key areas can reduce the effective emissions due to pumping the carbon dioxide into oil beds or coal beds to enhance the recovery of oil and methane. Carbon dioxide is a greenhouse gas, so the increased carbon dioxide produced from both the more involved extraction process with unconventional oil, as well as burning the oil itself, has led to deep concerns about unconventional oil worsening the impacts of climate change. Economics Sources of unconventional oil will be increasingly relied upon when conventional oil becomes more expensive due to depletion. Conventional oil sources are currently preferred because they are less expensive than unconventional sources. New technologies, such as steam injection for oil sands deposits, are being developed to reduce unconventional oil production costs. In May 2013 the IEA in its Medium-Term Oil Market Report (MTOMR) said that the North American oil production surge led by unconventional oils - US light, tight oil (LTO) and Canadian oil sands - had produced a global supply shock that would reshape the way oil is transported, stored, refined and marketed. See also Unconventional (oil & gas) reservoir Extreme energy Renewable energy Future energy development Hubbert peak Energy development Alternative fuels Fischer–Tropsch process Synthetic Liquid Fuels Program World energy resources and consumption Oil Megaprojects Unconventional wind turbines Unconventional gas Notes References Further reading External links Unconventional Resources Centre For Energy World CTL Peak oil Petroleum production Synthetic fuels