Featured case study
Mapping Ardmore in the 1926 Census
April 22, 2026How I built a local-history GIS site for Ardmore using the newly released 1926 Census records, static data exports, townland mapping, and careful data cleaning.
GIS, Public Data, and
Place-based Research
I'm Dónal O'Tiarnaigh. I build spatial analysis projects, local-history tools, and public-data experiments that turn scattered records into clearer, more useful stories.
Flagship Work
Two projects that best show the direction of the portfolio
These are the clearest examples of how I approach GIS, public records, and purpose-built tools: start with a place, clean the data, and make the result easier to explore.
Practice Areas
What the work on this site tends to focus on
Local History and Place-based Research
Rebuilding historical records around one town, parish, or landscape so they can be searched, mapped, and understood in context.
Public Data and Monitoring Tools
Turning fragmented feeds, thresholds, and agency datasets into practical interfaces that help people see what is happening right now.
Spatial Analysis and Mapping Methods
Using GIS, remote sensing, and statistical mapping techniques to explain patterns in health, environment, population, and place.
Recent Writing
Project archive and supporting write-ups
The rest of the site mixes recent builds with earlier GIS coursework adapted for the web. Together they show both current direction and the methods underneath it.
Analysing Twitter/X Sentiment: An Approach to Understanding Social Media Data
April 22, 2025Using R programming and multiple lexicon approaches to analyse sentiment patterns in 15,000 Avengers Endgame tweets/X posts, with applications for geospatial opinion mapping.
Mapping Dublin's Air Quality: A GIS Analysis of Urban Pollution Patterns
March 10, 2025Using GIS and Empirical Bayesian Kriging to visualise and analyse air pollution distribution across Dublin from Google Street View car data.
Mapping Dublin's Population Change with R
February 15, 2025Exploring population distribution and change in Dublin from 2006 to 2016 using R for spatial visualisation.
GIS for Healthcare Access Analysis
January 29, 2025This project represents my first in-depth application of GIS analysis techniques, focusing on healthcare accessibility and spatial disparities across Ireland's electoral districts (EDs).
Hello World
January 25, 2025Welcome to the show: A quick intro to the blog and my hopes for it going forward
Background
GIS work shaped by software, analysis, and communication
I'm based in the south of Ireland and work across GIS, data tooling, and technical problem-solving. If you want more context on how I work, the About page fills in the longer version.