Exercise Track: Anticipatory Action Analysis for Cyclones in Madagascar#
This exercise track focuses on the preliminary assessment of a cyclone event in Madagascar. The goal is to create an analytical workflow as a QGIS model that estimates the exposed population, exposed infrastructure, and exposed agriculture land. Additionally, the accessibility of exposed regions can be assessed using pre-calculated isochrones. In this track, you will build an analytical workflow as a QGIS model and visualise the results using map templates and style files.
French version - Version française
The french version of this exercise track can be found here:
La version française de cet article se trouve ici:
Context
Madagascar is frequently exposed to intense tropical cyclones, which can lead to widespread damage, displacement, and loss of life. Anticipatory analysis is essential to reduce the impact of these extreme weather events. By using forecast data and geospatial tools to predict the likely areas of impact, humanitarian actors and local authorities can take early action, such as pre-positioning supplies and issuing warnings, to protect lives and livelihoods before disaster strikes. This proactive approach strengthens preparedness and response capacities, ultimately saving time, resources, and lives.
Aina, the GIS expert at the Malagasy Red Cross (CRM), is preparing for the upcoming cyclone season. She wants to improve her team’s ability to act quickly once a storm is forecasted by automating key analyses in QGIS. These include estimating exposed populations, identifying impacted services like health and education, and assessing whether health posts can be reached from key warehouses within a critical 10-hour window. The goal is to prepare an end-to-end analysis and visualization workflow that can support fast, data-driven anticipatory action before a cyclone makes landfall.
Exercise 1: Estimating the Exposed Population - Aina’s Manual Approach (Module 5)
importing datasets into QGIS
reprojecting layers
buffering vector layers
clipping raster layers
calculating zonal statistics
applying graduated classification to results
Exercise 2: Automation of Exposed Population Estimation – Aina’s Model (Module 7)
Using the model builder
reprojecting layers
buffering vector layers
clipping raster layers
calculating zonal statistics
applying graduated classification to results
Exercise 3: Identifying Affected Health Facilities and Schools – Aina Adds More Layers (Module 7)
extending the model
Counting points in polygon
using the field calculator
Exercise 4: Visualizing Cyclone Impact Results – Aina Styles Her Layers (Module 4)
using the styling panel
applying style files to layers
saving style files
Exercise 5: Quick Map Creation – Aina Uses Map Templates (Module 4)
using the print layout composer to create a map
using map templates
using attribtue tables in the print layout composer