The Hawai‘i and US-Affiliated Pacific Islands region is experiencing rapid changes in climate that have significant consequences for local communities and ecosystems. Many islands contain extremely steep climate gradients and complex microclimates, and therefore need high-resolution climate data products. Given that the average spatial resolution of a general circulation model is too coarse to capture the fine-scale variations on these islands, downscaling techniques are required to translate global-scale information to local scales relevant for decision-making. However, this region is excluded from most national climate downscaling products, which typically focus on the contiguous US. As a result, the region has depended on a patchwork of independent studies that often produce inconsistent results.

This presentation outlines the state of climate downscaling in the Pacific Islands region: what has been done to date, existing gaps, and future recommendations. We emphasize several newly available statistically downscaled datasets for the State of Hawai‘i, and ongoing work to test new methods. Compared to Hawai‘i, fewer projections are available for other Pacific Islands including Guam and American Samoa, which inhibits climate adaptation planning. We provide several recommendations for improving the availability of regional climate projections and their accessibility to users.