Emissions of carbon dioxide, the main greenhouse gas from human activities, are the subject of a worldwide debate about energy sustainability and the stability of global climate.
Carbon dioxide constitutes a tiny fraction of the earth’s atmosphere - about one molecule in three thousand - but is the single largest waste product of modern industrial society. View graph for an overview.
The concentration of carbon dioxide in the atmosphere has risen from about 280 parts per million by volume to the current level of over 360 parts per million by volume and anthropogenically caused atmospheric concentration of methane has doubled. In the past 100 years, levels of nitrous oxide have risen about 15%. Increasing concentrations of greenhouse gases trap more terrestrial radiation in the lower atmosphere (troposphere), artificially enhancing the natural greenhouse effect. The average temperature of the Earth has warmed about 1°C since the mid-19th century when measurements began, and fragmentary records suggest the Earth is warmer than it has been in nearly 2,000 years.
The expected repercussions of climate change – including rising sea waters, more frequent and intense storms, the extinction of species, worsening droughts and crop failures – will affect every nation on earth.
Renewable energy provides a new avenue for rural economic development, increases the tax base, insures against rising or variable fuel costs, decreases dependence on foreign energy sources, and offers numerous environmental benefits.
As compared to traditional fossil fuels, renewable energy is a labour-intensive sector that generates a wide variety of high-wage and high-skilled jobs in the areas of research and development; design and manufacturing; construction and installation of power-generating facilities; cultivation and collection of fuel in the case of biomass; and operation and maintenance jobs. In addition to providing good returns on investments, renewable energy could create thousands of jobs, increase incomes in rural areas, and generate additional tax revenue.