The Spatial Pattern Strategy of Urban Ecological Patches Based on the Mesoscale WRF-UCM Model: Taking Wuhan City as an Example

Abstract

In the context of rapid urbanization, the reduction of urban ecological land area, space chaos, and fragmentation have led to a series of climate and environmental problems. This paper takes the ecological patches of the urban climate environment compensation space as the research object and establishes several urban canopy models of several cases based on geographic information data. Then, we input them into the mesoscale WRF-UCM model and simulate after loading the meteorological data to derive the meteorological indicators of each case, quantitatively analyze the meteorological conditions in the ecological patch boundaries with different surface attributes, and conduct research on the “quality-efficiency” correspondence of the physical characteristics of the ecological patches and the spillover effects of climate regulation. Studies have shown that the highest surface temperature difference between water patches and patches with other attributes $∆\text{Tsk}$ is up to 6.5°C in winter and 11.5°C in summer. The highest temperature difference at a somatosensory height of 2 meters $∆T2$ is up to 2.0°C in winter and 3.0°C in summer, which can improve the surrounding environment. Under light wind conditions, water patches will have a positive spillover effect within 5.5 km of the downwind direction. Based on the data, an optimization strategy for the spatial pattern of urban ecological patches is proposed: the best distribution of water patches that are beneficial to the climate adjustment of Wuhan in winter and summer is in the north or northeast of the city, followed by the south or southwest. The north and northeast of the city should keep the woodland patches and reduce the setting of vegetation/arable land and wetland patches. This research is an interdisciplinary study of urban spatial planning that adapts to climate change, to supplement the deficiencies of urban planning theory, and to provide guidance for the promotion of green and ecological city construction.