Characterization and indexing of heavy rainstorms in <scp>H</scp>ong <scp>K</scp>ong

Abstract

ABSTRACT Heavy rain events or rainstorms of various scales often occur in H ong K ong from A pril to S eptember. In extremes cases, they lead to serious landslides and flash floods resulting in loss of life, and damage to property and infrastructure. With climate change, extreme rain events are projected to be more frequent and more intense in this region. A system to gauge and label the severity of rainstorms would be useful for identifying and communicating extreme conditions in warning and disaster prevention operations. In parallel, a better understanding of the characteristics of rainstorms would also be important for impact assessments and engineering design purposes. This paper formulates a practical framework to index the magnitude and severity of rainstorms in H ong K ong. An index termed as the S everity I ndex combining the magnitude of different rainstorm attributes is devised for quantifying the overall severity of rainstorms. This index is flexible to allow tuning for specific applications.