Natural environmental hazards and disasters involve
comparatively rare high-intensity processes and extreme events caused by both
terrestrial and atmospheric processes. The study of natural hazards includes
the consideration of identification of specific events, finding of their
causative factors, assessment of their impacts on human and other biological
communities, prediction of such events and finding their remedial measures. Natural
hazards fall in two broad categories (1) planetary hazards and (2)
extra-planetary hazards or extra-terrestrial natural hazards.