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Urbanization alters the thermal and dynamic environment of the local climate system, resulting in significant impacts on precipitation in both urban and adjacent areas. Nevertheless, there remains a significant gap in our understanding of urbanization‐induced effects on asymmetrical, symmetrical, and other precipitation patterns in urban agglomerations (UAs) with divergent background climates and geographic regions at different timescales. Specifically, this asymmetrical change pattern is characterized by an increase in heavy (or light) rainfall and a decrease in light (or heavy) rainfall. Here, we assessed the effects of urbanization on precipitation patterns across 18 UAs situated in diverse background climates and geographical areas in China at different timescales. The results demonstrate that urbanization predominantly alters precipitation patterns in UAs located in the humid region. Specifically, urbanization amplified asymmetrical changes in Yangtze River Delta, Pearl River Delta, Beibu Gulf, Middle Yangtze River, and Guanzhong, but exacerbated symmetrical changes in precipitation in some regions such as Chengdu‐Chongqing. Notably, the urbanization effect demonstrates greater significance at the hourly scale, as exemplified in the Yangtze River Delta, Pearl River Delta, and Middle Yangtze River, where the urban impact is nearly twice as pronounced when compared to the daily scale. Moreover, urbanization had either no effect or has a negative impact on precipitation patterns in UAs located within continental and arid regions. This is related to the intensity of urbanization, background climate and complex topography. This finding implies that urban managers should consider the impact of urbanization on precipitation patterns in different contexts to provide scientific guidance for urban planning. Plain Language Summary: China has undergone rapid urbanization in recent decades, resulting in increased heavy precipitation and decreased light precipitation in specific urban agglomerations. However, the influence of urbanization on different precipitation patterns (e.g., symmetric and asymmetric) at various timescales remains uncertain. This study investigates rainfall pattern changes across 18 urban agglomerations with diverse geographical locations and background climates. Our findings reveal that from 1961 to 2015, urbanization primarily modified precipitation patterns in humid regions, amplifying asymmetric changes in the Yangtze River Delta, Pearl River Delta, Middle Yangtze River, and Beibu Gulf. Importantly, in specific urban agglomerations, the impact of urbanization on precipitation is more pronounced at the hourly scale compared to the daily scale. Key Points: The influence of urbanization on precipitation change patterns at various time scales were investigated in 18 Urban Agglomerations in ChinaUrbanization has altered the precipitation patterns in the humid zone, amplifying heavy rainfall and suppressing light rainfall in the Yangtze River Delta, Pearl River Delta, Beibu Gulf regionsThe precipitation effect of urbanization exhibits a more pronounced variation on an hourly scale, being twice as substantial as on a daily scale in specific urban agglomerations [ABSTRACT FROM AUTHOR]

Urban functional zones are important space carriers for urban economic and social function. The accurate and rapid identification of urban functional zones is of great significance to urban planning and resource allocation. However, the factors considered in the existing functional zone identification methods are not comprehensive enough, and the recognition of functional zones stops at their categories. This paper proposes a framework that combines multisource heterogeneous data to identify the categories of functional zones and draw the portraits of functional zones. The framework comprehensively describes the features of functional zones from four aspects: building-level metrics, landscape metrics, semantic metrics, and human activity metrics, and uses a combination of ensemble learning and active learning to balance the identification accuracy of functional zones and the labeling cost during large-scale generalization. Furthermore, sentiment analysis, word cloud analysis, and land cover proportion maps are added to the portraits of typical functional zones to make the image of functional zones vivid. The experiment carried out within the Fifth Ring Road, Haidian District, Beijing, shows that the overall accuracy of the method reached 82.37% and the portraits of the four typical functional zones are clear. The method in this paper has good repeatability and generalization, which is helpful to carry out quantitative and objective research on urban functional zones. [ABSTRACT FROM AUTHOR]