Volcanic Ash & Aviation Colour Code Map

Volcano observatories assign each monitored volcano an Aviation Colour Code — Green, Yellow, Orange or Red — that summarises the hazard to aircraft. Green means normal, non-eruptive background activity; Yellow signals elevated unrest above known background; Orange means heightened unrest with increased likelihood of eruption, or a minor eruption underway; Red means an eruption is imminent or ongoing with significant ash emission expected into the atmosphere. Because the code is raised during unrest — often before the first ash is detected — it is a leading signal for flight planning.

A VAAC (Volcanic Ash Advisory Centre) advisory is issued once ash is actually observed or forecast in the atmosphere, and describes where the ash cloud is and where it is expected to drift. The aviation colour code describes the state of the volcano itself and is typically raised earlier, during unrest. This map shows both: the observatory colour code as the volcano marker, and a separate flag when a current ash advisory is active.

Aviation colour codes are a state, not an event — a volcano keeps its last assigned code until the observatory changes it, and some frequently-active volcanoes are held at Green or Yellow between ash episodes. When the most recent VAAC advisory for a volcano is a stand-down ("activity has stopped"), we drop the active-advisory flag and fall back to the observatory colour code, so the map does not claim an eruption that has ended.

Aviation colour codes are read directly from the issuing observatories — USGS in the United States and Alaska, INGV in Italy, the Icelandic Met Office, PVMBG (MAGMA) in Indonesia, and KVERT in Kamchatka — plus the Smithsonian Global Volcanism Program, which also provides the 1,196-volcano Holocene registry shown as the faint coverage layer. Satellite thermal anomalies are detected from MODIS/VIIRS radiative power. Ash advisories come from the Volcanic Ash Advisory Centres.

For each active volcano the map lists the nearest scheduled-service airports by straight-line distance, so you can see at a glance which hubs sit closest to the activity. This is geographic proximity only — it is not an operational impact assessment. FlySafe's scoring API turns proximity, ash-advisory geometry, wind and volcano state into an airport-level exposure signal for operators and insurers.

The underlying feeds are collected continuously through the day — colour codes and satellite thermal on a short cycle, VAAC advisories as they are issued — and this public snapshot is regenerated and redeployed alongside them. The timestamp above the map shows when the current snapshot was built.