"Traffic light reporting" generally implies metrics that should make sense to anyone having normal color vision, and an appreciation of the conventional sequence of colors meaning stop, ready and go. Short of binary yes/no type metrics (such as certified compliance), metrics doesn't get much simpler than traffic-light reporting ... or does it? According to April's eBulletin from New Zealand's Ministry of Civil Defence & Emergency Management:
"The different meanings of the colours used for tsunami threat level maps in national warnings and those used for tsunami evacuation zone mapping (specifically red, orange and yellow) were identified as confusing in exercises and real events. For instance, in the threat level maps red indicated a ‘severe threat’ of 8m+ amplitude while yellow meant a ‘moderate threat’ of 3-5m. In the Tsunami Evacuation Zones Guideline the opposite applies, with the ‘red zone’ being evacuated for the lower level threat and the ‘yellow zone’ in the extreme (worst) case."
The piece went on to describe a new set of 6 color-coded tsunami threat levels and definitions, developed by the Tsunami Working Group. While there is a green level, red and yellow/orange/amber are now conspicuously absent. Perhaps they were too obvious for the bureaucrats.
While it's easy for me to poke fun at the governmental approach to disaster planning, the obvious fact remains that NZ sits in a geologically-hyperactive region. Metrics relating to those and other incidents, plus scientific data from the geologists and other experts in plate tectonics stream into the government's risk assessment, planning and budgeting, while video footage from the Christchurch quakes, plus the Indonesian and Japanese tsunamis, represents the most graphic metric of all. Without the government's efforts, it is unlikely that we citizens would be able to coordinate our efforts to prepare for the next Big One. Let's just hope they have their act together.