Sources and variability of non-methane hydrocarbons in the Eastern Mediterranean
The volume mixing ratios of non-methane hydrocarbons including saturated, unsaturated and aromatic ones (C2 to C8 as non methane hydrocarbons, NMHCS) were measured at three distinct sites (natural, rural, urban) in the lower troposphere of the Eastern Mediterranean from February 2006 to March 2007. Average concentrations for most of the NMHC show clear seasonal variations along the year mainly attributed to photochemistry. Significant correlations found among various hydrocarbons indicate contribution from mobile and stationary sources (exhaust and combustion). Leakages from natural gas (NG) or liquefied petroleum gas (LPG) probably from the continental platforms may account for important sources for the background concentration of ethane and propane in the area. Isoprene has been found to have mostly a biogenic source but its dual anthropogenic–biogenic origin was also evident at the rural site.