IEA, International Energy Agency: "[Gas] puts emissions on a long-term trajectory consistent with stabilising the concentration of greenhouse gases in the atmosphere at around 650 ppm, suggesting a long-term temperature rise of over 3.5°C"

The International Energy Agency (IEA) in its own words: “The IEA is an autonomous organisation which works to ensure reliable, affordable and clean energy for its 28 member countries and beyond. The IEA's four main areas of focus are: energy security, economic development, environmental awareness, and engagement worldwide” (see: http://www.iea.org/aboutus/ ).

IEA World Energy Outlook 2011 special report, “Are we entering a Golden Age of gas” (2011), Summary, pp8-9: “An increased share of natural gas in the global energy mix is far from enough on its own to put us on a carbon emissions path consistent with an average global temperature rise of no more than 2°C. Natural gas displaces coal and to a lesser extent oil, driving down emissions, but it also displaces some nuclear power, pushing up emissions. Global energy-related CO₂ emissions in 2035 are only slightly lower than those in the New Policies Scenario, at around 35 Gt [CO₂-e]. This puts emissions on a long-term trajectory consistent with stabilising the concentration of greenhouse gases in the atmosphere at around 650 ppm, suggesting a long-term temperature rise of over 3.5°C. To limit the increase in global temperature to 2°C requires a greater shift to low-carbon energy sources, increased efficiency in energy usage and new technologies including carbon capture and sabotage. The GAS Scenario assumes that support for renewables is maintained but, in a scenario in which gas is relatively cheap, there is a risk that governments’ resolve in this respect might waiver, pushing gas demand even higher than projected here. ” [1]

{1]. IEA World Energy Outlook 2011 special report, “Are we entering a Golden Age of gas” (2011): http://www.worldenergyoutlook.org/goldenageofgas/ .