Know what you’re looking at.
The landscape is a teaching model. Its sources—and its limits—should always be visible.
Observed
Measurements or direct observations from a named source.
Reconstructed
A past landscape inferred from scientific evidence.
Simulated
A simplified process, never a hazard forecast.
Illustrative
Procedural terrain and visual scale, not survey data.
Natural Earth
1:10 million mapped Java and Sumatra coastlines. Relief and the small volcanic islands remain explanatory reconstructions.
Badan Geologi
Latest discoverable Krakatau bulletin, with reported time, quoted alert level and original recommendations.
Smithsonian · Global Volcanism Program
Krakatau chronology, geological setting and eruption reports.
British Geological Survey
Research on the flank collapse and the Sunda Strait tsunami.
PVMBG · MAGMA Indonesia
Check the official authority for current activity and local restrictions.
Darwin Volcanic Ash Advisory Centre
Timestamped observed, estimated and forecast ash polygons, retrieved from the official 24-hour advisory feed.
Open-Meteo
Hourly model wind at the surface and five pressure levels; fetched on demand with a ten-minute cache.
International Volcanic Health Hazard Network
Evidence-based ash exposure and respiratory protection guidance.
Java and Sumatra coastlines use Natural Earth map data. The small volcanic islands and their relief are reconstructed for teaching. Island arrangement is approximate, relief is exaggerated, and no surveyed elevation model is used. Particle paths and waves illustrate mechanisms; they cannot estimate exposure, inundation, arrival times or evacuation zones.