My grandchildren began to influence me when I realized that policy makers were ignoring the message from the climate science, or rather that politicians were developing the fine art of greenwash — they would say favorable words about the environment and stabilizing climate, but their actions were inconsistent with that goal.
Politicians would be happy if scientists just tell them there is a climate problem and then go away and shut up. Let them decide what they want to do.
But I decided that I did not want my grandchildren, some day in the future, to look back and say, "Opa understood what was happening, but he did not make it clear."
What is clear is that we cannot burn all the fossil fuels. There is a limit on how much carbon we can put into the atmosphere.
When we inject a pulse of carbon dioxide into the atmosphere by burning fossil fuels, the carbon dioxide begins to disappear quite rapidly.
After 25 years, about half of it has been taken up by the land and ocean, mostly by the ocean. However, the ocean will not take up the full carbon dioxide emissions, because the carbon dioxide entering the ocean exerts a "back pressure" on the atmosphere — it can come back out. Until the excess carbon is deposited on the ocean floor as carbonate sediments, the ocean will not take up all of the fossil fuel emissions, and formation of those sediments takes thousands of years.
The climate and geophysical facts yield a remarkably well-defined and important conclusion. The story is summarized in the two parts of this figure.
The bar graph shows the carbon contained in all fossil fuels, with purple indicating portions that have already been burned. The blue portions are estimated economically recoverable reserves, which each have substantial uncertainty.
What is economically recoverable depends strongly upon policies, e.g., whether fossil fuels are subsidized or, in contrast, a growing carbon price is adopted.
Coal: The IPCC reserve estimate for coal is almost surely too large, and even the World Energy Council (WEC) estimate may be too high. But there is more than enough coal to take the world far into the realm of dangerous climate change.
Oil & Gas: Oil and and gas reserves that are actually exploited might be kept closer to the IPCC estimates via a rising price on carbon emissions. The larger reserve estimates of the Energy Information Administration (EIA) may be realistic if a policy is pursued to extract every last drop of oil in the ground from public lands, off-shore areas, the deep ocean and polar regions.
Unconventional Fuels: Unconventional fossil fuels, such as tar sands, oil shale and methane hydrates, potentially contain an even greater amount of carbon, but most of these could be left in the ground — if a sufficiently high price on carbon emissions is established.
The second chart compares actual atmospheric carbon dioxide history with carbon cycle simulations based on a dynamic-sink pulse-response function representation of the Bern carbon cycle model (Joos et al., 1996; Kharecha and Hansen, 2008).
The important point is that atmospheric carbon dioxide will peak at a value somewhere in the range 400 ppm to 425 ppm — if coal emissions are phased out by 2030 and if unconventional fossil fuels are not used significantly.
Improved forestry and agricultural practices could bring carbon dioxide below 350 ppm by the end of this century via actions that draw down atmospheric CO2 — if IPCC estimates for oil and gas reserves are valid, meaning a sufficient price is placed on carbon emissions to discourage extraction of every last drop of oil and gas.
These graphs tell us unambiguously that we must phase out coal emissions rapidly, not develop the unconventional fossil fuels, and not even go after every last drop of oil on the planet if we want our children and grandchildren to have a chance of inheriting a planet that is not spiraling out of their control.
In reality, our governments are continuing to build new coal-fired power plants, develop unconventional fossil fuels, and encourage the search for more oil.
Instead of taking a strategic approach, governments pretend that they will solve the problem by setting "goals" for large emission reductions for some future date, say 80 percent by 2050 or some other target. They say that they will set "caps" on emissions to achieve the emission reductions.
Our governments are lying to us, or, if you want to be generous, they are kidding us. That is easy to prove.
These graphs show how emissions will decline if coal use is phased out linearly over the next 20 years and if unconventional fossil fuels are prohibited. The two results (blue and red lines) are for the modest oil and gas reserves estimated by IPCC and for the larger reserves estimated by the United States Energy Information Agency.
With the small oil and gas reserves, depletion of those reserves will cause carbon emissions to fall to 20 percent of current emissions by 2050 and to 40 percent with the government estimates of oil and gas reserves. But that is assuming 100 percent coal phaseout and no use of unconventional fossil fuels. In reality, governments are not phasing out existing coal emissions, instead coal emissions are increasing. And governments are allowing unconventional fossil fuels to be developed.
Thus it is inconceivable that government "goals" or "targets" for carbon dioxide emission reduction will be met. Governments stating such goals are lying to the public with a straight face.
Preservation of a healthy planet, with a stable climate and containing most of today's species, is technically feasible. But it requires prompt phase-out of coal emissions. And it requires a rising price on carbon — that is the only way that we can transition to the cleaner, healthier world beyond fossil fuels.
But what is actually happening? It is quite the opposite, despite the presence of many greenwashing politicians. Here is a representative nation — the United States.
Despite the rhetoric about a planet in peril, the reality is that fossil fuel companies are still calling the tune. We, the taxpayers, are still subsidizing fossil fuels. And fossil fuel companies are not made to pay for the damage that they do to human health or the planet's health.
The present situation is analogous to that faced by Lincoln with slavery and Churchill with Nazism — the time for compromises and appeasement is over.
But today we have no great leader with the intestinal fortitude to stand up to the special interests.
Adapted from "Global Warming Time Bomb: Actions Needed to Avert Disaster," presented in Amsterdam on Oct. 26, 2009.