Simulated satellite imagery at sub-kilometre resolution by the Hong Kong Observatory

Abstract

Simulated satellite imagery offers a direct means for visual evaluation of high-resolution numerical weather prediction (NWP) output, giving potential insights into a model's ability to represent weather systems at various spatial scales. This study explores the feasibility and performance of an experimental, large-domain 200m-resolution configuration of the Hong Kong Observatory's sub-kilometre Aviation Model (AVM) in reproducing cloud features over the geographically complex Pearl River Estuary, as observed by visible and infrared channels of the Advanced Himawari Imager of the Himawari-8 satellite. Simulated radiances using the RTTOV radiative transfer model are able to provide realistic predictions of observed cloud occurrence spatial distribution, even under complex atmospheric conditions involving multiple cloud regimes, highlighting the potential scientific and operational values of photo-realistic satellite imagery products based on very high-resolution NWP.