ATLAS stands for Anomaly Terror Level Advisory System. Now in its thirty-third year, it is Isermno's color-coded early warning alert apparatus, instituted in the wake of 1989's so-called "Terror from the Sea." While there is no consensus as to whether this ostensibly preternatural incident actually happened, its occurrence (or non-occurrence) prompted the government to found the programme.
Each of ATLAS's five color levels indicates a progressively imminent degree of danger. From lowest to highest, they are: green, blue, yellow, orange, and red.
As of this reporting, ATLAS has been elevated from green to blue.
A summary of each of the color advisory levels is given below.
Green / Low: They sleep, for now...
Blue / Guarded: They stir...
Yellow / Elevated: They're coming...
Orange / High: They're here!
Red / Severe: Run for your lives!