Linear scales usually don't have an intuitive upper limit that people can understand ("is 10000 bad?").
Citizen-facing scales should optimally go from 0 (no concern) to 10 (either world-shattering event or highest value ever observed). Due to the nature of how many natural disasters scale in impact on humans, this will often result in an logarithmic scale.
As an enthusiastic amateur photographer I'm a big fan of log_2 scales. Photography is full of them, most settings follow it and photographers call them "stops". One stop more is twice the light. People don't even think about logarithmic scales but it's very easy to intuit what going up and down the log_2 scales will result in.
Citizen-facing scales should optimally go from 0 (no concern) to 10 (either world-shattering event or highest value ever observed). Due to the nature of how many natural disasters scale in impact on humans, this will often result in an logarithmic scale.