Variation in the spatial organisation of daily rainfall during the north Queensland wet seasons, 1979?82

Abstract

Daily rainfall correlation fields are examined for the north Queensland wet season months (November-March) for four consecutive years. Considerable monthly variation in correlation patterns is exhibited which is shown to be closely associated with the nature of the prevailing atmospheric circulation. Daily rainfall patterns are characteristically sporadic during the early part of the wet season (November and December), but later, and during January in particular, rainfall is more widespread and better organised. In February and March the degree of organisation decreases markedly as rainfall activity along the monsoon trough moves progressively northwards. During the period January to March and for days on which the monsoon trough is particularly active, there is a tendency for rainfall to be preferentially organised along marked axes. Axial eccentricity in correlation fields is related to orientation of the monsoon through when it is in the north of the region, and is also influenced by the trend of the east coast and adjacent high ground.