The Major Role of Anthropogenic Emission Underestimation in PM2.5 Estimation Uncertainty Over the Tibetan Plateau

Abstract

In recent decades, the Tibetan Plateau (TP) has experienced a notable rise in fine particulate matter (PM_2.5) levels, impacting its climate and ecology. However, accurately simulating PM_2.5 concentrations on the TP remains challenging. This study investigates the uncertainties in PM_2.5 underestimation, including meteorological conditions, dust emissions, regional transport, and emission inventories. Results show that discrepancies in various anthropogenic emission inventories significantly hinder accurate PM_2.5 concentration reproduction on the TP, overwhelming meteorological predictions, dust emissions, and regional transport contributions. With meteorological simulations showing similar discrepancies to those in other regions, limited improvement from increased dust, and a relatively high proportion of regional transport, it becomes evident that local emissions are underestimated. Modeling with adjusted anthropogenic emissions reveals a seasonal underestimation of 82.6%–92.6% of local anthropogenic emissions on the TP. This research emphasizes the need for an accurate anthropogenic emission inventory in understanding climate change on the TP.