Climate Change is the change in climate (i.e. regional temperature, precipitation, extreme weather, etc.) caused by the increase in the greenhouse effect.
Greenhouse effect is the process wherein greenhouse gases (such as water vapor, CO2, methane, etc) in the atmosphere absorb and re-emit heat being radiated from the earth, trapping warmth.
Greenhouse Gases refers to gases that contribute to the greenhouse effect by absorbing infrared radiation (heat).
With energy-related carbon dioxide (CO2) representing the majority of global greenhouse gas (GHG) emissions, the fight against climate change has become a defining factor for energy policy-making – but the implications are daunting. Meeting the emission goals currently pledged by countries under the United Nations Framework Convention on Climate Change (UNFCCC) would still leave the world some 13.7 billion tonnes of CO2 – or 60% – above the level needed to remain on track with the 2°C goal in 2035. The much additional investment will need to be directed towards lower- CO2 technologies, on supply and end-use sides alike. The benefits that society would reap from these measures, beyond avoided climate impacts, would be of an equal if not larger magnitude than the cost to the energy sector. Meanwhile, energy policy-makers need to start thinking about the impact of committed climate change on the security of the energy sector.
Governments have decided collectively that the world needs to limit the average global temperature increase to no more than 2°C and international negotiations are engaged to that end. Yet any resulting agreement will not emerge before 2015 and new legal obligations will not begin before 2020. Meanwhile, despite many countries taking new actions, the world is drifting further and further from the track it needs to follow.
The energy sector is the single largest source of climate-changing greenhouse-gas emissions and limiting these is an essential focus of action.