弱コリオリ力におけるハリケーン強度のアンサンブル予報実験

Abstract

The influence of the Coriolis force influence on the intensity of Hurricane PALIthat was generated at 4.4°N on 7 January 2016 was examined. Ensemble downscaleexperiments were conducted using the nonhydrostatic meso-scale numerical model, WRF, with horizontal resolution of 10 km from the initial states derived from 11ensemble members of NOAA's 2nd-generation global ensemble reforecast dataset.Sensitivity to the intensity is identified by augmenting the Coriolis parameter. Alldisturbances with different values of the Coriolis parameter develop to the intensity ofTropical cyclone (TC, 17 ms−1). By changing Coriolis force, the intensity and size ofhurricane changed especially at the mature stage, but the tracks were almost the sameduring forecast time. Our sensitivity experiments suggest that TCs with larger Coriolisforce increased in size, but it does not necessarily make TCs stronger. Moreover, it isfound that the spread of TC intensity varies with the Coriolis force.