Quantifying light pollution

- We review new available indicators useful to quantify and monitor light pollution.
- These indicators are a primary step in light pollution quantification.
- These indicators allow to improve light pollution mapping from a 2D to a 3D grid.
- These indicators allow carrying out a tomography of light pollution.
- We show an application of this technique to an Italian region.

In this paper we review new available indicators useful to quantify and monitor light pollution, defined as the alteration of the natural quantity of light in the night environment due to introduction of manmade light. With the introduction of recent radiative transfer methods for the computation of light pollution propagation, several new indicators become available. These indicators represent a primary step in light pollution quantification, beyond the bare evaluation of the night sky brightness, which is an observational effect integrated along the line of sight and thus lacking the three-dimensional information.