Agency: United States Geological Survey (USGS)
Name: Aviation Color Code
Note: this scheme was the basis of the now standard ICAO aviation VAL scheme.
The terrestrial VAL scheme can be found here.
Elements of VAL system
| Domain | Aviation |
| Volcano | All |
| Scheme range | 4-level scale |
| Lowest level | 1 |
| Highest level | 4 |
| Level name type | Color |
| Level for lack/loss of monitoring | Yes |
| Volcanic activity | Yes |
| Hazards possible | Yes |
| Locations affected | No |
| Potential impacts | No |
| Forecast language | Yes |
| Timing language | Yes |
| Actions to take | No |
| Agency actions | No |
| Link to evacuations | No |
| Reporting frequency per level | No |
| Link to monitoring thresholds | No |
| Step-up and step-down language | Yes |
VAL sources and links
The images below are static examples of VAL information pages and DO NOT represent current alert levels. While we strive to maintain the links below, they may not always work. For the current alert level, please consult the proper institutional authorities.
VAL Dashboard
VAL Map
Reports
VONAs
Volcano Pages
Social Media
VAL Dashboard and Map (Alaska only)
Related References
Gardner, C.A. and Guffanti, M.C. (2006). U.S. Geological Survey’s Alert Notification System for Volcanic Activity. US Geological Survey Fact Sheet 2006–3139, US Geological Survey, Reston, VA. https://doi.org/10.3133/fs20063139
Fearnley, C. J., McGuire, W. J., Davies, G., & Twigg, J. (2012). Standardisation of the USGS Volcano Alert Level System (VALS): analysis and ramifications. Bulletin of Volcanology, 74(9), 2023-2036. https://doi.org/10.1007/s00445-012-0645-6
Guffanti, M., & Miller, T. P. (2013). A volcanic activity alert-level system for aviation: review of its development and application in Alaska. Natural hazards, 69(3), 1519-1533. https://doi.org/10.1007/s11069-013-0761-4