Very cool motion graphic promo for National Geographic’s new year-long series, via Kat and seen at BrainPickings.
Archive for the ‘Mapping’ Category
Ascension Island: Like Easter Island, Ascension Island has lessons for the planet—cheerful ones (Economist)Monday, January 3rd, 2011
[Editor's note: Fun geo writeup of that spot of rock in the Atlantic near St. Helena. Thanks Derek!]
AT THE top of Green Mountain, the central peak of Ascension Island, there is a small pond, dotted with lilies, shadowed to one side by the fronds of a pandan tree. It is the only open body of fresh water on the island—and for a thousand kilometres in any direction. Around Dew Pond grows a grove of towering bamboo, beyond which the trade winds blow incessantly from the south-east. Within the grove the air is still and damp.
Along the trailing ridge of the summit are fig trees, Cape yews and a garland of remarkably vigorous ginger. Below, on the mountain’s lee side, trees and shrubs from all parts of the world spread down the hillside to a landscape of casuarina trees—ironwood, or she-oak—and thorny chaparral around its base. Even on the bleaker windward slope, grasses and sedges are dotted with Bermuda cedar and guava bushes. Above, the bamboo scratching at their bellies, are the clouds the trade winds bring; some days they cover the mountain top.
Once seen as too dry to be worth inhabiting, Ascension Island is becoming greener at an increasing rate. People are responsible. In part, their contribution was unwitting: the thorny mesquite that anchors a lot of the island’s scrub was introduced for a landscaping project just 50 years ago. But the forest on the peak of Green Mountain represents a deliberate attempt to change the island’s climate to make it more habitable. It is the centrepiece of a small but startling ecological transformation which is part experiment and part accident, part metaphor and part inspiration.
Ascension was discovered by the Portuguese in 1501. Just to the west of the mid-ocean ridge that separates South America’s tectonic plate from Africa’s, it is the top of a volcano which rises steeply from abyssal plains more than four kilometres below the surface of the ocean. The volcano made it above that surface only a million or so years ago, since when the island has grown to about 100 square kilometres. Before people arrived it was home to just a flightless bird, a land crab and no more than 30 species of plant, none as big as a bush. It was so barren and isolated that during the following three centuries of assiduous empire-building neither the Portuguese nor any other nation bothered to claim it. When Captain Cook passed by in 1775, Georg Forster—later to become renowned for his accounts of exploration—wrote it off as a “ruinous heap of rocks”, drearier even than Tierra del Fuego and Easter Island. But Forster’s naturalist father Johann saw something more promising:
Now on YouTube! This hour long documentary “takes viewers on a rollercoaster ride through the wonderful world of statistics to explore the remarkable power they have to change our understanding of the world, presented by superstar boffin Professor Hans Rosling, whose eye-opening, mind-expanding and funny online lectures have made him an international internet legend.” BBC4
Created by Reddit user JPalmz, this cartogram-like graphic uses the country shapes from a normal world map but relabels them according to population ranking. Click on image for larger version.
This app gets the job done: PDF Maps introduces a strongly played set of basic features and later versions promise to add more advanced features like layer visibility and feature attribute query. Professional cartographers can use the app to deliver custom cartography maps that leverage GPS to locate the map-reading customer with the magic blue dot. It’s certainly not an ArcPad, but it works on the iPad and you’ll find it fun to use (and the app price is right).
I quite enjoy Avenza’s new free PDF Maps iOS app, free and available now on the iTunes App Store for iPhone and iPad. I’ve been testing it for several months using both the beta and final release versions. I’ve used the app in my neighborhood, on a cross country road trip, and we’ve been using it to ground truth maps at at my day job. I’ve created my own GeoPDFs and used those from USGS and Avenza.
Besides myself, I setup two non-cartographers with an iPad (3g with gps) and several GeoPDFs depicting neighborhood-level street maps to field check in the Washington DC metro area. They were amazed at how easy it was to locate themselves on the map and make notes by dropping markers they bring back to the office for me to review. Because these particular maps include street labels, they don’t need to switch back and forth to Apple’s provided Google Maps app as they navigate.
The inaugural version is iOS only but the company has had requests for Android, Symbian, Blackberry and even Windows 7 Mobile. Expect an Android version next. Future iterations of the app may introduce a two-tiered, free-basic feature and pay advanced feature parellel versions, which seems reasonable to me. I’m also excited to see if a white-label version becomes available (much like the Flash SWF export out of Avenza’s MaPublisher plugin for Illustrator) that cartographers can use to brand the experience and pre-bundle their maps.
- View and load your own custom cartography maps and view them with GPS location
- Supports both Adobe/ESRI geospatial PDF maps and TerraGo/USGS GeoPDF® files.
- Access and interact with saved maps without the need for a live network connection
- Standard GSP app features: Plot way-points, enter attribute data and notes, measure distances and areas
- Standard iOS interface: Quickly view, zoom and pan maps using gestures (pinch, drag and flick, double tap)
- HD version for iPad same app as the basic version for iPhone, slightly reworked interface
- Does not currently support waypoint export, a key feature
- Does not currently support import of KML and GPX files
To create a GeoPDF, you’ll need ArcGIS 9.3.1+ to export from ArcMap with preserve coordinate system checked. Or use Avenza’s MaPublisher plugin for Illustrator (version 8.2+). You can also download thousands of GeoPDFs from USGS. Even though the USGS files use the TerraGo GeoPDF format specification (versus Adobe + ESRI’s), it will open and render in PDF Maps.app. Avenza also offers dozens of sample GeoPDFs linked from within the app to get you started (click Maps, then +, then From Avenza PDF Maps Library and browse the list).
Adding maps is as simple as dragging them to iTunes or attaching to an email (making it easy to send map updates to your field checker). Clicking on a PDF link on the iPhone or iPad now prompts to open in the app, as seen in the first screenshot above . Once opened in the PDF Maps app, it will take a few seconds to minutes to render, second screenshot above. Once open, several tools are available, the most important of which is simply the “locate me” triangle button on the map map view.
Even though it’s all about the PDF map you’re looking at, the app makes it convenient to open the same view in Maps.app to see Google’s version of reality for cross checking, especially using the satellite map tiles there. This is possible for both the current map view using the tools menu, and to open a specific waypoint marker after clicking it’s location field.
During precache rendering, you can still use the map, but the parts that will still be loading will be fuzzy for a while. Very large maps (larger than 20 mb, or more than 2000 sq. inches) are slower to render in this version (hey, it’s a mobile phone). For larger areas, I’ve been splitting the exported map into separate files. When multiple maps loaded in, there is a Maps table of contents listing.
I found a couple continuing quirks with the app and one major missing feature. The app really needs to export the map’s waypoints as CSV, KML, and GPX as an email attachment. I wish repositioning an existing pin was easier. The hit areas on some buttons is small, making it hard to use in a moving car. Sometimes it’s nice to have multiple marker icon labels open, but sometimes that is odd. At any rate, there’s no way to close them all en mass.
Quick and dirty test GeoPDF files:
(using Natural Earth, US Census, and other draft data)
Note: Because of USGS website quirks, it is not possible to directly download a USGS GeoPDF onto your iPhone/iPad in the field. The website doesn’t render properly (something about IE and cookies), and the resulting download file is ZIP format rather than PDF. Not sure why, since the PDF should already be optimized for file size (there’s only a 1.5% file size savings between ZIP and PDF in the Washington D.C. West quad sheet).
Check out more screenshots:
I presented the keynote last month at WhereCampPDX, a fun, free “unconference” in Portland, Oregon focusing on all things geospatial. Lots of discussions and met great people. The PDF of my presentation can be downloaded at kelso.it/x/pdx.
I talked about “cities and the people that live them” with particular focus on how do we count people, how grouping thematic and enumeration unit size changes with map scale and has specific impact on geofencing and choosing which cities to show at different web map zoom levels. The biggest hole in GeoNames.org and other gazetteers is the 3rd world, primarily in India and China but also Africa, also where most population growth will occur the next generation.
Here are some preview slides:
German dialects and migration: How linguistic variations affect where Germans choose to live (Economist)Friday, August 13th, 2010
[Editor's note: Sprechen Sie Deutsch? I keep returning to this article from the Economist from earlier this year in March. You might also enjoy: What's the point of counties? (UK) and The English apple season starts – though they're hard to find.]
Republished from the Economist.
FEW Germans now say Appel rather thanApfel (apple) or maken instead of machen(to make). The north German dialects that use such variants are mostly dead or dying. But the cultural differences that they reflect still govern behaviour today, says a paper from the Institute for the Study of Labour, in Bonn*.
Acting on imperial orders in the 1880s, a linguist called Georg Wenker asked pupils from 45,000 schools across the new Reich to translate standard German sentences into local dialect. The results were used to compile an atlas of linguistic diversity. The new paper shows that Wenker’s dialect regions still define the comfort zones in which Germans prefer to live. When people migrate within Germany, they tend to go to places where dialects resemble those spoken in their home region 120 years ago.
German dialects, formed by geography and political and religious fragmentation, express deep-seated cultural differences. These persist even though borders between petty princedoms are invisible (and often no longer audible). Even small differences count. Swabians share Baden-Württemberg with Badeners. Both spoke Alemannic dialects. But Swabians, who say Haus (house), have a bias against living in the neighbouring old grand duchy, where they say Huus.
That trade is livelier among regions that share a language is well known. The paper’s authors think they are the first to find a similar effect within a single language in one country. They measure migration not trade, because the data are better and cultural factors matter more. The best predictors are still Wenker’s maps. “Even when we don’t speak dialect, the cultural territory is still there,” says Alfred Lameli, one of the authors.
Does this confuse cause and effect? Regions may have similar dialects because earlier generations migrated and their descendants follow suit. To rule this out, the authors looked at the way communist East Germany weakened social links that encourage migration. After unification, they found, the old migration patterns came back, suggesting that migrants respond to cultural factors more than to social ties. It seems that neither television, nor the autobahn, nor even the Kaiser, has created a single country in Germany.
*“Dialects, Cultural Identity, and Economic Exchange” by Oliver Falck, Stephan Heblich, Alfred Lameli and Jens Südekum, IZA, February 2010
[Editor's note: Humorous take on surveying and ground truthing from the neogeography perspective in Africa. Topics include season planning, mental maps, asking for local knowledge, keeping a trip diary, and sharing results back with the surveyed community.]
Republished from Mapping: No Big Deal.
Mapping hardly accessible, rural areas, is always a challenge. Each area differs so you have to tackle it in its own special way. Yet some basic steps are always the same. I have written some of them down.
In July, Mildred and I went mapping on Mount Elgon as contractors for the National Democratic Institute (NDI) on behalf of Map Kibera. They needed information regarding polling stations in the area for their work on election monitoring. The information included geographic location, accessibility – both physical accessibility and the availability of cell phone service, information related to infrastructure of these stations, and speed of travel to each individual station.
Here is how we tackled the problems step by step:
1. Season planning.
The first and most important step in planning the mapping project is season planning. Obviously you want your work to run smoothly, without too many interruptions which is most of the time not the case. Season planning saves time, energy, money and nerves, takes the nature out of the equation, and lets you focus on other – project related problems.
While mapping on Mount Elgon we overlooked this very crucial step because the results were urgently needed. In an ignorant human and naïve researchers manner we thought we could conquer nature or at least go over every obstacle it put on our way. We should have known better. June and July being the peak of winter, it was cold and raining all the time. We only had a window of six hours per day when we could work, and the other eight hours we tried to save ourselves from the mountain. Because of the rain, roads became impassable and everything came to a standstill. I can comfortably say we lost at least two to three days of mapping because of the rain and as a result we lost money.
Exploring Place through User-generated Content: Using Flickr to Describe City Cores (Spatial Info Sci)Monday, August 9th, 2010
[Editor's note: Good focus on vernacular geography, on how we name and describe space, with a particular focus on downtown city cores explored thru millions of photos on Flickr. "Importantly, it deals with regions which are typically not represented in formal administrative gazetteers and which are often considered to be vague." Never seen Flickr geography before? Check out Aaron's flickr shapetiles (map), shpfile browser, and geotagger world atlas.]
Republished from the Journal of Spatial Information Science.
By Livia Hollenstein and Ross Purves
Terms used to describe city centers, such as Downtown, are key concepts in everyday or vernacular language. Here, we explore such language by harvesting georeferenced and tagged metadata associated with 8 million Flickr images and thus consider how large numbers of people name city core areas. The nature of errors and imprecision in tagging and georeferencing are quantified, and automatically generated precision measures appear to mirror errors in the positioning of images. Users seek to ascribe appropriate semantics to images, though bulk-uploading and bulk-tagging may introduce bias. Between 0.5–2% of tags associated with georeferenced images analyzed describe city core areas generically, while 70% of all georeferenced images analyzed include specific place name tags, with place names at the granularity of city names being by far the most common. Using Flickr metadata, it is possible not only to describe the use of the term Downtown across the USA, but also to explore the borders of city center neighborhoods at the level of individual cities, whilst accounting for bias by the use of tag profiles.
[Editor's note: Completed this June, the Atlas of Historical County Boundaries compiles the day-by-day change in county-level administrative boundaries in the United States from 1776 to 2010. Files are available in high-resolution GIS shapefiles and KML with full metadata on legal descriptions, online preview available. Thanks Andy!]
Republished from the Newberry Library.
A project of the William M. Scholl Center for American History and Culture at The Newberry Library in Chicago, the Atlas of Historical County Boundaries is a powerful historical research and reference tool in electronic form. The Atlas presents in maps and text complete data about the creation and all subsequent changes (dated to the day) in the size, shape, and location of every county in the fifty United States and the District of Columbia. It also includes non-county areas, unsuccessful authorizations for new counties, changes in county names and organization, and the temporary attachments of non-county areas and unorganized counties to fully functioning counties. The principal sources for these data are the most authoritative available: the session laws of the colonies, territories, and states that created and changed the counties.
What makes this Atlas stand out?
Over a dozen features distinguish the volumes and files of this atlas from other compilations.
- All boundary changes in states and counties-unrivaled historical and geographic coverage.
- Non-county areas-never before compiled or mapped.
- Attachments to operational counties (non-county areas and unorganized counties)-never before compiled or mapped.
- Separate map or polygon for every different county configuration-clarity and ease of use.
- Based on original research in primary sources-unlike most reference works.
- Primary sources cited for every change-unmatched documentation.
- Information organized by both date and county-unmatched flexibility.
- Locator maps for all county maps-show each county’s location within its state.
- Area (sq. mi.) for each county configuration-available nowhere else.
- Polygons available in two formats: shapefiles and KMZ-broad applicability.
- Interactive map has many options for background-unmatched convenience.
- Supplementary bibliography, chronologies, and commentary-unusually complete and thorough data presentation.
- Short and Long metadata documents for each state dataset-convenience and completeness.
The Newberry Library makes these data available without charge over the Internet in two digital formats: as shapefiles that users can download for use with geographic information system (GIS) software and as interactive maps, derived from the shapefiles, that users can view and manipulate (e.g., pan, zoom, add or subtract modern boundaries) at the Newberry’s Website