Geographic Data Sources
From Tactical Tech - Mapping for Advocacy WIki and Quick&Easy Guide
What kind of data do you want to map? And where does that data come from? These are two major questions that any organisation looking to integrate mapping technologies must ask. Geographic data comes from many sources and knowing where to find it or how to create it, can be a barrier that precludes organisations from taking advantage of the power of geographic information display. The categories below look at the different types of map data and should allow you to forge a better understanding of how to get started.
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Online Base Map Data
Have you ever pulled up a web browser and looked at a Yahoo! map? Have you ever explored the Google Earth programme? It is likely that a lot of the readers of this tool kit have. When we talk about online base map data, that is the kind of data we are talking about: data that is made available by such services as Yahoo! or Google Maps or programmes like Google Earth or NASA World Wind. This data is essentially freely available for the world to explore.
What can it be used for?
The types of data such services and programmes make available are primarily satellite imagery, national boundaries and road network data. This type of mapped information can be invaluable to many types of mapping projects. It can be used in simple ways - as a medium for posting photos associated with a geographic location - or in more complex ways - for identifying features in a satellite image or looking at a road network in a country.
Note: Not all data is created equal! While the U.S. and much of Europe benefit from having well-developed road network data available through services like Google Maps, that is not the case everywhere. Popular service providers are building their data holdings at an impressive rate and do make new, international data available regularly. But knowing exactly when your country might get updated high-resolution satellite imagery or a better-mapped road network just isn’t possible. The best thing to do is to check out a service to see what data is available in your area.
Perhaps you have data needs that go beyond what is provided by these services and programmes. Maybe provincial boundaries are an important feature to you. Or perhaps you require a dataset of hospitals and medical clinics in a region. You will probably have to look elsewhere. But whatever the case, exploring your area of interest in one of the major map API services or in a virtual globe is likely to be your best starting point.
User-generated data
Recent years have ushered in a new age of user-generated or volunteered geographic information, where lots of maps are being created and shared over the Internet. People are logging in to user networks with mapping applications at their core and “tagging” the house where they live. Others are taking photos or videos and placing them on a map, linking them to the location where they were shot. Some others still use a handheld GPS unit and record the path of a vehicle or the location of a protest. There are so many ways geographic information can be volunteered and shared. And the technologies to do this are advancing and fusing.
Social Networking Sites and Multi-media Mapping Ventures
In the last few years, many social networking sites have started using maps to allow people to locate themselves, connect with other users in their same area, as well as share photos, videos and other media. This has proved to be an interesting new application of maps and people are finding that networking via maps is easy and practical. A few of the major sites of interest – and which may provide inspiration for your own networks – are presented below. Note that in the context of social networking sites, many security and privacy issues apply - please read Tactical Tech's review of those sites and related concerns at Quick 'n' Easy Guide to Online Advocacy :
Socialight is primarily a service for place-based social networking. The website has a map at its core where users can create “sticky notes” to attach information to a place of interest (e.g. coffee shop, park, etc.). Other users can then explore the map and access the information. The service also allows users to send an SMS of their location to return information or access the service via a mobile web browser.
Socialight uses a Google Map API at its core. This is an example of a social networking site that has taken advantage of map APIs, in this case from Google.
A guide on how to use Socialight >>here<<
Flickr and Picasa are tools for online digital photo management. As part of the Flickr service, users can mark the source location of their photos on a map, a process called “geo-tagging”. Other Flickr members or a pre-defined community of users can then view the photos on an online map. The process of “geo-tagging” is as simple as dragging and dropping. The service uses a Yahoo! Map API at its core, while Picasa uses Google Maps. There are also applications that can be run from a mobile phone that allow not only one click upload of photos to Flickr and other similar websites but also automatically geo-tag them. The most known example of such a software is Shozu. The same thing can be done with photos stored on your computer with a new so-called social web browser Flock
A virtual tour how to geotag your pictures on Flickr >>here<<
Platial is the self-described People’s Atlas. This is primarily a social networking site where users create thematic maps using a simple interface on the Platial site. The maps can then be explored by users all over the world. The site uses a Google Map API.
Questions and Answers on how to use Platial >>here<<
VlogMap is an online resource for the video blogging community. The website features a number of resources and tools for exploring video blogs, including maps where video blogs can be marked to the location where they were filmed and then shared with the VlogMap community. Videos are marked to their source location by manually locating the source with a Google Map API. The VlogMap data can also be exported and viewed on the Google Earth platform.
Questions and Answers on how to use VlogMap >>here<<
Thanks to a new default layer in Google Earth, it is now possible to add "geo-tagging" to any videos posted to YouTube. It can be easily found under the “Featured Content” or "Gallery" section. Once enabled, each video shows up as a little YouTube logo that can be clicked for more information, such as a video thumbnail preview, how many views it has, and a community rating. It’s not clear if Google shows every geo-tagged video submitted to the service. To add "geo-tagging" to any videos on YouTube, it is necessary to go to the “date and map options” settings of an uploaded clip. Similar functionality is available through the Google Maps web service, and many projects are using it successfully, among them are VideoMap or VirtualVideoMap
Short guide how to geo-tag a video on youtube >>here<<
Facebook is an example of a very popular social networking site. The open platform allows third parties to create applications to be used within the programme. An example is Travel Map which is linked with Travellers Point. Another application that all registered Facebook members can use is Friends GPS application that allows "geo-tagging" of their location (from a computer or mobile phone), as well as adding photographs to the map and searching for people according to their location. It uses Google Maps API.
Web Maps and Google Earth
Maps are everywhere on the web today. These maps are not just being created by experts or computer programmers. The technology has been shaped so that non-experts can also create maps.
A particular data format is becoming a key component in how maps are shared — Keyhole Markup Language (KML). Read more about KML in the Glossary. If the idea of “data formats” initially seems overwhelming, that’s OK! It’s easy to interact with KML using Google Maps and Google Earth. Using either of these services, you can create maps that can be shared with others. The interface for doing so is easy and intuitive. But what you’re really doing is creating KML. If you create a map on Google Maps, you can also view the map on Google Earth. This allows for easier transitions between the two related technologies.
GPS and Mobile Phone Technology
Using handheld devices – such as laptops, GPS units and mobile phones - to collect geographic data is another way for users to create and share geographic information. Handheld GPS units take advantage of the US-owned Geographic Positioning System or GPS satellites. These connect with GPS receivers to “position” them or give the GPS receiver an exact location on earth. But mobile phones and other devices can position themselves in other ways, using mobile networks and wi-fi signals to locate the position of the user. A combination of mobile network and satellite signals can also be used.
This presents the unique opportunity to collect data or other media (photos and videos) in the field and upload them to maps to be shared with the world.
Some fundamental questions remain though. Which phones allow me to take pictures that can be “geo-tagged”? How can I take advantage of the technologies? What is the network climate in my country? All deserve thorough answers, unfortunately we cannot answer everything here. But we can provide a few interesting examples and suggest some resources for further exploration.
ZoneTag Photos is a service that allows users to upload pictures taken from mobile phones directly onto the Flickr photo sharing website. The service only works on supported phones and through network providers that serve primarily US markets.
An article about how to use Zonetag >>here<<
Ipoki is a web and mobile device social networking service that allows users to share their location with a group of pre-defined Ipoki users or "friends". Ipoki can be used through a web browser or through supported mobile devices.
Other Resources
Open Street Map is a wiki style map that can be publicly edited by users around the globe. In this way, a network of users are developing their own street maps and avoiding reliance on government or other hard-to-access data. Check out you area on the globe to see if Open Street Map is in your area.
A guide on how to use openstreetmap >>here<<
Government Data
Often geographic datasets are owned by national governments, UN bodies and NGOs. The trend seems to be moving towards free and open distribution of data sets, but that is not always the case. One country or UN body might readily make their data available and accessible with an easy interface, and another might not!
A nation’s vital geographic information and the climate in which it is distributed is often referred to as its spatial data infrastructure. The type of geographic data typically owned by the state is road and other infrastructure network data, state-run facility data (e.g. schools and hospitals) and administrative boundary data. A list of spatial data infrastructure resources and links is provided by the Global Spatial Data Infrastructure Association (GSDI).
The Southern Africa Humanitarian Information Management Network Initiative (SAHIMS) of the UNOCHA disseminates thematic data (and administrative boundary data) through their web portal for selected countries in southern Africa. This is one example of a UN organisation making geographic data available.
The data disseminated by SAHIMS is in a particular file format with the file extension .SHP: this is a file type common among geographic software platforms including many open source GIS programs.
Since there is no one place for all your geographic data needs, a good place to start is your country’s own geographic data dissemination practices and any UN body or major NGO that may engage in work related to yours. The Geospatial Data Infrastructure Association is also a resource that can help to get you started with investigating your country’s practices.
