GIS Blog | Page 6

The GIS Detective – Have LiDAR, Will Travel

In this post we’ll see how LiDAR data were used to help understand a tricky problem. So I’ve got a bit of an issue at my house – and here it is: We live out on the Lyttelton Harbour on steep loess soils, which are prone to tunnel gullies – sub-surface channels that develop in…

Python Scripting with the Field Calculator

This post details how you can use some Python scripting to do if/else statements in the Field Calculator. If the title of this post and the intro haven’t put you to sleep already, read on! Perhaps they’ve even piqued your interest! (There are support groups available for this condition.) I was recently contacted by a…

Fun with Cholera!

This post looks at how data can be symbolised in different ways to make for more effective communication using data from John Snow’s mapping of the cholera outbreak in Soho. Well there’s nothing fun about cholera, really. But there are some important lessons we’ve learned about spatial thinking from cholera, particularly with an outbreak in…

Cholera, Spatial Thinking and John Snow: Soho 1854

A particularly bad outbreak of cholera in Soho in 1854 led one man to identify contaminated water as the mode of transmission and apply one of the most famous instances of spatial thinking. At a time when the fledgling Canterbury colony was getting itself sorted out, the London of 1854 was a stinking, festering hell-hole. Growing from the tiny…

LiDAR Data – Thousands of Tiny Luminous Spheres

This post covers the basics of LiDAR data and how very high resolution DEMs can be derived from LiDAR data. With an appropriate nod to The Bats, we’ll cover LiDAR data, which, while sort of luminous but not spherical, are certainly tiny and numerous. Thousands is a HUGE underestimate. LiDAR is a form of remote…

Getting Consistent Symbology with Layer Files

This post covers how you can get consistent symbology across several layers using layer files. So the good people in ERST310/607 have been doing some fun analysis lately (though they may disagree), getting some high-resolution elevation models from LiDAR data (more to follow on that topic). Using three separate datasets, they’re creating DEMs for three…

Trekking the High Himalaya for Data

This post covers how a range of different remotely sense data sets can be acquired from around the world with a focus on Nepal In a recent post, we looked at how Open Street Map can be used to acquire some basic geospatial data for many parts of the world. When we left off, we…

Opening Up Open Street Map

This post gives some background on Open Street Map, an open source, crowd sourced alternative to Google Maps. We also cover how data can be downloaded and used for analysis. A key aspect of our postgrad GIS courses is an independent project, where students formulate their own projects to ensure they develop some analysis skills in…

GIS in Action – Crowd Sourced Mapping of Earthquake Impacts in Nepal

This post looks at how GIS is being used in a crowd sourcing way to respond to humanitarian needs around the world. Recent event in Nepal have been eerily familiar – many of will know what it’s like living in the shadow of aftershocks and the long road ahead. There are lots of ways we…

Home on the Range

In this post we’ll cover the ins and outs of creating home ranges for animals based on point locations. This was mainly written as a tutorial for Ecology students but by all means, feel free to have a go. In animal ecology there’s an important concept around home ranges for animals, which could be thought…