Research News

Study Provides Detailed Insights into Urban Heat Emissions in China

Mar 29, 2024

In a bid to understand urban thermal environments better, researchers from the Aerospace Information Research Institute (AIR) under the Chinese Academy of Sciences (CAS) have developed a comprehensive dataset on anthropogenic heat (AH) emissions in China. 

AH refers to the heat released into the atmosphere as a result of human activities. With urban areas experiencing rapid growth and increasing heat emissions, the need for accurate data on AH sources has become critical.

This study, published in Resources, Conservation & Recycling on Jan.20, provides detailed information on various sources of AH, including building, industrial, traffic, and metabolic heat, captured at yearly, monthly, and hourly intervals with a spatial resolution of 500 meters.

To ensure accuracy, the researchers corrected existing inventory methods based on official energy consumption data for China.

By considering factors like national building height, factory density, and road density, the team created a model that accurately captures the spatial characteristics of AH from multiple sources. They employed a stacking framework, integrating several machine-learning algorithms, to construct a robust AH estimation model.

The results revealed significant variations in AH composition and total emissions across different regions of China. High concentrations of AH are clustered in the Yangtze River Delta, Pearl River Delta, and Beijing-Tianjin-Hebei region, with significant spatial variations among different anthropogenic heat sources. 

While building heat exhibits distinct temporal variations correlated with climate and latitude, industrial and traffic heat remain relatively stable throughout the year. 

Moreover, the spatial and temporal characteristics of AH from various sources were more detailed and accurate than previous studies. The spatial distribution of industrial heat was irregularly dispersed within urban areas rather than concentrated in city centers. 

Even though there are some discrepancies, the dataset shows strong connections (p<0.001) with previous datasets on anthropogenic heat. The correlation coefficients are consistently above 0.7, indicating a robust relationship between the new data and existing information on human-generated heat.

To validate their findings, the researchers incorporated the AH dataset into short-term climate simulations for both winter and summer. While the inclusion of AH improved air temperature simulations in winter, uncertainties in climate modeling limited its validation for AH.

Despite these limitations, the new dataset offers valuable insights into urban heat emissions, supporting research in urban climate dynamics and facilitating sustainable development efforts.