Satellite observations of clouds and precipitation have a history stretching back over 40 years. The observations of clouds initially led to the inference of precipitation from cloud top features and subsequently more direct methods derived from passive microwave observations. More recently, the Tropical Rainfall Measuring Mission (TRMM) has provided unprecedented information from the first active microwave instrument specifically designed to measure rainfall, the precipitation radar (PR). This paper utilises data from the TRMM PR for the period December 1997 to November 2005 to investigate rainfall over Hawaii and the surrounding ocean. The PR instrument not only provides spatial information on rainfall, but also vertical profiles of precipitation. Data from the PR instrument is used to map rainfall at a spatial resolution of 5 km and, utilising the information from the vertical profiles, map the distribution of trade-wind and non-trade-wind precipitation. This paper provides quantitative estimates of rainfall over Hawaii and the surrounding ocean that generally match those of surface observations and models. It is found that the islands exert a significant influence on the distribution of the amount and occurrence of precipitation over this region. Copyright (c) 2006 Royal Meteorological Society.
- Hawaiian islands