The projected CO2 concentration may reach 850 ppm by the end of the 21st century (Nakicenovic & Swart, 2000), which is about triple of the pre-industrial concentration level (280 ppm). The global emission scenario B2 describes a world with intermediate population and economic growth, emphasizing local solutions to economic, social, and environmental sustainability. According to the B2 scenario, the projected CO2 concentration is likely to exceed 600 ppm (Nakicenovic & Swart, 2000), which is somewhat larger than a double concentration level relative to the pre-industrial CO2 conditions. A1B emission scenario estimates the CO2 level reaching 717 ppm by 2100, which.
