A quarter century of satellite imagery

 Google, Mapping  Comments Off
May 212013
 

Picture of Earth through time

In collaboration between USGS, NASA and TIME, Google released a quarter century of satellite imagery to see how the world has changed over time.

The images were collected as part of an ongoing joint mission between the USGS and NASA called Landsat. Their satellites have been observing earth from space since the 1970s—with all of the images sent back to Earth and archived on USGS tape drives that look something like this example (courtesy of the USGS).

We started working with the USGS in 2009 to make this historic archive of earth imagery available online. Using Google Earth Engine technology, we sifted through 2,068,467 images—a total of 909 terabytes of data—to find the highest-quality pixels (e.g., those without clouds), for every year since 1984 and for every spot on Earth. We then compiled these into enormous planetary images, 1.78 terapixels each, one for each year.

Be sure to check out the Timelapse feature on Time.

Geography of hate against gays, races, and the disabled

 Mapping, Twitter  Comments Off
May 132013
 

Homophobic tweets

In a follow-up to their map of racist tweets towards Barack Obama, the folks at Floating Sheep took a more rigorous route to get around the challenges of sentiment analysis. Over 150,000 geotagged tweets against races, sexuality, and disabled were manually classified and mapped.

All together, the students determined over 150,000 geotagged tweets with a hateful slur to be negative. Hateful tweets were aggregated to the county level and then normalized by the total number of tweets in each county. This then shows a comparison of places with disproportionately high amounts of a particular hate word relative to all tweeting activity. For example, Orange County, California has the highest absolute number of tweets mentioning many of the slurs, but because of its significant overall Twitter activity, such hateful tweets are less prominent and therefore do not appear as prominently on our map. So when viewing the map at a broad scale, it’s best not to be covered with the blue smog of hate, as even the lower end of the scale includes the presence of hateful tweeting activity.

Hard to believe this stuff is still around. It looks like I might want to stay clear of some parts of Virginia.

Cicada insects out to play after 17 years

 Mapping  Comments Off
May 102013
 

Cicada

This is my first time hearing about this, probably because it only happens every 17 years. After 17 years of development in the ground (getting nourishment from tree roots), the Cicada insects are starting to swarm on the east coast. Hundreds of millions of them mate, make a lot of noise, and then die. Adam Becker and Peter Aldhous for New Scientist mapped data maintained by John Cooley and Chris Simon from the University of Connecticut to show the cycles of the Cicada.

There are 17-year broods, which is what's happening now, and there are 13-year broods, with the next one expected next year in Louisiana.

Click the play button on the top right to see the various broods appear over time, and be sure to turn on the audio (in the left panel) for added flavor. [Thanks, Peter]

Data Points: Visualization That Means Something is available now. Order your copy.

Exploration of how much geography is needed in metro maps

 Mapping  Comments Off
May 092013
 

Removing geometry by Fathom

Terrence Fradet of Fathom Information Design ponders whether metro maps suffer or benefit by leaving out geography. Geographic accuracy is good, but sometimes it can confuse your audience.

Just how important is it that metro maps represent geography? This piece came from an interest in how metro maps over the past century have tiptoed between geographic and topological representations—topological meaning to forgo all spatial integrity and instead represent the connectivity of a specific environment.

Data Points: Visualization That Means Something is available now. Order your copy.

YouTube Trends map shows most popular videos by region

 Mapping, videos, youtube  Comments Off
May 082013
 

YouTube Trendsmap

I don't know about you, but when I go to YouTube, I check my subscriptions and then look at what videos are currently popular. Because you know, it's important to stay up to date on the most current news about kittens, people getting caught doing weird things, and movie trailers. The YouTube Trends Map is another way to see what's popular, but from a geographic and demographic point of view.

As you'd expect, the map shows the currently most popular video in a region, based on shares or views, which looks like a lot of noise at first. Look a little closer though, and there are some interesting spots.

For example, looking at it now, the most popular video in the 12 to 24 year old range is a clip from Family Guy. In contrast, move to the older age brackets, and the most popular is a trailer for True Blood. The most popular clip in Oklahoma City is Kevin Durant's winning shot from Sunday's Oklahoma City Thunder game.

Finally, the map is linked with a stacked bar view, which shows the breakdown just by demographic.

YouTube trends stacked bars

I like it.

[via @viegasf and @wattenberg]

Data Points: Visualization That Means Something is available now. Order your copy.

Map shows street quality in Los Angeles

 Mapping  Comments Off
May 072013
 

Los Angeles street grades wideview

Nevermind the horrible traffic in Los Angeles, where it takes a several hours to get somewhere when it should only take thirty minutes. The road quality isn't so great either. Using data from the Los Angeles Bureau of Street Services, which scores street segments on a 100-point graded scale, Ben Poston and Ben Welsh for The Los Angeles Times mapped road quality in the city.

Red represents segments with an F grade, which means resurfacing or reconstruction is required, and green are segments with A grade, which mean no cracking and no maintenance required. Yellow is everything in between. Jump to a specific area via text entry and/or see the data in aggregate, by neighborhood or council district.

The streets don't look great almost any way you look at it.

Data Points: Visualization That Means Something is available now. Order your copy.

Fixing bus routes using mobile data

 Mapping, Mobile  Comments Off
May 032013
 

Transportation map by IBMIn parts of the world where there are few smartphones and GPS-enabled devices, transportation architecture has to be designed based on less granular resources, such as surveys, which can result in rough estimates. IBM researchers are looking into how data from simple cell phones can be used instead to see how people move.

The IBM work centered on Abidjan, where 539 large buses are supplemented by 5,000 mini-buses and 11,000 shared taxis. The IBM researchers studied call records from about 500,000 phones with data relevant to the commuting question...

While the data is rough—and of course not everyone on a bus has a phone or is using it—routes can be gleaned by noting the sequence of connections. And IBM and other groups have found that these mobile phone “traces” are accurate enough to serve as a guide to larger population movements for applications such as epidemiology and transportation.

[via @krees]

Data Points: Visualization That Means Something is available now. Order your copy.

History of San Francisco street names mapped

 History, Mapping  Comments Off
May 012013
 

History of SF street names

Where do street names come from? Sometimes there's actual history behind a name, and other times a street just needed a label, so someone pretty much pulled one out of a hat. For the former, there can be some interesting stories at work. Web developer and Knight-Mozilla fellow Noah Veltman mapped the history of street names in San Francisco under this premise. Just click on a blue street in the interactive and information pops up.

Data Points is in the wild. Grab a copy.

 Older Entries