Posts Tagged ‘haiti’

Preview of Natural Earth version 1.2 populated places

Tuesday, May 4th, 2010

Version 1.1 brought Natural Earth up to ~7,000 populated places (purple hollow circle icons with labels). Version 1.2 will increase that by 25 times to about 175,000 populated places. It will be available as a supplement to the 1.1 version selection. What does this get you? A 1:1 million scale map of cities around the world and a 1:250,000 scale map of the United States and other select countries. There’s still basic selection work to be accomplished (Santiago Chile has duplicate points now, as does London) and scale ranks need refining (boosting blue 10 million, 5 million and 2 million selections from the 1:1 million black dots on these preview maps).

Because the world’s geo infrastructure sucks, not all the new features will have population counts in the 1.2 version. But most should have areal extent bounds and nesting to indicate if the town is part of a larger metro area. At the 1:250,000 scale (gmaps zoom 11), we start to see actual incorporated towns and unincorporated suburbs, but at the 1:1m scale we’re still dealing primarily in metropolitan and micropolitan features (urban areas that host multiple “cities”).

The names of the feature will also need work, but that will occur after the 1.2 release (India, China, and Central Asia mostly). The version 1.1 locations will be shifted over to use the more accurate geoNames lngLats for about 6,000 features (note Oakland below). Locations were fine at 1:10,000,000 scale but don’t always hold up on zoom in. A later update will incorporate an additional 100,000 places to flesh out the 1:1m scale and maybe a few extra for closer in. Combine these populated places with roads and they start looking like atlas plates :)

More preview images after the jump.

sfbayarea

haiti

iraq

More preview maps after the jump.

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Haiti OpenStreetMaps + Google Map Maker

Thursday, January 21st, 2010

There are two camps opening up in the Volunteered Geographic Information (VGI or community generated content CGC) community that are sure to have big import going down the line. One is OpenStreetMap.org (editor | download) and the second is Google’s Map Maker (not available in the US and other developed world locations) (editor | tile view options | download). Both services allow users to either upload their own GPS track or digitize linework and points off satellite imagery. These two options have added to the global map, often creating the first detailed map of a place ever available to the general public.

But the two projects have very different license structures (OSM almost unrestricted, Google very restricted). Not only do they duplicate effort, but they result in “similar but different” products that do not perfectly register with each other. This is an problem that faced many in the US in the 1990s as many organizations developed their own, not-interoperable datasets for the same regions. That model has largely been replaced by single entities building fundamental datasets that other organizations and individuals repurpose.

The licensing and data coverage & registration issues are of note to professional cartographers (and first responders) more so then to the general public. But, as Sean says:

OSM and MapMaker aren’t talking and I think it is a big problem – if you want to help rescue efforts in Haiti where do you go to digitize? OSM? MapMaker?

Muki Haklay has a good comparison of the detail in each of OSM and Map Maker for Haiti. In the map here, yellow means that there is a better coverage in Map Maker, and blue means that there is a better coverage in OpenStreetMap.
Screenshot below, click for larger version.

osm-mapmaker-haiti-180110

“The comparison looks at total roads length for both datasets. The calculated difference between them using the equation:

∑(OSM roads length)-∑(Map Maker roads length)

for each 1km grid square.

The information in the file can be used for the following applications:

  • Users of these mapping products - it can help in judging which dataset to use for each area.
  • Users – it can facilitate conflation -  the process of merging datasets to create a better quality output.
  • Mappers - it can illuminate which areas to focus on, to improve coverage.”

Haitian Earthquake Emphasizes Danger of a Split Geo Community (seen over at FortiusOne’s Off the Map blog advocating for Creative Commons 0 “zero” licensing of geodata during disasters) has a overlay of OSM (Open Street Map) and Google Map Maker data.

4276602759_bbf15d1d1f

And finally, before and after images of OpenStreetMap.org map for Port-au-Prince, Haiti:

OSM just after the Earthquake

before4274264767_c9933d12c5

OSM Today

after4274264771_6873e16fa0