Our carbon debt is accruing interest.
The International Panel on Climate Change (IPCC) reports that the atmosphere can take another 1000 Giga tons of CO2 before we reach our target of 2ºC of global warming. If our current rate if emissions remains static, this threshold will be reached in 30 years and no further CO2 emissions can be released.
Cheap energy = environmental trouble
We are releasing emissions at an unsustainable rate; there is some debate over whether the impact of a two degree temperature rise is too great; depending on the exact eco-system tipping point, the anticipated consequences include extreme weather conditions, severe droughts, floods, water shortage, food shortage, social unrest, mass emigration, riots and financial meltdown; we will be at war with ourselves fighting for survival.
US president Barack Obama recently said that this is the first generation to notice the effects of global warming and the last generation to be able to do something about it. I agree, the consequences will be personal and extreme.
I believe we got to this situation due to an open loop control issue, we use way too much energy and we are not charged for the environmental consequences of it. If energy costs were say 10 times greater, we would think twice about: flying, driving, heating / cooling set points, insulation, leaving lights / computers on, etc., etc. Then we might have some money for research and development of renewable energy, and reduction programmes of energy use and embodied environmental impact of products and systems.