{"id":1057,"date":"2015-05-26T23:30:01","date_gmt":"2015-05-26T23:30:01","guid":{"rendered":"http:\/\/blogs.lincoln.ac.nz\/gis\/?p=1057"},"modified":"2023-05-07T04:10:19","modified_gmt":"2023-05-07T04:10:19","slug":"opening-up-open-street-map","status":"publish","type":"post","link":"https:\/\/blogs.lincoln.ac.nz\/gis\/opening-up-open-street-map\/","title":{"rendered":"Opening Up Open Street Map"},"content":{"rendered":"

This post gives some background on Open Street Map, an open source, crowd sourced alternative to Google Maps. \u00a0We also cover how data can be downloaded and used for analysis.<\/em><\/p>\n

A key aspect of our\u00a0postgrad GIS courses is an independent project, where students formulate their own projects to ensure they develop some analysis skills in an area that’s important to them. \u00a0As the majority of students in the courses are from off-shore, and are interested in doing some analysis in their home countries (or elsewhere), we’re often in the difficult position of having to get data from and for other places – something that can be quite a challenge, particularly in countries where the spatial data infrastructure (i.e. availability of data) is not well developed. \u00a0We’re pretty well served here with data on the J: drive<\/a>\u00a0and on-line portals<\/a> (Koordinates.com<\/a>, the LINZ Data Service<\/a> and the Landcare Data Portal<\/a> (LRIS) but the rest of the world can be patchy.<\/p>\n

Case in point, Krishna Gurung, with us from Nepal, who was keen to get his hands on some useful data, including walking tracks, roads, and elevation in particular. \u00a0While I was initially very doubtful of getting our hands on some data, I’ve been pleasantly surprised by what we’ve been able to get.<\/p>\n

Data for his project was acquired from two main sources: Open Street Map<\/a> and the United States Geological Survey (USGS). \u00a0In this post I’ll mainly focus on the former, but a future post will look in more detail about how remotely sensed data can be downloaded from the USGS.<\/p>\n

To start off, let’s look at\u00a0Open Street Map<\/a>. \u00a0Here’s a local example of what you might see:<\/p>\n

\"OSMCanterbury\"<\/a><\/p>\n

Open Street Map is essentially an open source alternative to Google Maps, but instead of being developed and maintained by the minions at the Googleplex, everything you see on Open Street Map (henceforth, OSM) has been crowd sourced, i.e. anyone interested in contributing can. \u00a0Anyone. \u00a0So all that you see was created by people interested enough to put the effort in. \u00a0OSM was inspired by Wikipedia in that everyone’s an editor. \u00a0There are some rudimentary query features so you can see attributes in a GISy sort of way – click on the “?” at the right border and then click on a feature on the map and you’ll see what amounts to an attribute table at left.<\/p>\n

Features can be digitised in or GPS tracks can be uploaded which are then checked by someone further up the food chain before being approved and added to the global database. \u00a0As you can see above, there’s a lot of potentially useful data for some basic analysis. \u00a0A real plus of OSM is if you can see the data you can download it with the right tools. \u00a0 There are a variety of tools available, and a lot of variation in the degree of difficulty, but the good people at ESRI have developed an editor that can be built in to ArcGIS. (Note the “Export” button – this is a quick way to get a hold of the data but there are several, challenging data hoops to jump through before getting to work with them easily – not for the faint of heart.)<\/p>\n

The ArcGIS Editor for OSM<\/a>\u00a0toolbox can be downloaded and then installed on your machine. \u00a0Installation is pretty straightforward (check with ITS if you want to do this on an LU machine):<\/p>\n