The generally conservative International Energy Agency has shown that we soon will reach the point where we are virtually 'locked in' to at least 2 degrees of warming:
Four-fifths of the total energy-related CO2 emissions permitted to 2035 in the 450 Scenario are already locked-in by existing capital stock, including power stations, buildings and factories. Without further action by 2017, the energy-related infrastructure then in place would generate all the CO2 emissions allowed in the 450 Scenario up to 2035. Delaying action is a false economy: for every $1 of investment in cleaner technology that is avoided in the power sector before 2020, an additional $4.30 would need to be spent after 2020 to compensate for the increased emissions.
But that doesn't mean we should just give up - and nor that we should delay further action for two decades. On the contrary it points to the importance of more action more quickly to shift to clean energy.
Note also the last sentence in the above quote - about the false economy of delaying action.
