Temperature chart for the last 11,000 years - <AUTHOR> http://kottke.org/13/09/temperature-chart-for-the-last-11000-years <comment><USER2> For a little while I was interested in paleoclimatology and I started studying how researchers developed these historical temperature reconstruction curves. Basically you take "proxies" for temperature, things like tree rings, coral growth, sediment layer thickness, etc. and you posit a relationship between the proxy measurements and temperature. Measurements that better fit the hypothesized model get more weight in the temperature reconstruction.

The main problem is that no one knows if the hypothesized models (temperature vs. tree ring thickness, sediment layer thickness, etc.) have any validity. Why should tree rings grow linearly with temperature- what about a huge number of other variables? The temperature "signal" is at best very weak. Decoupling the temperature signal from other variables (humidity, elevation, tree species, CO2 concentration, etc.) is a hugely difficult multivariate statistics problem and most of the researchers I've corresponded with do not seem to appreciate this fact.

Another major problem is that proxies get weighted in the temperature reconstruction based on how well they fit the hypothesized temperature model. The weighting is where things get really shaky. Right away, you have biased your results in such a way that that nonconforming data is discarded / de- weighted. Note that there is not anything wrong with these nonconforming samples that invalidates them; they just don't fit the proposed models very well. Typically researchers develop their own methods for weighting samples in the temperature reconstructions and many of these methods would make a statistician cringe. Often during the weighting phase you find that a handful of proxy samples (out of a sample size of hundreds) get the vast majority of the weight in the temperature reconstructions. Sometimes the weight of a temperature reconstruction in a location is almost completely computed from a few proxy samples taken halfway around the world at a completely different elevation.

If you try to discuss these fundamental problems with climate scientists you'll typically get told that you're not a scientist (not true) or that you're a "denialist" being paid by big oil (not true). I am convinced that these temperature reconstructions are useless at best.

<comment><USER3> It's definitely not the case that climate scientists are uninterested in discussing methodological problems with paleoclimate proxies. A considerable amount of the literature is taken up with doing precisely that, and it takes up a good portion of the Paleoclimatology section of the IPCC report: [http://www.ipcc.ch/pdf/assessment- report/ar4/wg1/ar4-wg1-cha...](http://www.ipcc.ch/pdf/assessment- report/ar4/wg1/ar4-wg1-chapter6.pdf)

<comment><USER2> I know that some folks in paleoclimatology are interested in these core methodology problems. But these concerns are not conveyed to a wider audience. When a temperature reconstruction graph is released to the public there is no mention at all of these problems and one can easily get the impression that these reconstructed temperatures can be known almost as accurately as going outside and taking a reading from a thermometer.

<comment><USER4> Can the public understand that?

Excluding math, we use proxies for just about all science. With different assumptions and different criteria. I don't deny that there are politics, assumptions and margins of error but they do put effort in to minimizing them and doing real science. Take a look at pharmaceuticals, they don't even know why a lot of medicine works, in fact there is debate on if it even does... But people still buy it and take it.

<comment><USER5> The public can't understand that, but it certainly forms opinions based on it. It votes, too...

<comment><USER6> The public is, honestly, incapable of understanding, or even caring, about underlying issues in proxy temperature modeling. A large amount of the public is incapable of distinguishing between weather and climate.

Proxy temperatures, statistical methods, atmospheric modeling, etc, are all scientific areas whose knowledge can be gleamed at sufficiently well for a person with some form of higher education in science or math education (but only barely; remember that this stuff is being researched by people who have devoted their entire lives to the scientific specialty). But that is an astoundingly low proportion of the population. And even then it is clear that, as methodological errors have diminished and methods for more accurate models have appeared, that they all tend towards the same conclusion.

We should be worrying significantly more about the small but non-trivial (and ever-increasing) probability of an extinction event within the next decades rather than pretend that methodological errors, at this point, are a significant issue in identifying the climate trends we have spotted in the last decades.

</comment></comment></comment></comment></comment></comment><comment><USER3> Sources,

The _Science_ paper: [http://www.usu.edu/geo/physical/MarcottEtal_Science_2013.pdf](http://www.usu.edu/geo/physical/MarcottEtal_Science_2013.pdf)

Online supplemental material: [http://www.sciencemag.org/content/suppl/2013/03/07/339.6124....](http://www.sciencemag.org/content/suppl/2013/03/07/339.6124.1198.DC1/Marcott.SM.pdf)

The figure itself is a new plot by Potsdam University researchers for realclimate.org, though, using the same dataset, but not a graphic taken directly from the paper (the paper's Fig. 1 has some alternate versions).

<comment><USER7> I think this stinks. The _Science_ paper says their reconstruction is smoothed and has low time resolution. They say it preserves no variability at all on timescales <300 years, and attenuates even 1,000 year variations. Superimposing this with the 30-year Hadley data seems misleading, because it is on a very short timescale which is suppressed from the paleologic data.

(edit):

 _" Because the relatively low resolution and time uncertainty of our data sets should generally suppress higher-frequency temperature variability, an important question is whether the Holocene stack adequately represents centennial- or millennial scale variability. [...] The results suggest that at longer periods, more variability is preserved, with essentially no variability preserved at periods shorter than 300 years, ~50% preserved at 1000-year periods, and nearly all of the variability preserved for periods longer than 2000 years (figs. S17 and S18)."_

<comment><USER3> The realclimate.org post discusses that as a potential issue, yes. See the section following the sentence: _Because the proxy data have only a coarse time resolution – would they have shown it if there had been a similarly rapid warming earlier in the Holocene?_

<comment><USER7> I read this as "no, it wouldn't show up".

 _" Had there been such a global warming before, it would very likely have registered clearly in some of these data series, even if it didn't show up in the averaged Marcott curve."_

I'm not arguing their conclusions. I'm criticizing _the way they present this data_. This composite reconstruction is so weak, that if you shifted 20th century AGW back 5,000 years, it would completely erase it. That's how powerful the smoothing is.

<comment><USER3> I can buy that view, yeah. It presents conclusions that are probably true, but the plot is a bit in the pop-science direction in doing so, in the sense that the plot itself is not really a rigorous way of establishing those conclusions. The paper doesn't include this kind of plot, probably for those reasons.

</comment></comment></comment></comment></comment><comment><USER8> Throwing my hat into the ring here:

1) I think that we, as the human population, should actively move toward more efficient, less destructive industry on principle, not just because of the threat of climate change. I think making it about climate change gives too many opportunities for argument derailment. Think about when "tree hugger" was a pejorative term; i mean, who DOESN'T want to hug a tree? I think it's a lot harder for people to argue against the idea of "leave a place as you found it" than to find flaws a data set. It also allows for much broader regulation. For example, we could then start focusing on legislation against pharm manufacturers allowing meds to seep into the water supply rather than just the air pollution they're producing.

2) I'm starting to wonder why we're not focusing more on adaptation to than prevention of climate change. I've been watching a lot of TED talks lately (thanks, Netflix!) about the impact of climate change, and the one that I'm thinking of was a researcher who spent time in the arctic studying the wildlife there, and made the case that we should prevent climate change so that we can save arctic wildlife. But I wonder, if we were alive in the age of dinosaurs, would we be saying that we need to clean up the atmosphere to prevent the impact winter that would inevitably kill them? While I love wildlife, I almost feel like it's not our responsibility as humans to tamper with natural processes like extinction. In our prevention efforts, we may also be preventing natural selection and, by extension, adaptation. It could be a reality that we'll face an extinction event that wipes out all other non- domesticated mammalian life. While we can all agree that an Earth like that would suck, we know that, 600 million years from now, EVERYTHING will be wiped out. People speculate that, at this time, humans themselves will either become extinct or will have migrated off the planet. So, my question is, are we prepared to jump ship if Earth becomes uninhabitable? Is it realistic to try to change all 5,000,000,000,000,000,000 kilograms of atmosphere, or should we starting thinking about building habitats for space living?

<comment><USER9> _While I love wildlife, I almost feel like it 's not our responsibility as humans to tamper with natural processes like extinction._

The fundamental premise is not that extinction is bad, but that extinction _we cause_ is bad. If a fox tramples your neighbor's garden, that's too bad. If _you_ trample your neighbor's garden, you should fix it.

<comment><USER8> I used to agree completely with you, but now I realize that, given the second law of thermodynamics, it's impossible to restore an entire ecosystem back to a previous state. From what I hear, one goal of ending climate change is to allow icecaps to re-form and to last longer throughout the year, which ostensibly will end the suffering of polar bears "stranded" at sea. However, even if we _did_ remove all excess amounts of greenhouse gases from the atmosphere (which, as of today, is something that's _barely_ discussed seriously), it's not going to suddenly reverse the adapted behavior of polar bears. This is a totally hypothetical and unscientific story, but let's pretend that the ice caps melted such that polar bears were forced inland and began foraging for food in human-populated areas. In response, the government of Canada single-handedly puts up the money to remove all excess greenhouse gases from the atmosphere. Over a period of decades, the ice grows back, but: do we really expect the polar bear population, which has now adapted to foraging for garbage, to suddenly move _back_ to their initial habitat? Chances are, food will be more plentiful for them in a human-populated area. Now let's assume that polar bears play a significant role in seal population control. Well, now that the polar bears have adapted and are now living further inland, the seal population booms in the arctic region. In fact, it gets so big, that now penguin populations are in rapid decline! So, at this point, we've spent probably trillions of dollars, haven't really _helped_ the polar bears at all, and have directly contributed to the endangerment of penguins. _And this is all assuming that our plan even works!_ Not to mention the fact that there may be other species that died off that played a huge impact on balancing the ice-filled arctic ecosystem.

So, given that scenario, I think the better question to ask is, what benefit would we, as humans, get from a return to a cooler Earth? IMO wildlife will take care of itself: adapt, die off, etc. the same way it always has. BUT, I think that too often the focus is put on sad-looking animals and melted snowcaps, which makes it seem like global warming is just an "environmentalist" issue rather than a serious threat to human life.

<comment><USER10> Oh, come on, are you trying to say that all endangered species will just adapt to live amongst humans if their habitat is destroyed? Your idea about polar bears foraging for human garbage is laughable: These creatures are (1) purely carnivorous, and (2) incapable of living in warm climates. Polar bear population has plummeted as their natural habitat has dwindled. Further, the reason for wanting to save the polar bear is not just to save one species, but that this animal's decline is a bellwether for the decline of the entire arctic ecosystem. We can't say for sure what will happen if the arctic ecosystem disappears.

The ongoing _massive_ extinction event driven by human activity is a real thing. Do you want to live in a world where the only animals alive are ones that humans raise as livestock, or that thrive amongst humans? Nothing but pigs, chickens, pigeons, sparrows, cockroaches, bass and such. Sounds awfully grim to me, but without serious efforts towards preserving wildlife, this is precisely what the future holds.

<comment><USER11> It is purely a question of having the right technology. There is no law that says that you can not engineer a polar bear that is _not_ purely carnivorous, is capable of living in warm climate and very useful to humans in some way. Same goes about every other species.

And it is not that sad. Well designed ecologies can be diverse and beautiful. Even more diverse and beautiful than naturally evolved once.

<comment><USER12> [citation needed]

<comment><USER11> Well, I can't source precisely that phrasing. But imagine an engineered ecology that is: less cruel than a naturally evolved one; as diverse; also includes some 'dinosaur-killer-sized' asteroid impact aversion system that prevents global scale mass extinctions. Wouldn't you find that ecology more beautiful than a naturally evolved one (that we have now)?

<comment><USER13> Given humanity's track record, my imagined idea of an engineered ecology is not so rosy as yours. Who would do it, and what would their motivations be?

</comment></comment></comment></comment></comment></comment></comment></comment><comment><USER14> Temperature chart for the last 425,000 years: [http://ctdonath.blogspot.com/2012/02/global-climate- change-i...](http://ctdonath.blogspot.com/2012/02/global-climate-change-in- context.html?m=1)

<comment><USER15> Do you know why the original 11,000 year chart doesn't look anything like the 10,000 year chart in your link?

<comment><USER16> His chart is based on a single data set (the vostok ice core) for the majority of that period (plus modern temp records slapped on at the end, but it's not visible in the 10,000 year graph) which is not representative of global climate. Correlating proxy records with modern instrument records of temperature is not trivial either (which becomes far more apparent once you look at more than a single proxy record).

It's just cherry picked data to make a cheap political point. The scale of the vertical axis makes it very hard to see what is happening during interglacials, which is what we are in at the moment. If we were worried about an ice age arriving in the next couple of centuries the choice of scale might have some merit, to show how much colder it could possibly get. But we are worried about rapid heating, which that scale does a good job of hiding.

<comment><USER9> Why do people worry about the possibility of entering an ice age? That seems like the sort of thing humanity is much more prepared to survive.

<comment><USER17> We are more prepared to survive a 10 degrees drop than a degree and a half increase?

<comment><USER9> Not so much that a degree warmer is hard to survive, but the associated things that either come along with or are implied by global warming seem more damaging than colder weather and more ice, which we already know humans survived no problem ages ago when they migrated through Siberia and Alaska.

</comment></comment></comment></comment></comment></comment><comment><USER18> My skepticism in climate change is based on a long history of censuses in the scientific community that later proved to be completely wrong.

I'm not saying we should not try to understand the world. I'm saying we should realize we have limits. The more complex the system we seek to understand, the more we should be skeptical. The climate of the entire planet and to the degree one particular species impacts it seems extremely complex to me. Hence, I am highly skeptical.

<comment><USER19> No one is saying that we should devote 100% of GDP to mitigating global warming. Go ahead, factor in the uncertainty. What % of GDP should we spend to avert the very real possibility catastrophic warning occurs? What % are we spending?

<comment><USER18> If it were left up to me, I would say we should have zero forced spending and an unlimited amount of voluntary spending to avert a potential global warming catastrophe.

Let me remind you, that at any time you are free to donate any amount of your own money to thwart global warming. That's not what some people really want though. They don't want to spend their own money on the problem. They want to spend other people's money on the problem. And I contend we don't know nearly enough about the issue to cross that line.

<comment><USER20> Really what you are saying is do nothing, at least be honest about it.

<comment><USER18> Only if you and all the other folks who are convinced of a need to act on global warming choose to do nothing. The reality is that even among those who think "we" need to act, most do not even have enough conviction on the matter to volunteer to spend a dime of their own money on it.

<comment><USER19> Because the world's climate is a public good, game theory predicts that this kind of thing won't ever work.

We are semi-rational actors in a dynamic competitive system. We can all want X to happen, and be willing to spend money to make X happen, but realize that doing so would make our own lives worse because of the non-participation of others, and so we contribute to making X happen not directly, but instead by trying to put rules in place that enforce participation.

I refer you to: [http://en.wikipedia.org/wiki/Public_good](http://en.wikipedia.org/wiki/Public_good) [http://en.wikipedia.org/wiki/Tragedy_of_the_commons](http://en.wikipedia.org/wiki/Tragedy_of_the_commons) [http://en.wikipedia.org/wiki/Game_theory](http://en.wikipedia.org/wiki/Game_theory)

</comment></comment></comment></comment></comment></comment><comment><USER21> Out of idle curiosity, can anyone tell me more about what a 0.4 (0.6, 1, 2...) °C anomaly _feels_ like, maybe with reference to cities that have climates with differing annual averages? I mean, is it like shifting every city 5 ° in latitude closer to the equator, or what?

(I know this wouldn't capture the whole story, I'm just curious.)

EDIT: I guess the state of New York has a range of annual average temperatures from 4 °C to 12 °C, so maybe this isn't useful at all. [http://en.wikipedia.org/wiki/Climate_of_New_York#Temperature...](http://en.wikipedia.org/wiki/Climate_of_New_York#Temperatures)

<comment><USER22> Think of it more as extra energy being imparted to the global weather system. This will have all sorts of fun and exciting effects, and as I understand the warming will be greatest at the poles. Alaska has warmed by about 1.6[0] in the last 60 years, and the interior of Alaska by 1.4° C in the last 100[1], compared to a global temperature rise of .8° C over the same period. This has resulted in the melting of thousands of cubic kilometers of glacial ice, with this study[2] suggesting that this is the largest glaciological factor in rising sea levels.

To the eyes of the native inhabitant, the glacial retreat is shocking, with the lower altitude glaciers most affected. We've built glacier overlooks in some places, where once the glacier was a stone's throw away, and now it's barely visible, and in another few decades the only thing they'll be able to show anyone there are photos. I've seen photos from the early 1900s of glacial termini which towered over the masts of a sail-rigged steamer. Today there is a fjord there, and the glacier is more than 13km away.

And you want to know what that feels like?

How about instead you imagine how it feels to watch the Arctic melting around you, while an endless circus of millions deny that it's even happening.

[0] [http://climate.gi.alaska.edu/ClimTrends/Change/TempChange.ht...](http://climate.gi.alaska.edu/ClimTrends/Change/TempChange.html) [1] [http://oldclimate.gi.alaska.edu/papers/Arctic62-3-295.pdf](http://oldclimate.gi.alaska.edu/papers/Arctic62-3-295.pdf) [2] [http://glaciers.gi.alaska.edu/material/arendt_phd.pdf](http://glaciers.gi.alaska.edu/material/arendt_phd.pdf)

<comment><USER21> > And you want to know what that feels like? How about instead you imagine how > it feels to watch the Arctic melting around you,

I said in the original comment that I was well aware this wasn't the entire story.

There are some subjects where I really wish I could ask questions like someone new to the topic and not immediately be branded as some kind of enemy.

<comment><USER22> My apologies if you read any offense in my words; none was intended. Unless you happen to have a heat ray and a hatred for H20 solids, I can't imagine that you've had much of a personal hand in making it melty up here. I hope the data I provided may serve you even if my rhetoric don't.

<comment><USER21> Ah, sorry for reading too much into your comment.

While I've got you here, and while we're pushing the civil boundaries on the topic, there's something on this subject I'm curious about, but have always been afraid to ask...

Won't a more accessible / inhabitable taiga be kind of awesome?

I mean, low lying areas without hurricane protection swallowed by the seas, algal blooms, the shutdown of the thermohaline cycle leading to a frozen Europe, midwestern desertification, all these are well down the bad side of the ledger. Harms are still outweighing the good. But isn't some of what's going on up north good for humanity?

<comment><USER22> I complain about glaciers, but they're really just the tip of the icefield. Most of the ground here is some variety of permanently frozen (permafrost)[0], so that's all going to melt at some point. Most of the population here does not live on/near permafrost, despite that map. However, if you do happen to go to Fairbanks or some more northerly hellhole, you'll find all the buildings are built on stilts, elevated a few feet off the ground. If they were not, the ground underneath would melt and sink (ice is less dense, remember), and eventually you'd be making a nice cross-stitch for "Home Sweet Bog".

So there's that. There's no soil in most of Alaska; it's either been scraped away by glaciers or the frozen layer is too close to the surface for much to develop. In some places the pine taproots can only get a meter or so down, and you'll have endless forests of man-high spindly pines. In many other places there are no trees at all. This is generally what we call taiga. When the permafrost underneath this melts, you're not going to have fertile soil left behind, at least not for a really long time.

On the plus side, Alaskans are probably not going to complain a whole lot about a warming trend, and the Northwest Passage is finally a thing. Maybe my friend will finally be able to grow avocados? It's hard to come up with a lot of other things that might be beneficial -- maybe we'll have more opportunities for strip mining now that the glaciers are gone. Maybe in a few million years the Alaskan Bog will be a good source of petrochemicals.

Really it's pretty hard to come up with good things, especially compared to "most of the ground will melt". Siberia is likely to be much the same story, as well as large parts of Canada -- you can find your own permafrost maps for there. Oh, and we have problems with coastal storms here too, and are already having to relocate whole villages (Newtok, Shishmaref, etc)[1][2]. Probably the only really good thing is that not a lot of people live here now, otherwise it'd be pretty easy to call the Arctic as the region most severely affected by AGW.

[0] [http://i1109.photobucket.com/albums/h427/m4135/ps9_zps5c9b1b...](http://i1109.photobucket.com/albums/h427/m4135/ps9_zps5c9b1bf0.jpg) [1] [http://en.wikipedia.org/wiki/Shishmaref,_Alaska](http://en.wikipedia.org/wiki/Shishmaref,_Alaska) [2] [http://www.theguardian.com/environment/2013/aug/05/alaska- ne...](http://www.theguardian.com/environment/2013/aug/05/alaska-newtok- climate-change)

<comment><USER21> Ah, thanks! I do appreciate the insight here...

</comment></comment></comment></comment></comment></comment></comment><comment><USER23> googling "industrial revolution averted iceage" returns a few conservative blogs, smugly pleased with the possibility

the only credible commentary i can find is in a nytimes article:

"Scientists say that if natural factors were still governing the climate, the Northern Hemisphere would probably be destined to freeze over again in several thousand years. 'We were on this downward slope, presumably going back toward another ice age,' Dr. Marcott said."

[http://www.nytimes.com/2013/03/08/science/earth/global- tempe...](http://www.nytimes.com/2013/03/08/science/earth/global-temperatures- highest-in-4000-years-study-says.html)

<comment><USER24> I cannot cite the exact words, but in discussions professors have indeed expressed the opinion that a next ice age won't be of concern for us.

Those charts, especially those going back further, are a good argument for why we will need to control the climate at some point in the future (but please not when we have not figured out how to without significant risk).

</comment></comment><comment><USER25> This plot compares an inferred model to the instrumental record. Here is the study expressed in the words of Real Climate: [http://www.realclimate.org/index.php/archives/2013/09/paleoc...](http://www.realclimate.org/index.php/archives/2013/09/paleoclimate- the-end-of-the-holocene/)

      Over the last decades, numerous researchers have
      painstakingly collected, analyzed, dated, and calibrated
      many data series that allow us to reconstruct climate
      before the age of direct measurements. Such data come e.g.
      from sediment drilling in the deep sea, from corals, ice
      cores and other sources. Shaun Marcott and colleagues for
      the first time assembled 73 such data sets from around the
      world into a global temperature reconstruction for the
      Holocene, published in Science. Or strictly speaking, many
      such reconstructions: they have tried about twenty
      different averaging methods and also carried out 1,000
      Monte Carlo simulations with random errors added to the
      dating of the individual data series to demonstrate the
      robustness of their results.

Marcott et al.'s graphic states that their model reflects historical temperatures so accurately that it can measure the average temperature of the entire globe continuously back to 8000 years ago, to within a small fraction of 1 degree Celsius (i.e. the 1-sigma error bars). That is simply an extraordinary claim given:

1) The "divergence problem". The lack of correlation between model inputs like tree rings and the instrumental record over the last few decades is acknowledged by all; climate scientists generally state that it is due to anthropogenic factors, arguably assuming the consequent.

[http://www.skepticalscience.com/Tree-ring-proxies- divergence...](http://www.skepticalscience.com/Tree-ring-proxies-divergence- problem.htm)

2) Serious climate model prediction failures over the past 10 year period, as acknowledged in Nature:

[http://www.nature.com/news/climate-change-the-forecast- for-2...](http://www.nature.com/news/climate-change-the-forecast-for-2018-is- cloudy-with-record-heat-1.13344)

In other words, key model inputs used in climate reconstructions do not strongly correlate with the instrumental record over the last 30-40 years ("the divergence problem") and climate models have so far had a poor track record over the last 15 years, with average temperatures winding up below the envelope of model predictions. These predictive failures in the datasets we can check bode ill for the prospect of hindcasting global average temperatures to within 1 degree more than 8000 years ago.

<comment><USER26> In the same article, they explicitly mention that the study is not based on tree ring proxies. In fact, all the global reconstructions are based on many different proxies.

I also think you misrepresent the 2nd article. The question is what and on what time scale are you trying to predict. I believe they are talking about more precision more short-term models. Just like we can predict winter and not predict weather, we can predict warming due to human forcing, but not the specific details.

In the end, however, it's completely irrelevant to AGW if there was a higher temperature in the past or not. The theory of AGW doesn't stand just on that argument (nor any other single argument, for that matter).

<comment><USER27> Without trying to say too much, one big reason we can predict winter is that we've had hundreds of thousands of years of experience with it.

</comment></comment></comment><comment><USER28> Am I alone in finding the graph scary? This rate of change in temperature is probably not something that would be easy to slow down, yet it feels like not many people care about this.

</comment><comment><USER29> World population chart for the same timeframe: [http://upload.wikimedia.org/wikipedia/commons/b/b7/Populatio...](http://upload.wikimedia.org/wikipedia/commons/b/b7/Population_curve.svg)

</comment><comment><USER30> It seems that the uncertainty is much higher at the end of the blue curve. I wonder why.

It also seems that the red curve has no uncertainty data.

I would not dare draw any conclusion from these curves before I have satisfying explanations for these two questions.

<comment><USER31> It's probably because all the climate scientists in the world are trying to trick you.

</comment></comment><comment><USER32> "Worry about global warming impacts in the next 100 years, not an ice age in over 10,000 years. "

[http://www.skepticalscience.com/heading-into-new-little- ice-...](http://www.skepticalscience.com/heading-into-new-little-ice-age.htm)

Basically none of these memes are new. They often rely on misunderstanding of context. (For those who didn't know, skeptical science rebuts these commonly found arguments against global warming.)

</comment><comment><USER33> Of note is that the chart's error bars fill the entire scale near the end, so the measurements could really be anywhere there. It's anyone's guess whether or not temperatures have somehow mysteriously skyrocketed or not.

My personal inkling is that the alarmist reports are wrong, and the changes aren't as drastic as reported; since the same people publish results from proprietary, rigged climate models.

</comment><comment><USER34> Can someone please explain how we're able to know the temperature in 4,000 BC with an accuracy of +/\- .2° C?

</comment><comment><USER35> Global temperatures are basically flat for the last 17 years, and below every single computer model of climate change. This is even more stark given the fact that the most co2 has been produced in the last 17 years. I think the theory is pretty much broken and they need to figure a better model.

[http://www.dailymail.co.uk/news/article-2420783/Worlds- clima...](http://www.dailymail.co.uk/news/article-2420783/Worlds-climate- scientists-confess-Global-warming-just-QUARTER-thought--computers-got-effects- greenhouse-gases-wrong.html)

<comment><USER36> [http://www.skepticalscience.com/global-warming-stopped- in-19...](http://www.skepticalscience.com/global-warming-stopped- in-1998-intermediate.htm)

The Daily Mail? Really?

<comment><USER35> That's comparing apples to oranges. All the other data used to create the original graph o calculate temperature such as tree rings, etc do not take into account the temperature of the oceans, etc. There may be perfectly good explanations as to why the temperature may be flat, but those same explanations are not being fed into the graph that the OP posted.

<comment><USER16> >All the other data used to create the original graph o calculate temperature such as tree rings, etc do not take into account the temperature of the oceans, etc

[https://en.wikipedia.org/wiki/Proxy_(climate)#Corals](https://en.wikipedia.org/wiki/Proxy_\(climate\)#Corals)

</comment></comment></comment></comment><comment><USER37> How much do we humans contribute to the heating of the world? The heat we output from our bodies and population increases must mean more heat.

I say this because a friend has a small barn and in it two horses, two pigs and some chickens. He said the barn doesn't use any heat source because the heat from the two horses is enough to warm the barn. Even a bucket of water in the barn won't freeze.

<comment><USER13> A human uses about 100W. I don't know about horses, but depending on how well- insulated the barn is, a few hundred watts would make a significant difference.

About those humans heating the Earth -- the effect of the GHG's we emit is tapping into solar insolation, which is huge, so it probably dwarfs the above figures (see next paragraph). Also, the energy that powers us (food) would be turned into heat by other processes anyway.

Order of magnitude: population of 7 billion * 100W/person = 9.7TW. Solar insolation 1361 W/m^2, over the projected area of the earth, which totals 175,000,000 TW.

I just throw that figure (100W) as a useful order of magnitude estimate.

</comment></comment><comment><USER38> The cyclical recurrence of interglacial and glacial periods (we're technically still in one of these) can theoretically be explained by cyclically evolving properties of the Earth's orbit around the sun such as the precession of the Earth's ratational axis (google Milankovitch cycles). This theory is consistent with the gradual cooling trend observed thus far into the Holocene epoch, and predicts it will continue for tens of thousands of years. The linked graph shows this very nicely.

A sudden, full-blown glacial period would be far more disastrous for human civilization than significant global warming. The latter would submerge densely populated coastal areas and force humans to move to the new coastlines, but the overall capacity of the Earth to support life would increase, just as it did at the start of the Holocene. The former would result in a large reduction in the Earth's carrying capacity and global famine.

Any change in the Earth's temperature is going to be disruptive to both human civilization and the existence of other species on Earth. We have reversed the effects of several thousand years of cooling in just a couple of centuries and, assuming we are able to continue extracting and burning hydrocarbons at an unabated pace indefinitely (dubious) we could significantly change the face of the world, but it will still support our civilization, just in a very changed state. Avoiding the pain of this change is ample incentive to curb the use of hydrocarbons. (Edit: It has taken centuries and a significant portion of the world's hydrocarbon reserves to produce less than a degree of warming. At this rate, even if we evaded peak-oil for another thousand years the Earth will still be in a glacial period.)

However, we should be much more aware of events that could trigger another glacial period. Megaeruptions or large meteor impacts could plunge global temperatures suddenly and catastrophically. These are far greater threats to our species, but we are both incapable of adequately predicting them or preventing them if we do predict them. The probability of this sort of event happening in a single human lifespan is remote, while global warming is a certainty, but these events will eventually occur with certainty. Managing global warming is certainly a good idea for the comfort of our civilization, but we should have more eyes on the bigger threats. (Edit: Even if we tried, we would be unable to maintain global warming indefinitely simply by burning hydrocarbons. In the ten-thousand year time-frame we will need to find other ways to combat gradual cooling.)

<comment><USER39> > Managing global warming is certainly a good idea for the comfort of our > civilization, but we should have more eyes on the bigger threats

Orrrr we could do more than one thing at once?

In any case, a "sudden, full-blown glacial period" has never happened according to any geological record we have. The most "sudden" have happened over centuries. The actual, demonstrated suddenness of current warming trends is a major part of the problem.

There are a bunch of problems in your post (I have no idea where you get the idea that we're in a glacial period, these are just labels, but no one calls the Holocene anything but an interglacial; it is well established that Milankovitch cycles do not explain current trends; current atmospheric carbon will be there for centuries to come and will not stop warming us even if we were to stop all emissions today; you neglect ocean acidification, sea level rise, etc), but the fact remains that its ridiculous to assert that "we should have our eyes" on one threat instead of another, when we could have much more scientists and funding for asteroid detection if someone would exert some political will. _That_ is what's necessary, not trying to minimize other threats with specious (at best) arguments.

</comment></comment><comment><USER40> I don't think this chart comes close to proving that Obama was born in the United States.

</comment><comment><USER41> Sorry but I hear a lot of speculation, not real reports of hard actual life threatening changes.

Maybe soft ones like the sea temperature and acidity, but most people can still go out and food still grows.

</comment><comment><USER42> Until you were there to measure the temperature, all you have is just the output of a model. The model is not the world.

</comment><comment><USER43> Start burning tires folks. We need to save ourselves from an ice age.

</comment><comment><USER44> Well, the upside is, we fixed the ice age that was trying to happen.</comment>


The mystique of Goldman Sachs - <AUTHOR> https://www.washingtonpost.com/lifestyle/style/the-eternal-mystique-of-goldman-sachs/2016/12/14/4fa8d4ca-c0ab-11e6-afd9-f038f753dc29_story.html <comment><USER2> One thing HN might care about: 3 years ago, 25% of Goldman employees worked in the IT division. They probably had more developers than Facebook and LinkedIn combined.

[http://www.businessinsider.com/goldman-sachs-has-more- engine...](http://www.businessinsider.com/goldman-sachs-has-more-engineers- than-facebook-2015-4)

<comment><USER3> It's disgusting to me that that much brainpower was/is dedicated to stock trading. All that programming and the only thing we get for it is that we can correctly value a company.

<comment><USER4> Its insane that you think this is the case.

The markets are an incredibly important part of the economy and this technology does not only simply value a company.

<comment><USER5> I thought it was satire. Although you might make an argument for why reducing time-to-trade from 50ms to 100ms would not be the end of the world

<comment><USER6> That would make markets less efficient and thus allocate capital in a worse manner.

<comment><USER7> Less efficient for literally 50 ms. Then it all balances out.

<comment><USER8> The world GDP is about $76 trillion; that means that the global economy produces about $120,000/ in 50 ms. Reducing the time to work on a trade from 100 to 50 ms gives a trading algorithm that much of an edge, which ultimately helps increase the size of that $76 trillion pie.

</comment></comment></comment></comment></comment></comment></comment><comment><USER9> I've been thinking about applying to their IT / analytics teams in the SLC office. Curious if anyone has any anecdotes about the environment. I've worked in financial institutions before, but curious how it compares to the FANGs. I've met really smart people in both environments.

</comment><comment><USER10> Obligatory: [http://www.rollingstone.com/politics/news/the-great- american...](http://www.rollingstone.com/politics/news/the-great-american- bubble-machine-20100405)

"The first thing you need to know about Goldman Sachs is that it's everywhere. The world's most powerful investment bank is a great vampire squid wrapped around the face of humanity, relentlessly jamming its blood funnel into anything that smells like money. In fact, the history of the recent financial crisis, which doubles as a history of the rapid decline and fall of the suddenly swindled dry American empire, reads like a Who's Who of Goldman Sachs graduates."

</comment><comment><USER11> I've been out with my fair share of brokers and salespeople, and Goldman's guys always stick out.

They're always incredibly nosey about what your firm is up to, what your opinion on the market is, what you're thinking in general.

All other brokers are happy to just eat an expensive meal and be pals.

GS guys act like they've all been personally told to get some useful information from the client.

I've noticed the difference when a guy moves away from GS, they stop being so focused on getting info.

</comment><comment><USER12> Macquarie is more interesting IMO. Was only founded in the 60s in an isolated place.

</comment><comment><USER13> >Cut to 2008, when Goldman made money off the economic collapse by shorting the housing market. The firm was charged with fraud in 2010.

First of all, that's non-sequitur. Second, why is it evil to short the housing market?

Washington Post really knows how to cater to its readership...

<comment><USER14> > _Second, why is it evil to short the housing market?_

People don't understand the basic concept that in order to _buy_ something, someone needs to _sell_ something...which is going short.

<comment><USER15> No. It's only going short when you sell something _that you don 't have_ \- that is, you sell something borrowed. It's not clear to me how one would do that with houses. You could short homebuilders and mortgage companies, but that's about all.

<comment><USER16> Mortgage payments are bundled into securities called RMBS. By shorting these securities, you are not shorting the mortgage company, but the assets themselves (the mortgage receivables).

<comment><USER15> _Can_ you short those?

<comment><USER16> Yup, best way to think about them are as bonds in which the credit rating is determined by the underlying asset quality rather than the company itself.

<comment><USER15> TIL.

</comment></comment></comment></comment></comment></comment></comment><comment><USER17> _> To keep reading, please enter your email address._

Thanks, but no thanks.

<comment><USER18> I agree. It's annoying how often HN links to paywalls. Luckily, they aren't hard to get around, more of an announce than anything. Just clear your cookies for the site and try again.

<comment><USER19> Paywalls with workarounds are allowed here. We all agree that it's annoying, but doing without NYT, Economics, New Yorker, WSJ, and (et tu now?) WaPo articles would make be worse.

This is in the FAQ: [https://news.ycombinator.com/newsfaq.html](https://news.ycombinator.com/newsfaq.html) and (suitably, for a FAQ) has been discussed countless times, e.g. [https://news.ycombinator.com/item?id=10178989](https://news.ycombinator.com/item?id=10178989).</comment></comment></comment>


The Racist Talent Show Judge Who Makes Simon Cowell Look Good - mck- http://www.huffingtonpost.ca/suzanne-ma/hollands-got-talent-racist_b_4324894.html

<comment><AUTHOR> I'm a Caucasian born and raised in The Netherlands living in Australia and married to a Thai wife.

Maybe it is because I'm white but I don't really understand the racism here. The type of abuse pointed out in the article isn't really different than picking of fat people, or bald people or people who are to skinny, to tall or to short etc.

To me, personally, racism is about hate. Making jokes or teasing someone about their physical appearance or racial background, to me, isn't racism per se.

My wife told me a story; She worked in a noodle bar behind the counter. One day some people who had eaten in the place paid and when they walked out the door one of them turned around and said to her "Fucking monkey!". Now, to me, that IS racism. Not this because this asshole happen to say this to my wife but because there is a tone of hatred in it.

To me the article sounds a bit juvenile. As if the author thinks that only Chinese or people of Chinese heritage get picked on or teased in daily live. People will pick on each other and will make jokes about each other and they will use the most prominent physical feature to do so.

However, I do agree, this sort of behavior by an adult man (gay) on prime time television is pretty childish.</comment>


CERN to announce Higgs boson observation at LHC - <AUTHOR> http://www.extremetech.com/extreme/108599-cern-to-announce-higgs-boson-observation-at-lhc

<comment><USER2> There are several things to keep in mind when reading things like this piece:

1) Nobody with any actual knowledge about the analysis spoke with anyone who then blogged about it. These people know better. What actually happened was that people in CMS and ATLAS, who don't work on the Higgs analysis, saw the Higgs plots during internal discussions and then told their theorist, blogger friends roughly what they saw.

2) The most familiar exclusion plots are showing the line at which the cross section is excluded at 95% along with the 2-sigma uncertainty on the _expected_ location of this curve. Since the people spreading rumors are not very familiar with the analysis, they do not realize that n-sigma deviations between the observed and expected lines are not the same thing as n-sigma observations. The actual significance of observation will usually be lower.

3) Again because the people spreading rumors are not familiar with the analysis, they are not able to add appropriate caveats about systematic uncertainties, which can substantially reduce significance. Because these rumors started last week, I guarantee the plots on which they were based do not include all systematic effects. And because the bloggers are predominantly theorists, they don't have the experience to add that information themselves either.

So I hope you will take rumors for what they are: rumors.

<comment><USER3> _1) Nobody with any actual knowledge about the analysis spoke with anyone who then blogged about it. These people know better. What actually happened was that people in CMS and ATLAS, who don't work on the Higgs analysis, saw the Higgs plots during internal discussions and then told their theorist, blogger friends roughly what they saw._

Are you saying that you _do_ have actual knowledge, or are you just guessing this stuff just like the others? I'm not trtying to be snarky, I really want to know if you have good hard info or not.

<comment><USER2> Let's just say that regardless of whether I have any actual knowledge about this specific situation, I know that what I outlined is what happens from other, similar situations where I definitely have actual knowledge. Let's also say that if I did have any actual knowledge, I would know better than to confirm it and I would definitely know better than to say what I know to a blogger.

I do know that knowledgeable people will probably be more open-mouthed around this time tomorrow.

<comment><USER4> Ahh the good ole' pre-publication information embargo :)

You're right though... somebody (i.e. one of the thousands of collaborators, from undergrads to PIs) probably got the email that said something to the effect "we'll be releasing results on the search for the Higgs tomorrow, and until those results are released you aren't allowed to talk/tweet/email/post/facebook any information about the experiment. Of course, this doesn't mean they know anything about the paper, only that they know there's going to be a paper that discusses something. The people who really know are going to be the ones with the tightest lips.

</comment></comment></comment></comment><comment><USER5> When the LHC was built - one of the biggest reasons used to justify its massive cost was that it would lead to new physics. Th Higgs sighting is sort of the Good News/Bad News scenario.

At the energies predicted, it falls in nicely with mostly established physics (Standard model). So yes that is the good news part.

The seriously bad news part is that it does not lead us in any new directions at all. Theoretical Physicists usually feed off of Observations from experiments like the LHC and new strange results to expand their frontiers.

For a while now unfortunately they have been going down the Warren of String theory without any falsifiable predictions emerging. Instead people have more or less stumbled in the Anthropic principle as the new be-all and end-all. I was really hoping that there was no Higgs to be found at all OR Super symmetry to be found OR Fine structure constant Variations OR some clue abut dark matter :(

<comment><USER6> I'm not familiar with the topic, but isn't there still room for new discoveries?

<comment><USER5> Yes certainly there is much room to find new and exciting stuff - but "not" finding the Higgs was the lowest hanging fruit. If the LHC were not able to find the Higgs at any energy level, the Standard model wold be rendered incomplete and a lot of "new" new Physics would follow. They would have had to explian how Mass is introduced into the model without relying on the Higgs Field.

Now (if this is confirmed to the 5 sigma needed) the experimenters have to actually go looking for new stuff - a harder proposition, fraught with interpretations and Agendas.

<comment><USER7> New for the sake of "new" doesn't make much sense to me. Quoting Einstein "It can scarcely be denied that the supreme goal of all theory is to make the irreducible basic elements as simple and as few as possible without having to surrender the adequate representation of a single datum of experience." If indeed Higgs boson is spotted, it will be indeed a exemplary triumph of this thought, since the core premise of standard model is symmetry and simplicity.

I consider LHC as the best microscope we humans ever build. Our exploratory quest and adventure will remain ever more interesting and baffling when we start to probe in higher energy levels. This will be irrespective of whether the presence of Higgs boson is established or not. And there is no reason to think otherwise, since in the past the deeper and in finer scales we probed, strange phenomena had popped out, requiring more new theorems and scientific understanding to explain them.

</comment></comment></comment></comment><comment><USER8> I may be in the minority, but I'll be slightly disappointed (although extremely impressed) if CERN actually does announce they've sighted the Higgs.

I'll be slightly disappointed because there's something appealing in the possibility that the universe doesn't fit nicely into an equation.

On the other hand, that our great minds were able to see a problem, come up with a solution, test it and then say "Yes, we accurately predicted an unobservable, and yet fundamental principal of our universe" would be damn impressive.

<comment><USER9> > I'll be slightly disappointed because there's something appealing in the > possibility that the universe doesn't fit nicely into an equation.

iirc, the Standard Model is a few pages of equations. Not nicely at all.

<comment><USER10> "A few pages of equations" is pretty damn good for _the software the universe runs on_. Imagine saying "iirc, Portal's physics engine is a few pages of code. Not concise at all".

(In fairness, we can be fairly sure that the Standard Model isn't the whole deal; it doesn't do gravity properly, for instance. And you need more than just the bare equations to explain what's going on -- though I think a lot of that is just impedance matching for the benefit of our not-very-mathematics- tolerant brains. But, still. "A few pages" isn't so bad.)

<comment><USER11> A couple of issues with your comparison: math is _much_ more succinct than most code--it's more like a few pages of APL than a few pages of C++; also, code has to deal with performance so elegant solutions tend to give way to complicated messes in the face of finite hardware and imperfect optimizing compilers.

That said, you do have a good point. However, extreme complexity arising from a simple input is not _that_ surprising--just look to the r pentomino in the game of life or the Mandelbrot set.

</comment></comment></comment></comment><comment><USER12> CERN apparently said the following in a press release, which puts some substantial limits on what's actually going to be announced:

"A seminar will be held at CERN on 13 December at which the ATLAS and CMS experiments will present the status of their searches for the Standard Model Higgs boson. These results will be based on the analysis of considerably more data than those presented at the summer conferences, sufficient to make significant progress in the search for the Higgs boson, but not enough to make any conclusive statement on the existence or non-existence of the Higgs."

I got that from Matt Strassler's blog entry below (which is worth reading):

[http://profmattstrassler.com/2011/12/07/about-those- rumors-t...](http://profmattstrassler.com/2011/12/07/about-those-rumors-that- the-higgs-has-been-discovered/)

</comment><comment><USER13> Here's the link to the seminar. It is titled "Update on the Standard Model Higgs searches in ATLAS and CMS". There, you can find a link to the webcast, since it will be broadcasted live at 14h CET tomorrow, Dec 13: <http://indico.cern.ch/conferenceDisplay.py?confId=164890>.

From CERN's general director: "ATLAS and CMS experiments will present the status of their searches for the Standard Model Higgs boson [...] based on the analysis of considerably more data than those presented at the Summer conferences, sufficient to make significant progress in the search for the Higgs boson, but not enough to make any conclusive statement on the existence or non-existence of the Higgs."

</comment><comment><USER14> Is there a way to explain the Higgs mechanism to a lay computer scientist?

<comment><AUTHOR> Yeah -- I've seen it described like this before:

Basically, Higgs boson particles are like paparazzi (or fans) around a celebrity (the observable matter that we already know about).

The Higgs boson particles, by affixing onto the celebrity, make their movement slower/harder -- i.e. they give the celebrity mass/substance.

That's the theory, anyway :)

<comment><USER15> So there's a "Higgs field" that all objects move through and those objects which have inertial mass are affected by this field? And inertial mass is the result of interchanges of the force carriers (higgs particle) between objects with inertial mass?

Inertial mass is ubiquitous. Why does it take so much power to make the Higgs boson detectable? How _do_ you detect it?

Is the Higgs boson one of the hypotheses of Newton's famous phrase "Hypotheses non fingo."?

<comment><USER16> To make the Higgs detectable means making a sufficiently high concentration of energy to make a Higgs particle. That concentration of energy is dependent on the mass of the particle (and hence energy by e=mc^2). The Higgs boson is theorized to exist at relatively high mass, hence making it difficult to create. This higgs particle will decay into a shower of other particles and these particles will decay, and all these remnant are detected and analyzed to recreate the original event. So no, Higgs is quite well understood and we expect to find it for strong reasons.

<comment><USER15> But mass is everywhere, so aren't there Higgs bosons everywhere too?

If so, what is the difference between detecting the Higgs boson via the presence of mass (i.e., "These particles have mass so there must be one or more Higgs boson nearby) versus detecting the Higgs boson as a separate particle?

<comment><USER16> The excitation of the higgs field corresponding to higgs boson's like we are looking for at LHC are 'manifested' so to speak. The higgs that cause mass are virtual carrier particles that exist in a state of quantum in betweenness. Photons, for example are the carriers of the electromagnetic force. They are not the same, however, as the photons transmitted to your eye. So you don't see photons being traded between magnets when you hold them together, but can see the photons bouncing off the magnets from the sun. In the same way we can't see the higgs carrier particles, but can see (hopefully) the higgs bosons at LHC.

</comment></comment></comment></comment></comment></comment><comment><USER17> Aside from the good explanations of what the Higgs is below, can someone explain why discovering the Higgs would be significant? I.e. what problems does it help illuminate.

</comment><comment><USER18> Oh my god, this is amazing. Congratulations!

</comment><comment><USER15> Is this important to string theory?

</comment><comment><USER19> Ugh, the mobile version of that site is awful to use on an iPad.</comment>


Google Fiber: 20% of Neighborhoods Already Met Sign-Up Goals - <AUTHOR> http://techcrunch.com/2012/07/29/kc-google-fiber-threshold-20-percent/

<comment><USER2> My fiberhood, Hanover Heights, is leading the pack in the race for fiber sitting at 21% pre-registration right now.

<comment><AUTHOR> Nice. The piece mentions something about TWC trying to push people into contracts, any idea if that's true?</comment></comment>


Bitcoin – The Magic of Mining - <AUTHOR> http://www.economist.com/news/business/21638124-minting-digital-currency-has-become-big-ruthlessly-competitive-business-magic

<comment><USER2> Mining is what will ultimately make Bitcoin fail. You want to give everyone a single vote so that the majority can agree on which transactions are valid and which are not. But because you don't want a central authority that checks ID documents you come up with the idea of mining - make having a vote in the Bitcoin network an expensive thing by requiring to buy hardware and then spend more money on electricity to keep you hardware alive. It's not really fair because if you happen to have a lot of money you can buy a lot of votes.

But the really bad thing is that you just made Bitcoin transactions pretty expensive - I got six Dollars per transaction for electricity only about a month ago. Even worse, processing more transaction will or should not lower these costs. If Bitcoin would really take off processing transactions worth billions every day, you really don't want to protect them by hardware and electricity costs only worth a few millions because the growing transaction volume will also increase the amount of money someone would be willing to spend to mess with your system. At least up to some limit you really want the total mining costs proportional to the transaction volume.

And from there down it goes. Bitcoin transactions are not cheap even if the current low transaction fees suggest it. As the block reward goes down all the costs of running the Bitcoin network will end up as transaction fees. And transaction costs of several dollars are the death of micropayments and Bitcoin adoption in the underdeveloped world, two of the most lauded arguments for Bitcoin. I am not dismissive of the idea of cryptocurrencies but Bitcoin with its proof of work scheme won't be the queen of the prom.

<comment><USER3> Your math is wrong, making your entire premise/argument invalid. A transaction costs $0.60 of electricity as of right now:

150000 kilowatt (power consumption of the global Bitcoin network [1]) ÷ (3600 (sec/hour) * 7 (transaction/sec)) = 6.0 kWh/transaction

The worldwide average price of 1 kWh is $0.10, so a transaction costs $0.60 in electricity to be processed by the network.

Also, the 7 transaction/second limit comes from the current 1MB block size limit which was chosen by agreement. It will be increased in the near future. If it is raised to, say, 10MB this would allow 70 transaction/sec, hence reducing the electricity cost of a transaction down to $0.06.

[1] [http://www.eetimes.com/document.asp?doc_id=1323522](http://www.eetimes.com/document.asp?doc_id=1323522) \- the global hashrate has increased by 50% since this article was written (~200 petahash/sec in August 2014, up to ~300 petahash/sec today) but at the same time hardware efficiency (hash/sec per watt) has increased, so the ballpark number is correct

<comment><USER4> Where do you get 150 000 kW? Even assuming all the miners are the best I could find (Achilles lab series) [1] that comes to 190000kW based on current hashrate [2].

Your transactions/second is also bit off. Right now based on blockchain.info the highest transaction day had 115787 transactions [3]. And that day the backlog of unconfirmed transactions got as high as almost 6000 unconfirmed transactions [4]. It doesn't matter at all if the network can "theoretically" support 7tps if it chokes at 1.3tps

That brings the actual kWh cost into 40kWh/transaction and up to the same ballback as what GP had.

Based on the arguments on forums right now it looks that increasing the block size is impossible. Because that would hard fork the blockchain.

When new coins are no longer being awarded to miners then people will have to start to pay the transaction fees themselves. Right now the mining is subsidized by what basically amounts to printing money and thus effectively is a small inflationary tax to everyone using bitcoin.

[1] [https://en.bitcoin.it/wiki/Mining_hardware_comparison](https://en.bitcoin.it/wiki/Mining_hardware_comparison)

[2] [https://blockchain.info/charts/hash- rate](https://blockchain.info/charts/hash-rate)

[3] [https://blockchain.info/charts/n-transactions](https://blockchain.info/charts/n-transactions)

[4] [https://imgur.com/GAklIdZ](https://imgur.com/GAklIdZ) The most delicious moment was not screencapped, but this is quite close. Even as this was happening the miners happily issued small blocks (500kB and less).

<comment><USER5> The network never "choked" at 1.3tps. There are peaks of activity near the theoretical max of 7 tps (check for blocks close to 1MB in size). There are thousands of unconfirmed transactions because their senders chose to include fees that are too low (or no fee at all), so miners decide to not process them.

> When new coins are no longer being awarded to miners then people will have > to start to pay the transaction fees themselves

That's not how it works. People (senders) already pay the transaction fees themselves.

<comment><USER4> 7tps is achievable only when every transaction has a single input and a single output. Real transactions are not like that, not by far.

People do not include enough transaction fee. I just clicked open a block with most transactions on the recent list on blockchain frontpage [https://blockchain.info/block/000000000000000017f4d893e29b1e...](https://blockchain.info/block/000000000000000017f4d893e29b1e5b0ba5d65d0416aed997afbf836c63f17c)

+.1715506 worth of transaction fees. That's by far not enough to support a decent mining rate. In order to support current mining rate a single block must have roughly 25BTC wort of transactions fees.

</comment></comment></comment></comment></comment><comment><USER6> That's a good article on Bitcoin mining.

Last week a big cloud mining operation, CEX.io, shut down. ([http://www.coindesk.com/cex-io-halts-cloud-mining-service- du...](http://www.coindesk.com/cex-io-halts-cloud-mining-service-due-low- bitcoin-price/)) The price of Bitcoin has dropped to the point that their operation was unprofitable.

Because the total weekly reward to all miners is fixed, all miners are in direct competition. If mining effort doubles, return on mining investment halves. The big operations are starting to hit that limit. The little guys hit it a long time ago.

</comment><comment><USER7> guys here in africa ze are starting to accpt bitcoin and i think this will have a positive effect on the coin [http://techunzipped.com/bitcoin- conference-africa/](http://techunzipped.com/bitcoin-conference-africa/)

</comment><comment><USER8> [https://www.google.com/search?q=Bitcoin+%E2%80%93+The+Magic+...](https://www.google.com/search?q=Bitcoin+%E2%80%93+The+Magic+of+Mining&oq=Bitcoin+%E2%80%93+The+Magic+of+Mining&aqs=chrome..69i57j69i64.239j0j7&sourceid=chrome&es_sm=122&ie=UTF-8)

<comment><USER9> Thank you.

</comment></comment><comment><USER3> _" last year it performed even worse than the Russian rouble and Ukrainian hryvnia"_

A number of journalists have relayed this claim lately, but I find it disingenuous as it avoid talking about the real reason (volatility) and it hides the big picture (Bitcoin is up 3200% over the last two years [1]).

Otherwise, this is a good article about mining. But one comment I would like to make is that people, like this author, sometimes claim Bitcoin's mining consume a lot of electricity. But compared to what? It is fair to compare it to the many data centers owned and operated by credit card processors, banks, and all sorts of financial companies, but only to the portion of these data centers that fulfill a role roughly comparable to Bitcoin: processing transactions, verifying fraud, etc. Let's do some math: North American data center market power consumption is about 12 gigawatt [2]. I don't know what the world data center power consumption is, but let's assume ~3x that, or 30 gigawatt [3]. Let's assume that 1/3 of these data centers belong to financial companies, so 10 gigawatt are consumed by financial data centers. If half of these data centers are used to process transactions and for anti-fraud purposes, that's 5 gigawatt. By comparison, Bitcoin's mining operations worldwide are estimated to consume 150 megawatt [4]. So Bitcoin mining uses 3% of the electricity of what financial companies use for similar purposes.

[1] From $6 in January 2013 to $200 as of today: [http://bitcoincharts.com/charts/bitstampUSD#rg730ztgSzm1g10z...](http://bitcoincharts.com/charts/bitstampUSD#rg730ztgSzm1g10zm2g25zl)

[2] [http://www.datacenterdynamics.com/focus/archive/2014/01/15-g...](http://www.datacenterdynamics.com/focus/archive/2014/01/15-growth- forecast-north-america-colocation-market-2014-0)

[3] 30 gigawatt is also approximately in line with the often quoted estimate that data centers use ~1% of the world's electricity (~1% of 2500 gigawatt).

[4] [http://www.eetimes.com/document.asp?doc_id=1323522](http://www.eetimes.com/document.asp?doc_id=1323522) \- the global hashrate has increased by 50% since this article was written (~200 petahash/sec in August 2014, to ~300 petahash/sec today) but at the same time hardware efficiency (hash/sec per watt) has increased, so the ballpark number is correct. In fact the economist article also estimates it at ~135,000 average american homes, or 168 megawatt (1 average home = 1250 watt).

Edit: @the_mitsuhiko: By definition, "volatility" is a price variation over time, regardless if it is consistent or not.

<comment><USER10> In all these discussions of Bitcoin's price over N months, I don't see anyone consider this: 2 years is 44% of its tradable life (first trades on Mt. Gox were in July 2010). You might as well talk about Apple's performance since 2000, which is 44% of its tradable life. In which case, you see similar returns (almost 3000%)

So if Bitcoin goes down to $30, that's an amazing investment, right? After all, that's a 500% ROI!

<comment><USER11> Nobody talks about "percentage of tradable life" because this is a pointless metric. You don't see banks publishing prospectus saying "this investment gained x% over y% of its tradable life". %/year is what matters to all investors.

> So if Bitcoin goes down to $30, that's an amazing investment, right? After > all, that's a 500% ROI!

Absolutely. Buying at $6 in january 2013, and selling even at $30 would be a 500% ROI and a great investment over 2 years. What is your point?

<comment><USER10> "%/year is what matters to all investors"

Exactly. Only one in Bitcoin in January 2013 were those who were really deep in the community. Investors don't care what the price was before they purchased.</comment></comment></comment></comment>


Get that job at Grab - <AUTHOR> https://firstname.lastname@example.com/get-that-job-at-grab-eea6de1d8421 <comment><AUTHOR> Basically Steve updated his 10 year old GTJ@Google post for his new company, but there are some interesting discussion points.

I just don't understand how he can say that Google runs off of it's reputation in hiring, and yet Steve still insists even senior engineers read Skiena and do the tired old DS/algos-style questions.</comment>


Silicon Valley cracks government with Palantir - <AUTHOR> http://www.transcapitalist.com/transcapitalist/2009/8/28/silicon-valley-meets-government-with-palantirs-collaborative.html

<comment><USER2> I can tell you guys, the developers working on the government software at Palantir, have the best job of any of us.</comment>


Carp: A statically typed Lisp, without a GC, for real-time applications - <AUTHOR> https://github.com/carp-lang/Carp <comment><USER2> a recent discussion, [https://news.ycombinator.com/item?id=15778530](https://news.ycombinator.com/item?id=15778530)

</comment><comment><USER3> This is insanely cool. To me, once I learned Lisp (Clojure and then Racket), it kind of gave me this "OMG why isn't every language like this????" feeling.

I wonder if Carp could fair well with a more academic, heavy-processing sector....

<comment><USER4> > I wonder if Carp could fair well with a more academic, heavy-processing > sector....

Could you expand on this? I'm not sure I understand your comment.

<comment><USER3> Academia, in my experience, has a tendency to use more theory-heavy languages (Haskell, OCaml, and of course Lisp), or the "easy-for-engineering" languages, like R or Matlab. When I used to work for a university, our stuff was done almost exclusively with Haskell.

This is fine, but a lot of academic work (bioinformatics, video processing, advanced statistical analysis, etc...) can be very computationally heavy, leading to a lot of academics and post-docs writing some ad-hoc C++ in order to squeeze out better performance.

What I was suggesting is that, since Carp might have better performance characteristics for more CPU bound tasks than something like, say, Racket, it might satisfying the niche of academic-friendly languages.

</comment></comment></comment><comment><USER5> Really well done. The lang design, the docs: intend is clear in every case and very on point.

I've never been a fan of lisps, but that has more to do with the common lack of strong typing discipline, than that it was a syntax issue. Currently I'm using Haskell a lot.

But this lisp is a breath of fresh air to my type-loving brain.

Maybe I've overlooked them, but what about higher kinded types and reflecting purity at type level? Are they not-in-and-never-will-be-by-design, or maybe- if-someone-implements, or on-the-road-map?

<comment><USER6> Have you looked at Shen[1] at all? It is a lisp dialect with a reasonably full featured type system[2]

1: [http://www.shenlanguage.org/](http://www.shenlanguage.org/)

2: [http://www.shenlanguage.org/learn- shen/index.html#9%20Types](http://www.shenlanguage.org/learn- shen/index.html#9%20Types)

<comment><USER7> Is the open source version of Shen suitable for production use? It's not clear to me how actively it's developed or how much it differs from the "professional" version. The website suggests it lags far behind, but I recall there being an acrimonious split between the original creator and the open source community.

</comment></comment></comment><comment><USER8> Any discussion about real-time Lisp is incomplete without a mention of Snd-RT: [http://archive.notam02.no/arkiv/doc/snd- rt/](http://archive.notam02.no/arkiv/doc/snd-rt/) so I'll just drop that here ;)

It's very ground-breaking work imho that is unfortunately very poorly known/cited, having been presented mainly to the computer music community, but it represents a real-time garbage-collected Scheme.

</comment><comment><USER9> It's really nice to see Clojure syntax being adopted in newer lisps.

<comment><USER10> Well, I suppose it's better that they re-use someone else's gratuitously different syntax than invent their own gratuitously different syntax.

<comment><USER11> I think most modern programmers prefer explicit destructuring and taking an element from a collection by its key rather than excplicitly traveling node links using car and cadr. The 'original' lisp has some really arbitrary naming conventions. Languages are cognitive tools and as such they should be able to evolve, rather than dogmatically stick to a specific formulation laid down in the formative years of a field.

It does not manner how you name your tokens or how you choose to destruct your data structures. It's still lisp.

<comment><USER6> I disagree that Clojure's AST changes are gratuitous. Rich has repeatedly provided his reasons for them. You may think they are bad reasons, but it's not like he just said "ZOMG there are too many parens!"

That being said, I tend to use destructuring in common-lisp, and if you are taking an element from a collection by using c*r then you are probably doing it wrong.

Optima has more complete support for destructuring, but this works just fine in CL with out any libraries:

        (let ((some-plist '(:foo 1 :bar 2)))
          (destructuring-bind (&key foo &allow-other-keys) some-plist
            foo))

<comment><USER12> And while it didn't make it into the Common Lisp version of LET, there were versions in earlier dialects that supported destructuring. For example, the Maclisp reference manual's description of LET[0] says:

It is permissible to place an s-expression pattern in place of a symbol in the (sym init) form of an element of the bvlspec. The symbols in the pattern will become bound to the matching elements of the initialization (see DESETQ). This kind of pattern-matched assignment is called destructuring.

        (let (((a b) '(1 2)))
          (cons b a))
        => (2 . 1)

0: [http://www.maclisp.info/pitmanual/contro.html#5.6.1](http://www.maclisp.info/pitmanual/contro.html#5.6.1)

</comment></comment></comment></comment></comment><comment><USER13> The readme is very terse, but exciting. Can anyone elaborate about the ownership model?

<comment><USER14> The page on syntax and semantics says "To learn more about the details of memory management, check out Memory.md", linking to [https://github.com/carp- lang/Carp/blob/master/docs/Memory.md](https://github.com/carp- lang/Carp/blob/master/docs/Memory.md)

</comment></comment><comment><USER15> Whoa time to try this out, this seems awesome. (nb: c++ guy who love clojure)

</comment><comment><USER16> How and when does it clean up memory allocated for closures?

<comment><USER17> Presumably it's up to you to manage that?

</comment></comment><comment><USER18> Will be interesting to see how compiling to C affects debugging in the real world. LLVM is nice as a target, since it allows you to map generated IR blocks to source locations. Of course, it also means that the compiler needs to link to all of the LLVM libs, which is a bit of a hassle too. (I've found this when working on a Clojure->LLVM compiler bootstrapped from Clojure).

<comment><USER19> You can map locations in generated C code to locations in some other file, too. Standard C has a pragma for it:

        #line <num> "filename"

or, if the filename is the same as the previous pragma, you can omit it from the pragma:

        #line <num>

This pragma is used to inform the compiler of what information it should use when displaying error messages and such. I think it's meant to be used by the C preprocessor, but the preprocessor isn't _required_ to use it, and other programs aren't _prohibited_ from using it.

You might wind up generating a lot of these, but they're really easy to generate as long as you preserve that information all the way through compilation (which I'd assume you'd have to do for LLVM IR regardless).

<comment><USER18> Interesting, I wasn't aware of the #line directive, thanks!

Yes, you would need to keep track of the source locations for each node in the AST. There is a nice example in the LLVM Kaleidoscope tutorial here: [https://llvm.org/docs/tutorial/LangImpl09.html](https://llvm.org/docs/tutorial/LangImpl09.html)

<comment><USER20> Bison and lex use #line to make generated C/C++ code (lexer, parser) debuggable, or at least their GNU implementation does, I don't know about other implementations.

</comment></comment></comment></comment><comment><USER21> I've been wanting a true statically-typed Lisp for a while. Very excited to try this for keyboard firmware!

<comment><USER22> Typed Racket has been around for a while, is that not close enough to a lisp for you?

<comment><USER21> I tried using it for some small projects, and it was really fun but seemed to not mesh well with the rest of the Racket ecosystem.

</comment></comment></comment><comment><USER23> > _(defn_

What's wrong with "def"?

<comment><USER24> At least in Clojure, (defn my-function [] ...) is syntactic sugar for (def my- function (fn [] ...)), removing one level of nesting.</comment></comment>


Cars All but Banned on One of Manhattan's Busiest Streets - <AUTHOR> https://www.nytimes.com/2019/10/03/nyregion/car-ban-14th-street-manhattan.html <comment><USER2> > "I think it's extreme and there should be a compromise. Everybody pays taxes > — not just the people in the buses."

I would make the opposite argument actually. Car drivers pay the same amount of taxes despite taking up more space on the road, causing more accidents etc. It's an unfair subsidy loophole that is finally getting plugged.

<comment><USER3> Cars pay for the space they occupy through fuel, excise, and sales taxes.

Buses, on the other hand, are a loss-leading and highly subsidized form of transport.

<comment><USER4> > Cars pay for the space they occupy through fuel, excise, and sales taxes.

Your statement is absurd. You're arguing that something should have the right to occupy the public space and deprive others from using it just because the owner bought it and spends money on fuel.

<comment><USER5> The quoted text is meant to be read as "fuel taxes, excise taxes, and sales taxes."

</comment></comment></comment></comment><comment><USER6> just walked across 14th today for lunch, it was beautiful. the only traffic is buses, and maybe the odd truck. there are cops posted -- because the street is so empty, it's tempting to jaywalk without looking for an oncoming bus.

as another commenter said, the drivers brought this onto themselves. i think the impact of uber driving around waiting for a ride, + booked ubers double parked waiting for the charge to arrive, adds significantly to congestion. without getting into the uber/taxi debate, you could just see (and hear the honking) how difficult it was for the buses to get through even during normal traffic.

another quiet change that happened nearby, is the closure of union square w between 14th & 17th. theres an extremely high amount of pedestrian traffic, and near the edges of the square there's intersections that would get pretty dicey. now it's much, much better. to be fair, ny drivers are decent, but there's just too much volume (and pedestrians looking down at their smartphones). i'm sure people got hit on an almost daily basis. ironically, i'm more afraid of bicyclists hitting me than cars. they simply do whatever they want.

but still, i firmly believe these changes are a huge positive overall.

<comment><USER7> > ironically, i'm more afraid of bicyclists hitting me than cars. they simply > do whatever they want.

I'm in Seattle, not NYC, but this is an almost daily nuisance for me, both as a driver and as a pedestrian. Cyclists in general seem to have an attitude like rules and laws don't apply to them. I see them blowing red lights, disobeying all-way stops, and nearly running over people all the time.

<comment><USER8> I think this is the case because in the US only extreme cyclists dare use the road at all. When cycling becomes sufficiently safe that normal people do it, the median cyclist becomes much friendlier to other people on the road.

<comment><USER9> I think that's just wishful thinking. I'm from Melbourne where cycling is pretty common (although not as hectic as in Holland). The cyclists here are still pretty rude.

<comment><USER10> There's a difference between rude and illegal. I think the original commenter was speaking more about illegal behavior leading to accidents.

In my experience in cities where cycling is built into the architecture of the city, most do tend to follow the road rules. However, a pedestrian might still find it rude if a cyclist were to pass close enough to brush shoulders, or a driver might find it rude for a cyclist to lane split.

From my perspective that kind of "rudeness" is just part city life, though, it's not really something exclusive to cyclists.

<comment><USER7> Yeah, I was referring to outright illegal behavior. I really dislike the "rules don't apply to me" attitude - seems so entitled.

On the rudeness aspect though, I do find cyclists in general pretty rude. I've even seen cyclists that seem to outright seek confrontation by putting themselves in situations that are unfavorable to them. For example, the other day I observed a challenging traffic situation and a driver had to stop mid turn at a corner. A cyclist was coming and saw the whole thing happen, but they still positioned themselves such that a "hook" accident could occur once things started moving again. As soon as the car started moving to complete their turn, the cyclist also moved forward and started arguing with the driver. It looked pretty clearly premeditated.

</comment></comment></comment></comment></comment></comment><comment><USER11> I'm actually thrilled about this idea, and I hope it spreads to other cities.

The key to effective mass transit is not the type of equipment (train vs. bus) or the surface (rails vs. asphalt). It is the right-of-way, plain and simple. All other things being equal, a transport that has right-of-way, unimpeded by cross traffic, will be faster than a transport that has to deal with stop lights, cross traffic, etc.

That being said, mass transit can be extremely expensive if you take too many pains to construct the right of way off the surface. Digging is expensive and dangerous. Building elevated platforms is also more expensive, and often unsightly.

Now let's compare the means of traction: rails provide only fixed paths. They're relatively time-consuming to fix if they break. And if there's an equipment breakdown, if there aren't redundant paths with effective switching, it can cause a head-of-line blocking problem (comparable to a message queue). Meanwhile, tires are cheap and safe, while steering can easily avoid obstacles and other dangers. And repairing asphalt streets is relatively inexpensive.

So: we have good road technology. We have wide-enough arterial roads, many of which are already redundant. We have good-enough signaling technology now to create a virtual right-of-way (by setting lights to red before the vehicle crosses). Buses are pretty reliable these days, and far cheaper to manufacture than train cars. They can also be outfitted to be quite nice inside.

So, to me, dedicated bus thoroughfares using existing streets are a no- brainer. They win on cost, they win on effectiveness, and they win on time-to- market.

I can totally see 1 out of every 4 streets being used in major cities as dedicated bus thoroughfares as a viable alternative to building super- expensive and relatively unreliable transit alternatives. I've often said I'd love to see it happen in San Francisco. (The 1-in-4 idea being an approximation for most people to walk to their ultimate destination in a reasonable amount of time, but it's obviously adjustable according to block size, geography, etc.)

(Footnote: for those who maintain residences on the impacted streets, there should be various accessibility exceptions.)

<comment><USER3> > _I can totally see 1 out of every 4 streets being used in major cities as > dedicated bus thoroughfares as a viable alternative to building super- > expensive and relatively unreliable transit alternatives._

Of course that would itself be incredibly expensive. Roughly 1/4 the cost of all the roads in a city is a tremendously large amount of asphalt to maintain exclusively for buses.

The local businesses will also really enjoy being derelicted.

<comment><USER11> I'm operating under the assumption that the roads in question are already built and that the ongoing cost to maintain them is identical or less than the ongoing cost to maintain them if they were open to all traffic. In other words, no worse than the status quo.

<comment><USER3> That doesn't actually change the cost of the policy.

Repurposing an asset you spent $X to build is the same as spending $X on a new asset for that purpose, minus any depreciation you took up till that point.

To your point, if road costs continue to be the status quo, then 1/4 of what you spent on roads should now be covered by bus fares. That would make the buses impossibly expensive.

I'm sure that people who like riding public transit buses would love this policy, because your taking an already highly subsidized (loss leading) form of transportation and making it an order of magnitude more subsidized by giving them free private roads to ride on.

<comment><USER11> Perhaps you have a different understanding of what "expensive" means than the generally accepted definition. Expensive generally refers to the outlay (the expense), not the income, or the net income, or any other financial metric.

> repurposing an asset you spent $X to build is the same as spending $X on a > new asset for that purpose

Does GAAP agree with your claim?

<comment><USER3> Yes, GAAP accounting considers the payment for building the road as purchasing an asset. Cash account goes down, road assets go up.

The depreciation _expense_ for using the road accrues to whoever/whatever it is being used for.

If you allocate roads exclusively for buses, buses need to cover the cost of maintaining the road.

Today buses can't even cover the cost of running the buses.

<comment><USER11> > Yes, GAAP accounting considers the payment for building the road as > purchasing an asset. Cash account goes down, road assets go up.

True.

> The depreciation expense for using the road accrues to whoever/whatever it > is being used for.

False. Depreciation happens no matter what. The accountants don't care how it's used. The taxing entity may care if you want to obtain a deduction for the depreciating asset as a cost basis, but that's not an accounting question.

> If you allocate roads exclusively for buses, buses need to cover the cost of > maintaining the road.

No they don't. Ideally, maybe; but that's a political question, not an accounting question.

</comment></comment></comment></comment></comment></comment></comment><comment><USER12> They should extend the sidewalks so there's only two bus lanes and build some protected bike lanes there. Make this permanent. Drivers will figure out a way. I hope more cities do more of this. Cities can change. Just look at Amsterdam now compared to the seventies. I have always and still do drive around everywhere due to where I live, but this is the only way to change things. Just do it. Hopefully the judges throw out the frivolous lawsuits that prevent changes for the better like this.

</comment><comment><USER13> I feel like the drivers did it to themselves. New York tried dedicated bus lanes and the drivers continued to use the dedicated bus lane any time police presence wasn't obvious.

<comment><USER14> Agreed. I've started taking the M15 SBS in the last month and it would be great except the driver has to honk and weave around vehicles stopped in the bus lane on almost every block.

<comment><USER15> Could have been solved, first time $50 fine, and second time license revoked for a month.

People will learn quickly

<comment><USER16> UK has automatic bus lanes cameras in a lot of places and a database of licence plates used by buses - if your car is not on the list you get an automatic ticket. Also works pretty well.

<comment><USER17> NYC is getting these too, so hopefully that helps:

> The MTA announced that it will ramp up its fines for bus lane blockers > captured through its new automated bus-mounted camera system. Motorists who > defy the new rules after a 60-day warning period will be hit with a $50 fine > that will increase with every offense up to $250. That will begin with the > M15 SBS on October 7, with the M14 and B44 due to be equipped with the > automated cameras by the end of November.

[https://ny.curbed.com/2019/10/2/20895121/14th-street-dot- mta...](https://ny.curbed.com/2019/10/2/20895121/14th-street-dot-mta-busway- launches-this-week)

</comment></comment></comment></comment></comment><comment><USER18> Once in a while, the Champs-Elysées in Paris are closed to cars on Sunday. When there were the yellow-vest protests, a large part of central Paris was closed to cars on Saturday too.

It was pleasant to walk in the streets that time, the city looked more human, with less noise, less honk, less stress. However, some cyclists and escooter drivers are a bit uneducated, many of them don't respect stops or signs, they don't slow down, and would pass at 2 cm from you at 20km/h like you do not exist

Other than that, I'm 100% for banning cars and petrol-based motorcycles from big capital cities around the world.

</comment><comment><USER19> Honestly, I am a big fan of this. I lived in Calgary this summer, and downtown they have a dedicated street for the train, busses, and emergency vehicles. No regular vehicles are allowed to drive down this street.

It's genius. The train lines are above ground so the lines were cheaper to manufacturer, Emergency vehicles can get across downtown very quickly, and busses also don't have to deal with congestion.

</comment><comment><USER15> All speculation, but isn't this how traffic management should always be done?

Shouldn't traffic be modeled and leave stats to just simply determine what roads should be cars only, trucks, buses, etc?

<comment><USER20> Simulating road traffic is a fertile academic and applied field. But that is by far the easiest part. It's much harder to change the rules because then humans are involved.

</comment></comment><comment><USER21> This is a great idea, and would make sense in many other American cities.

</comment><comment><USER22> Good luck New York with Andy Byford! I was never impressed with the man and was happy to see him leave Toronto.</comment>