The Influences of Inversion Height on Precipitation and Airflow over the Island of Hawaii

Publisher Website
Google Scholar
Abstract
Both the daily rainfall on the windward side of the island of Hawaii and the early morning (0200 HST—Hawaiian standard time) trade-wind inversion height at Hilo varied substantially during the Hawaiian Rainband Project (HaRP). In general, the inversion was higher during the passage of a cold front to the north or during the approach of tropical disturbances from the east to the south. The daily rainfall on the windward side is highly correlated with the 0200 HST inversion height at Hilo with a maximum correlation greater than 0.7 in the Hilo area. The daily daytime (1100–1900 HST) rainfall on the windward slopes, nocturnal (1900–0300 RST) showers an the windward lowland, and coastal precipitation in the predawn and early morning hours (0300–1100 HST) are also highly correlated with the inversion height with a maximum correlation greater than 0.7, 0.7, and 0.5, respectively. For the low- (high-) inversion days, the median daily rainfall on the windward side is about one-half (more than twice) of the HaRP median daily rainfall. On the high-inversion days, the afternoon clouds around the island wore closer to the summits of Mauna Loa and Mauna Kea than the low-inversion days because the upslope flow can bring the moist air from low levels to high elevations. The differences in the mean daily resultant winds between the low- and the high-inversion days are characterized by a weak northerly wind component on the windward lowland and an easterly wind component over the northern part of the island and at the southern tip of the island. It appears that slightly more air is forced to move around the island when the inversion is lower. For both the high- and low-inversion days, the surface airflow on the windward side is dominated by the daytime upslope flow and the nighttime downslope flow. For the ten high-inversion days, the modifications of the surface airflow by the effects of precipitation on the windward side are more significant than the ten low-inversion days because the rainfall amount is usually larger when the inversion is higher.

This publication has 0 references indexed in Scilit: