Due to its high population and rapid economic growth, Beijing ranks among the most polluted cities worldwide. Besides the rising demand for reliable anthropogenic emission estimates, the evaluation of emissions from the biosphere and their effects on air pollution is very important for addressing environmental issues such as air quality degradation and climate warming. The aim of the IBBAC project was to evaluate the impacts of biogenic VOC emissions on air pollution levels in Beijing and surrounding areas. Among the biogenic VOCs, isoprene is the most largely emitted and is therefore a primary focus of this work.