Natural Volatile Organic Compounds (NVOC) Emissions Inventory

The Natural Volatile Organic Compounds (NVOC) emissions data sets include isoprene (isop90mn1.1a), terpene (terp90mn1.1a), and other natural volatile organic compounds, with a lifetime of less than one day (nvoc90mn1.1a). All of the data sets are on a monthly basis for the year 1990 on a one degree latitude by 1 degree longitude grid. NVOC emissions include isoprene, monoterpenes, other reactive VOC (ORVOC), and other VOC (OVOC). VOCs are emitted into the atmosphere from natural sources in marine and terrestrial environments. Natural sources of VOC emissions to the atmosphere include marine and fresh water, soil and sediments, microbial decomposition of organic matter, geological hydrocarbon reservoirs, plant foliage and woody material, and enhanced emissions from vegetation during harvesting or burning. NVOCs are important in tropospheric chemistry and in the global carbon cycle. VOC emissions are critical in controlling the OH concentration of the troposphere and so may play a major role in determining the growth rates of atmospheric CH4 (methane) and CO (carbon monoxide) concentrations. Several emissions inventories of VOCs have been published and they indicate that annual natural emissions of isoprene
and monoterpenes exceed anthropogenic VOC emissions on a global scale. Each line of data in the GEIA inventory consists of an integer grid number and real specie values for the temporal resolution of the data (one month). Each file contains at most 360 x 180 data lines.