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South Asian air pollutants exert substantial effect on the climate and environment change over the Tibetan Plateau (TP). This paper investigates the trans-boundary transport of PM 10 , PM 2.5 , and O 3 from South Asia to the TP via WRF-Chem sensitive analysis. It is found that PM 10 , PM 2.5 , and O 3 over South Asia are mainly sourced from anthropogenic sources. South Asian emissions contribute up to 54% of PM 10 (PM 2.5) in the TP in the pre-monsoon season. For O 3 , the highest contribution of 18.13% is in the monsoon season, while the lowest contribution of 8.67% is in the winter season. To evaluate the respective contributions of anthropogenic and biomass burning emissions in South Asia to PM 10 , PM 2.5 , and O 3 in the TP, anthropogenic and biomass burning emissions in South Asia are considered separately. The results show that the largest percentage contribution of PM 10 (PM 2.5) from South Asian anthropogenic emissions to PM 10 (PM 2.5) in the TP with value of 35.86% (37.77%) occurs in winter, while the lowest percentage contribution of 16.52% (16.77%) appears in the monsoon season. For O 3 , the largest contribution of 17.74% from South Asian anthropogenic emissions appears in the monsoon season, whereas the lowest contribution of 8.59% occurs in winter. Compared to the anthropogenic emissions, the biomass burning emissions in South Asia have a relative less contribution to PM 10 , PM 2.5 , and O 3 in the TP. The largest contribution of PM 10 (PM 2.5) from South Asian biomass burning emissions to PM 10 (PM 2.5) in the TP is 20.04% (18.37%) in the pre-monsoon season. Conversely, the lowest contribution of 0.58% (0.53) appears in the monsoon season. O 3 from South Asian biomass burning emissions contributes <1% to O 3 in the TP in each season, implying that the biomass burning emissions in South Asia have little effect on O 3 in the TP. This study is of great significance to the ecological environment protection for the TP. • Contributions of South Asian emissions to PM 10 , PM 2.5 , and O 3 in the TP are quantified. • Anthropogenic emissions in South Asia have a larger contribution to PM 10 , PM 2.5 , and O 3 in the TP. • O 3 from South Asian biomass burning emissions contributes <1% to O 3 in the Tibetan Plateau. [ABSTRACT FROM AUTHOR]

Known as the "third pole" and "water tower of Asia", the Tibetan Plateau (TP) is the home to the largest number of glaciers in the mid-latitudes and one of the most sensitive areas to global climate change due to its special geographical location and powerful thermodynamic effects. In recent years, the TP has been affected by exogenous pollutants and the concentrations of some pollutants have shown an increasing trend, especially light-absorbing aerosols (LAAs), when ice core records, ground- and aircraft-based field campaigns and satellite technology enabled synthesized monitoring. The enhanced warming of the vast majority of regions in TP, together with Arctic warming, and snow/ice decline, represents credible evidence of anthropogenic climate change. This paper provides a comprehensive review of studies on the sources, characteristics and climate impacts of LAAs over the TP. Adjacent to the two major emission sources of LAAs in East Asia and South Asia, the unique geographical location and climatic characteristics of the TP make it possible for TP LAAs to cause atmospheric warming and accelerated glacier melting, affecting the hydrological cycle in South Asia, East Asia and even the Northern Hemisphere, thus causing a series of serious environmental and social problems. LAAs, such as black carbon and dust, can strongly absorb solar radiation and and have significantly influence on climate change. Moreover, light-absorbing impurities (LAIs) on snow/ice can reduce the snow/ice albedo and further accelerate the snow/ice melting. Both LAAs and LAIs over the TP can induce thermodynamic feedback processes, cause significant warming of the TP and then lead to a strengthening of the early monsoon and affect the subsequent evolution of the monsoon. Many mechanisms have been proposed forth regarding how TP LAAs modulate the phase, intensity, and amplitude of the Asian climate system. A wide range of theoretical, observational, and modeling findings on TP LAAs and their climate impacts are synthesized, in which dust aerosols from drylands and black carbon from biomass burning are considered leading components. By coupling an integrated approach with state-of-the-art modeling, high temporal and fine spatial resolution remote sensing observations with increasing sampling over the TP will provide further insights into TP aerosols. • Light-absorbing aerosols warm the Tibetan Plateau, further influence climate system • The external input of light-absorbing aerosols over the Tibetan Plateau is dominant • Climate effects of light-absorbing aerosols or impurities in snow is divergent [ABSTRACT FROM AUTHOR]