Alert and warning frameworks in the context of early warning systems

The 12th UNU-EHS InterSections, by Juan Carlos Villagrán de León, Ines Pruessner and Harold Breedlove, presents a comparative review of early warning systems established by Member States around the world for a variety of hazards from the perspective of their alert and warning frameworks. The authors urge us to recognize existing differences among these systems which arise as a consequence of the need to adapt such systems to the dynamics of environmental events. These differences are manifested in the number of danger and risk levels which are employed within different systems, the criteria used to define such levels as well as the nomenclature employed to differentiate the levels.