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This map shows how low-density sprawl makes climate change worse

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Most Americans surveyed in a recent poll (including a majority of city dwellers) believe that high density is bad for the environment. In reality, however, sprawl is probably much worse for creating carbon dioxide emissions.

As the map below from the University of California Berkeley’s CoolClimate Network shows, large metropolitan areas are substantial contributors to carbon dioxide emissions throughout the Mid-Atlantic (CoolClimate’s data show similar trends throughout other parts of the country). But the volume of emissions varies widely within metropolitan areas.

Source: https://coolclimate.berkeley.edu/maps

On the map, lower emission green spots appear in central Richmond, the District of Columbia, Baltimore, Philadelphia, Northern New Jersey, and New York City, as well as in a number of rural communities outside of metropolitan areas. Higher emission orange and red areas dominate in the suburban areas, however.

According to the researchers’ data, household income, vehicle ownership, and home size make up the biggest predictors of emissions. In other words, in low-density areas, more driving, higher energy use from larger houses (as well as housing type, and higher consumption increase greenhouse gases.

This means suburban ZIP codes can emit up to four times the household emissions of their urban counterparts –enough to more than wipe out any gains from lower C02 emission-households in higher density areas.

The researchers caution that increasing density is not necessarily a panacea, but their work highlights the correlation between land use and household greenhouse gases. In fact, other researchers such as Brookings, have estimated that meeting the United States’ 2030 emissions goals will be impossible without changing our cities – even with widespread electric vehicle adoption.

It is worth making a distinction between ‘suburban’ (low-density development) and ‘suburbs’ (jurisdictions outside of a central city), since sprawl doesn’t begin or end at city lines. Some of Greater Washington’s densest neighborhoods are not in Washington, DC at all, and some of the inner ‘suburbs’ have lower emissions per household than areas with sparser development in Northwest DC, according to the data.

C02 emissions in the Washington region correlate with low density. Source: https://coolclimate.berkeley.edu/maps

The CoolClimate’s data are from 2013, and therefore does not provide the most up-to-date information. Despite this, sprawl has continued through the last decade (albeit at a possibly slower rate), and America’s greenhouse gas emissions from cars have remained stubbornly high.

Top image: Low-density developments that prioritize detached single-family homes and automobile use disproportionately contribute to climate change. Image by La Citta Vita licensed under Creative Commons.

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bjtitus
53 days ago
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Denver, CO
acdha
53 days ago
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Washington, DC
freeAgent
53 days ago
I notice that these charts are per household and not per capita. I assume household size in the suburbs tends to be larger than in cities, which my be skewing these charts. IMO, they should show per capita.
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When the Mediterranean Sea Dried Up

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About 5.9 million years ago, due to a combination of tectonic movements and changes in climate, the Mediterranean Sea mostly dried up for over 600,000 years. The Messinian salinity crisis may have raised global sea levels by as much as 33 feet and decreased the salinity of the world’s oceans, raising the freezing point. And then, much more suddenly, it was refilled in less than two years in the Zanclean Flood.

Two years to refill the whole Mediterranean! Apparently the water level rose at 30 feet per day, fed by a river that carried 1000 times more water than the Amazon at velocities exceeding 88 mph. When the water reached a barrier near present-day Sicily, it flowed into the eastern basin via a mile-high waterfall in which the water was moving at 100 mph. The weight of so much water moving into the area so quickly would have triggered seismic activity, resulting in landslides that could have produced tsunamis with wave heights of 330 feet. So much wow!

Anyway, watch the PBS Eons video above for the whole story. And then check out this animation of what the drying up and the flood may have looked like.

P.S. For XKCD, Randall Munroe wrote a comic called Time that unfolded over a series of four months and was based on a future Zanclean-like flood. (via open culture)

Tags: geology   Mediterranean Sea   Randall Munroe   science   video
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bjtitus
134 days ago
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Reader’s Block

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I stumbled across this comic by Grant Snider this morning and realized that I am often afflicted by reader’s block but have never quite thought about it in that way, somehow.

Readers Block

Some of Snider’s reasons affect my reading more than others: too little time, too much TV, not enough sleep, crippling ennui, low curiosity. I’ve recently started to use an app to help me form some good habits and break bad ones, and one of my daily tasks is “read a book for 15 minutes”. I hit that target almost every day and when I do, I usually get in the groove and go for longer, sometimes an hour or more. This has revealed “too little time” and “too much TV” to be falsehoods that I no longer believe — “too much phone” I am still working on.

I’ve also stopped reading books that don’t grab me, as interesting as they may seem and as acclaimed as their recommenders insist. If I’m reading something and I find myself daydreaming or wanting to check my phone or switching to an episode of something on Netflix, that’s a sign that I should put it down and find another book. The only problem with this is that some of my favorite books (Infinite Jest for one) did not grab me in the beginning but picked up in a major way later, sometimes hundreds of pages in. Great books sometimes do not hand everything to the reader on a silver platter and the hard work they demand becomes part of their reward.

But my main two reader’s block problems persist. The first is represented by “low curiosity” in Snider’s comic — I read all day long for my work here on <a href="http://kottke.org" rel="nofollow">kottke.org</a> and when it comes time in the evening to wind down, more reading is often not something I can manage, especially with nonfiction (brain sometimes function at night not good). Reading right after I wake up has helped somewhat, but I typically have a logjam of tasks vying for my attention in the high-energy early morning and reading only occasionally wins.

The second thing is that I often get stuck between books. Part of it is the “overwhelmed by infinite possibility” factor — soooo much good stuff to read, how can you possibly choose what’s next? Succumbing to the temptation of other possible diversions or wavering in my disbelief of “too little time” becomes much easier when I’m not currently caught up in a story or someone else’s world view. Lining up your next read before finishing your current book is a possible solution, but that can be tough when you’re fully engaged in what awaits you in the closing chapters of your present literary love.

You can read more thoughts on reader’s block and how to tackle it from Stuart Jeffries, Emily Petsko, and Hugh McGuire. And if you and your preschooler are stuck looking for something new to read together, Snider has a new picture book out called What Color Is Night?

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bjtitus
934 days ago
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Tools lead culture change: Happy Birthday DevOpsDays

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bjtitus
973 days ago
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Tools lead culture change: Happy Birthday DevOpsDays
Denver, CO
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Beautifully Intricate Paintings of HIV, Ebola, and Other Molecules by Biologist David Goodsell

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For more than 25 years, biologist David Goodsell has been making scientifically accurate paintings and illustrations of the molecular structures of things related to HIV, cancer cells, ebola, Zika, diabetes, proteins, enzymes, and hundreds of other scientific and medical processes.

Since the early 1990s, I have been working with a type of illustration that shows portions of living cells magnified so that you can see individual molecules. I try to make these illustrations as accurate as possible, using information from atomic structure analysis, electron microscopy, and biochemical analysis to get the proper number of molecules, in the proper place, and with the proper size and shape.

Much of his work is available to use for free (with attribution) and is scattered across the web: the Molecule of the Month, Molecular Landscapes, Illustrations for Public Use. He has also published several books of his paintings, the most popular of which is The Machinery of Life. Science magazine recently profiled Goodsell and his work.

In addition to studying pictures of cells from high-powered microscopes, Goodsell relies on molecular structures from electron microscopy (EM), x-ray crystallography, and nuclear magnetic resonance spectroscopy to make his paintings, which show the often crowded and complex world of cells and the microbes that infect them. He even uses the known weights of molecules if that’s all he has so that he can at least draw, say, a correctly sized circle. “I’m a scientist first,” he says. “I’m not making editorial images that are meant to sell magazines. I want to somehow inform the scientists and armchair scientists what the state of knowledge is now and hopefully give them an intuitive sense of how these things really look — or may look,” he says.

May look?

“These pictures have tons and tons and tons of artistic license,” he says. “They’re just one snapshot of something that’s intrinsically superdynamic. Every time I do a painting, the next day it’s out of date because there’s so much more data coming out.”

Here’s a quick video profile as well:

All images are by David S. Goodsell, the Scripps Research Institute. (via alexandra kammen)

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bjtitus
977 days ago
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Beautifully Intricate Paintings of HIV, Ebola, and Other Molecules by Biologist David Goodsell
Denver, CO
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leah blogs: Ken Thompson's Unix password

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Somewhere around 2014 I found an /etc/passwd file in some dumps of the BSD 3 source tree, containing passwords of all the old timers such as Dennis Ritchie, Ken Thompson, Brian W. Kernighan, Steve Bourne and Bill Joy.

Since the DES-based crypt(3) algorithm used for these hashes is well known to be weak (and limited to at most 8 characters), I thought it would be an easy target to just crack these passwords for fun.

Well known tools for this are john and hashcat.

Quickly, I had cracked a fair deal of these passwords, many of which were very weak. (Curiously, bwk used /.,/.,, which is easy to type on a QWERTY keyboard.)

However, kens password eluded my cracking endeavor. Even an exhaustive search over all lower-case letters and digits took several days (back in 2014) and yielded no result. Since the algorithm was developed by Ken Thompson and Robert Morris, I wondered what’s up there. I also realized, that, compared to other password hashing schemes (such as NTLM), crypt(3) turns out to be quite a bit slower to crack (and perhaps was also less optimized).

Did he really use uppercase letters or even special chars? (A 7-bit exhaustive search would still take over 2 years on a modern GPU.)

The topic came up again earlier this month on The Unix Heritage Society mailing list, and I shared my results and frustration of not being able to break kens password.

Finally, today this secret was resolved by Nigel Williams:

From: Nigel Williams <<a href="mailto:nw@retrocomputingtasmania.com">nw@retrocomputingtasmania.com</a>>
Subject: Re: [TUHS] Recovered /etc/passwd files

ken is done:

ZghOT0eRm4U9s:p/q2-q4!

took 4+ days on an AMD Radeon Vega64 running hashcat at about 930MH/s
during that time (those familiar know the hash-rate fluctuates and
slows down towards the end).

This is a chess move in descriptive notation, and the beginning of many common openings. It fits very well to Ken Thompson’s background in computer chess.

I’m very happy that this mystery has been solved now and I’m pleased of the answer.

[Update 16:29: fix comment on chess.]

NP: Mel Stone—By Now

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bjtitus
985 days ago
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989 days ago
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990 days ago
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acdha
990 days ago
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beslayed
966 days ago
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jepler
990 days ago
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ha!
Earth, Sol system, Western spiral arm
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