in the process. This always makes me go crazy when driving in the US (although this problem is probably pretty universal to any country with a lot of traffic).

Re: Why a Traffic Flow Suddenly Turns into a Traffic Jam (2013)

#27

Post by scarejunba »

Noumenon72 wrote: post #24
legohead wrote: post #9

I've been intrigued by traffic after moving to SoCal from Oklahoma. day after day you will hit pockets of slowness only to find out there was no obstruction. in the past I read about 'shockwaves' in traffic. one guy changes lanes too fast, which causes multiple lanes to hit their brakes, and then you get the shockwave effect ("Jamiton" in this article) and it lasts a long time. but after doing enough highway driving,…

What I see here in Maryland is that there is plenty of room for every car to merge onto the highway, except that nobody moves left to let them in. Why would you stay in a lane where you can see you're going to be slowed down and even have to brake, when you could move over, maintain your speed, and make room for others? I don't know, but that seems to be the majority's instinct.

Perhaps they are waiting for the next exit. Then they'd be moving out and then coming back in. Going slowly but guaranteeing your slot in to your exit is better than keeping speed and not being able to get back in.

You can't trust the other traffic to give you room. After all, you look like a guy who just decided to overtake one exit before his own.

Re: Why a Traffic Flow Suddenly Turns into a Traffic Jam (2013)

#28

Post by sl1ck731 »

Rychard wrote: post #25
sl1ck731 wrote: post #21

Earlier quoted context omitted.

You don't get the right to speed due to an emergency. Call an ambulance. To your other point, it is not "flouting the other" law (yield the passing lane) if its 1 person doing 100 mph trying to pass you. The law is in respect to the "normal" flow of traffic, not the fact that any one person is trying to go faster than you.

When my father had a heart attack, I was told to drive to the hospital, which was a ~10 minute drive (at the speed limit). Another family member called the hospital to let them know we were coming. During this drive, the speed limit mattered very little to me, and I drove as fast as I possibly could. Whether this was "right" or "wrong" isn't something that crossed my mind at the time. When one's own life (or the life…

I would have done the same thing.

It doesn't mean there is a law granting us permission to do so, which was the part of the comment I replied to that I took issue with.

Its just something that is gray and we have to do when we need to.

It is the same logic as the, "I'd rather be judged by twelve than carried by 6" crowd, interestingly.

Re: Why a Traffic Flow Suddenly Turns into a Traffic Jam (2013)

#29

Post by aarroyoc »

vladvasiliu wrote: post #18
fosk wrote: post #2

In the US one of the biggest problems I have experienced is that drivers do not adhere to the international rule of having slow drivers on the right side of the freeway, especially in California. As a result to this there are more lane splitting episodes (even within the speed limit) in order to finally being able to keep moving at a faster speed because the lane is effectively blocked by other drivers. In addition t…

This is far from universal in Europe. In France, in places where highways have at least three lanes people tend to drive in the middle lane even when traffic is light. Most of the time, outside cities, merge lanes tend to be long enough even for trucks to be able to speed up enough and onramps are relatively far between so I doubt the reason people drive in the middle lane is to avoid incoming traffic. I could see ho…

But it's still forbidden. In Spain it's the same but the rule you learn is "always on the right, except when you're going faster than the cars on the right". And you can't overtake a car when you're on the right, it is only allowed when you're on the left. But there's a lack of enforcement as it is also sometimes difficult to know when someone is breaking that rule.

Re: Why a Traffic Flow Suddenly Turns into a Traffic Jam (2013)

#30

Post by alor »

fosk wrote: post #2

In the US one of the biggest problems I have experienced is that drivers do not adhere to the international rule of having slow drivers on the right side of the freeway, especially in California. As a result to this there are more lane splitting episodes (even within the speed limit) in order to finally being able to keep moving at a faster speed because the lane is effectively blocked by other drivers. In addition t…

As a fellow European with experience driving in California (who prefers driving in the right-most lane), I believe it boils down to a few ways in which CA freeways are different to those in Europe:

  - posted speed limits fairly low (typically 65mph)
  - *much* higher traffic volume
  - traffic consisting of ~95% cars
  - left-lane freeway ramps
  - ramps usually merging directly into the freeway (mentioned by another comment here)
A combination of these factors results in all lanes moving at roughly the same speed (a few mph above the posted limit), which may feel bizarre to a European driver, but certainly improves traffic flow in this specific scenario.

In general, freeways are windy (similar to most European 'dual carriageways'), which requires low speed limits, which reduces throughput. Since the traffic volume is very high, to increase throughput left-lane ramps and ramps merging directly into the freeway are introduced, which may cause occasional hiccups, but on average works well. Since the vast majority of vehicles are cars, all travelling at roughly the same speed, the highest throughput can be achieved by fully occupying all lanes.

There was an interesting related discussion on HN on a few occasions about the best way to utilise escalators at metro stations - see e.g. https://news.ycombinator.com/item?id=10916704

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