Reassessment of ground-water recharge and simulated ground-water availability for the Hawi area of North Kohala, Hawaii

Estimated groundwater recharge for mid-century and end-of-century climate projections, Kaua‘i, O‘ahu, Moloka‘i, Lāna‘i, Maui, and the Island of Hawai‘i

“…The water-budget model generated daily rainfall data for the 1978-2007 scenario by disaggregating the monthly values of the 1978-2007 rainfall distribution maps using the method of fragments (for example, Oki, 2002). High-resolution, 250-m grid size maps of daily rainfall during 1990-2014 for the Hawaiian Islands, developed by Longman and others (2019), were used to disaggregate monthly rainfall into daily rainfall fragments for the water-budget model.…”

Effects of drought and cloud-water interception on groundwater recharge and wildfire hazard for recent and future climate conditions, Kauaʻi, Oʻahu, Molokaʻi, Maui, and the Island of Hawaiʻi

“…WATRMod generated daily rainfall for the simulations by disaggregating the monthly values of the 1990-2012 rainfall distribution maps using the method of fragments (for example, Oki, 2002). High-resolution maps of daily rainfall during 1990-2014 for the Hawaiian Islands were developed by Longman and others (2019) at a grid size of roughly 250 m. The rainfall maps from Frazier and others (2016) and Longman and others (2019) both use the same grid to quantify the spatial distribution of rainfall across the five islands.…”

Water-budget accounting for tropical regions model (WATRMod) documentation

“…Model users, however, can specify daily values for rainfall, fog interception, runoff, ET o , and supply-based irrigation by preparing additional input files that contain observed or estimated, sequentially ordered ratios of daily-to-monthly values. The daily pattern for rainfall also can be determined using the method of fragments (see, for example, Oki, 2002), which assigns daily rainfall values according to observed or estimated ratios of daily-to-monthly rainfall through a random selection of sets of daily-to-monthly rainfall ratios. The code also accommodates simple relations (uniform, linear, or exponential) between rainfall and selected water-budget components.…”

“…WATRMod can compute daily rainfall values from monthly rainfall values in one of two ways: (1) by randomly selecting user-defined monthly sets of daily-to-monthly rainfall ratios that are based on historical data or other information for each month of the year using the method of fragments (see, for example, Oki, 2002); or (2) by using an ordered sequence of daily-to-monthly rainfall ratios defined for each month of simulation. For a particular month, the daily rainfall is determined by multiplying each daily-to-monthly rainfall ratio for that month by the monthly rainfall.…”