One of the most worrsome obstacles preventing people and governments from fully appreciating the consequences of their carbon dioxide emissions is a condition that climatologists call “climate lag,” the “thermal inertia” which delays by about 40 years the warming effect of rising levels of atmospheric greenhouse gases.
This means the climate we are getting in 2016 was generated about 1976 when atmospheric carbon dioxide concentrations were 334 parts per million, and the future climate for our children in 2055 will be based upon the 400 ppm we have today.
This 40-year delay, calculated by one of the world’s foremost climate experts, James Hansen, is an approximation based on a transition period extending from 25 to 50 years. Since the median is 37.5, a simplified estimate is 40 years.
Climatologists know the average global temperature has increased 0.8°C from the accumulated carbon dioxide emissions since 1990. Because we have yet to receive most of the effects of our emissions during the last 40 years, climate lag will eventually add another 0.6°C to this increase.
Since global CO2 emissions are still going up rather than down (0.5 per cent in 2014), we will very likely surpass the 2°C maximum temperature increase agreed to by the world community.
If the weather extrems we are getting now make us uneasy, the weather eventually generated from our current emissions will be considerably more disquieting.
Neither will we like the permanence of these new conditions. About one-third of all carbon dioxide we emit is added to the atmosphere and will stay there for at least 1,000 years before being safely sequestered by natural processes.
From the perspective of our civilization, the climae change we are causing is essentially permanent.
The good news for many of us alive tofay is that the full consequences of our present emissions will not be known for another 40 years.
The bad news is that it will be our bequest to future generations.
– Campbell River Mirror