Reconstruction of RegCM4-simulated Surface-layer Meteorology over a Megacity Using the Vegetated Urban Canopy Model

Abstract:

A dynamic downscaling approach using a regional climate model (RCM) has been popularly used to simulate current and future climate in order to overcome drawbacks relevant to low spatial and temporal resolution of global climate models. Despite the higher resolution (~few tens km), it cannot explicitly represent urban areas and associated physical processes in RCMs. This study introduces a methodology that reconstructs the Regional Climate Model version 4 (RegCM4)-simulated meteorology over urban areas using the vegetated urban canopy model (VUCM) which has a capability to explicitly represent complex urban morphology and physical processes in a local scale. Used are the RegCM4 simulation over the coordinated regional climate downscaling experiment (CORDEX) domain for 20 years (1986–2005) with a grid spacing of 50 km. The methodology’s performance in simulating near surface temperature for an East Asian megacity (Seoul) was evaluated against surface meteorological observation data. We will present the reconstruction methodology and evaluation result, and discuss meteorological factors that affect the RCM climatic simulation for urban patches.