Measurements of carbonaceous aerosols at urban and remote marine sites

Abstract

Concentrations of total carbon (TC) and black carbon (BC) in ambient air at Delhi (urban site) and over Indian Ocean (remote marine) were determined as a part of INDOEX programme. Over Indian Ocean, the TC and BC concentrations varied from 1.81 to 10.05 μg/m³ and 0.13 to 1.36 μg/m³ respectively during FFP-98. During the same season at Delhi, the TC and BC ranged from 7.50 to 40.27 μg/m³ and 0.49 to 2.84 μg/m³ respectively. In addition, at Delhi, the TC and BC concentrations were noticed very low during the monsoon season. However, the percentage BC during monsoon season was very high compared to winter season. High concentrations of TC were observed due to high organic carbon (OC) which might be due to biomass burning of various kinds. Similar to Delhi, near Indian coast, the concentration of OC was very high while towards ITCZ and across ITCZ, OC content was relatively lower.