STUDIES ON CARBONACEOUS AEROSOLS FROM A HIGH ALTITUDE SITE IN THE CENTRAL HIMALAYAS

Abstract

Carbonaceous aerosols are very important due to their direct effects on health, radiation budget and their indirect effect in altering cloud properties, thus acting as short term climate forcers. Simultaneous measurements of BC, CO, CH4 and CO2 have particular importance in terms of radiation budget, constraining emission sources and tropospheric chemistry. In this reference, extensive observations of aerosols and trace gases (CO, CO2 and CH4) are carried at ARIES, Manora Peak, (29.4◦N, 79.5◦E, 1958 m amsl). Temporal variations of these species are discussed here. A five particles back-air trajectory analysis from HYSPLIT utilizing residence time of air masses over the defined region of Northern India has been used to correlate simultaneously elevated levels of these trace gases and aerosols. Longitudinal spread of these air masses over different seasons has also been studied. Observations of CO along with BC have also been used to identify the role of different emissions sources. Some episodic events have also been identified and analysed over the period of study. Source identification (mainly wood burning and fossil fuel combustion) using various statistical and chemical methods has also been extensively conducted. More details of this work will be presented.