Strictly Spatial #9

24 February 2016

Strictly Spatial 9a


Five years ago, at 12:51pm on the 22nd of February, Christchurch was rocked by a deadly 6.3 magnitude earthquake. As you all know this devastated Christchurch. Five years on, we are rebuilding and re-envisioning our city. In this edition of Strictly Spatial we look at how GIS has been used worldwide to assist emergency efforts in quake ravaged communities.

On the 25th April, 2015 a 7.8 magnitude earthquake struck the Himalayas, greatly effecting Nepal. Nepal had limited geospatial information, coupling that with the effects of a disaster, it made accessing remote communities incredibly difficult; until crowdsourcing joined in. For those of you who are unfamiliar with the concept of crowdsourcing, here is an informative article on the idea.

In Nepal, crowdsourcing was used in numerous ways, comparing pre/post imagery to find damaged buildings, mapping out previously unmapped roads, (using the imagery) giving those roads an accessibility rating, and mapping out help requests, shelters, aid distribution centres and more. Two very interesting blogs on crowdsourcing during the Nepal relief efforts can be found here and here

More complex GIS analysis was also used to assist Nepal post disaster. This article from the Penn State University Department of Geography explores some of these. For a map centric, informative view of the disasters, take a look at Esri’s Nepal Earthquake Maps. These informative maps help to understand the scale of the devastation in the country.

Strictly Spatial 9b2Shortly after the Christchurch earthquake, Japan was effected by an 8.8 magnitude earthquake and a subsequent tsunami. Again, crowdsourcing played a vital role in helping the relief efforts. Combine this with existing datasets, resulted in a swath of GIS data. Just some of this data can be found here. Maps and other spatial resources were developed and released – all of which assisted with relief efforts. An interesting article published by Joseph Kerski takes a geospatial perspective and looks at the events in Japan and how spatial and GIS helped the rescue and relief efforts.

  Many of you would have been involved at some point during the past five year in work to rebuild Christchurch. Many companies are leveraging GIS tools to convey information to the public and to keep track of work. There are some interesting online maps on the CERA website, they can be found here.

To assist in the immediate recovery, high resolution (0.1m) imagery was taken of Christchurch two days after the February quake. This imagery is now available for public viewing and use. You can download this off the LINZ Data Service portal. There is also a 2m resolution DEM available from Canterbury Maps.

Strictly Spatial 9c

That’s this edition of Strictly Spatial done. As always, if you have any interesting spatial stories to share with us, let us know through Twitter, Facebook or Email.

Kia Kaha Christchurch


ChristChurch Cathedral Image taken from Cathnews: