Why zero emissions?
What is Zero Emissions and Below?
"There is too much greenhouse gas in the air NOW! There is absolutely no advantage in having any more in the air, NOW! Our private targets should be to have no future emissions in to the atmosphere. That's what we really need."
Philip Sutton, Greenleap Strategic Institute
The phrase “Zero Emissions and Below” describes the goal of reducing human greenhouse gas (GHG) emissions to zero(i) in order to reduce our emissions below the level of natural sequestration of GHG.
When this point is reached, natural systems will be sequestering more carbon than is being released into the atmosphere – therefore levels of atmospheric GHG will reduce.
However we need to speed this process up as fast as we can by employing human sequestration options, such as increasing soil carbon levels through organic agriculture or carbon uptake by regrowing forests on previously cleared land. Otherwise we will be stuck with dangerously elevated temperatures for many hundreds of years.
The process must be continued as fast as possible until atmospheric GHG are reduced to close to pre-industrial levels, which would over time re-establish the relatively stable climate the planet has experienced for the last 8000 years.
The “Zero Emissions and Below” goal is also described as “Zero Emissions Minus”, “Zero Minus” or “Zero Minus Fast” goals.
(i) In reality we might only get an outcome of 97-100% reduction in different sectors, but note the 97% figure is not the goal but an outcome of working towards a 100% zero emissions goal.
How low do we go?
Our goal is to achieve zero emissions as fast as possible and maximise both natural and human sequestration of atmospheric GHG.
Importantly the goals we aim for need to be significantly tougher than the goals that global society is pursuing, because we know from experience that individual and organisational efforts often fail – so each of us have to over-compensate. Our personal, organisational and regional (i.e. Australian) goals must be as strong as they can be.
Below I have outlined one possible scenario.
Currently natural sequestration is estimated to occur at around 4 billion tons (Gt) of carbon a year. Higher temperatures are expected to seriously reduce the natural sequestration rate by mid-century. One estimate is that it will reduce to 2.7 Gt per year by 2030. Let’s say we choose a figure of initially reducing atmospheric greenhouse gases by 3 Gt of carbon a year, then we are left with 1 Gt of carbon emissions to distribute across the entire world population to deal with meeting emissions that have not yet been reduced to zero.(ii)
The world population is 6.5 billion and by using the principles of equitable global carbon rationing(iii), where allowable carbon emissions (1 Gt) are divided up on a per capita basis, Australia would be allowed to produce O.15 tC per person or 3.1 million tons (Mt) of carbon (11.4 Mt of CO2) as a nation per year.
We currently produce 564.7 Mt of CO2e (2004 figure), and therefore we would need to reduce today's GHG emissions by 98% to meet our allowance of 11.4 Mt of CO2e.(iv)
Human assisted sequestration would be used to maximise the rate of atmospheric GHG removal.
To put these figures in the context of the standard “X% of 1990 levels by 2050”, it would mean Australia must reduce its carbon emissions by 98% on 1990 levels. This assums a world population of 9 billion and a continued shared desire to produce no more than 1 Gt of carbon per year globally with all nations moving simultaneously to reach similar carbon rationing based targets.
Even if we merely wanted our emissions to be “Net Zero” or “Carbon Neutral”, i.e. having no net effect on atmospheric GHG levels we would still need to reduce our current GHG emissions by 92%, and we would be resigning ourselves to climate impacts worse than we already see today, because of the additional 0.5-1.5º temperature rise already built in.(v)
(ii) The decision to reduce atmospheric GHG by 3 Gt per year is largely an arbitrary decision on my behalf and in reality should be as high as we can make it. It must be supplemented by human assisted sequestration to maximise the rate of atmospheric GHG reduction. Food production would be expected to utilise a significant proportion of the allowable GHG emissions.
(iii) The question of compensation for the damage to the world climate systems by the developed nations (who are responsible for releasing most of the GHG from fossil fuel burning and deforestation) is still not dealt with by the carbon rationing system. The developed world must pass on and fund the roll out of zero emissions technologies, prevent further land clearing and aid in adaptation programs for developing nations. A non carbon based economy needs to be established in the developing world as ultimately the carbon economy has no future. Investment in carbon economy technology for the developing world would only disadvantage them in the long run and slow the global move towards zero emissions.
(iv) I have converted our allowable CO2 emissions directly into an allowable CO2e or “carbon equivalent” figure. This allows a comparison against the figure for total GHG emissions in CO2e from Australia's GHG inventory but ignores in the initial calculation of allowable emissions the natural sequestration or decomposition of other GHGs, most notably methane which only has an average life of 12 years in the atmosphere. If we restricted our analysis to purely CO2 emissions, the figure for CO2 released in 2004 is 415 Mt CO2 which would require a 97.25% reduction in our CO2 emissions to still restrict global emissions to 1 Gt C per annum. If we wanted to tread water (in the ever rising seas) and go for “carbon neutral” looking at CO2 only, then we would need to reduce today's CO2 emissions by 89% immediately (calculation below).
Natural carbon sequestration of 4Gt of carbon per annum divided by a world population of 6.5 billion gives us .615 t C per capita per annum, multiplying this by Australia's population of 20.25 million gives us an annual figure of 12.46 Mt of carbon which can be released into the atmosphere. Multiply this by the carbon to carbon dioxide weight conversion factor of 3.6675 gives us a total annual figure of 45.7 Mt of CO2 allowable for release into the atmosphere. Converting this figure to a percentage of our total CO2 released per year (451.05 Mt , or 45.7/415.05*100) gives us a goal of 11% of CO2 emissions or an 89% immediate reduction.
(v) The 92% carbon neutral figure would increase in size each year we delay reducing our emissions, and would also have to increase over time as the earth's natural systems lose their ability to absorb atmospheric carbon, a process which is occurring now.
How fast do we go?
The simple answer is as fast as possible, which in Australia we believe is ten years, with a crash program.
We also need to go as fast as possible to take a leadership role in the world showing that a country such as Australia, which until now has been dependent on coal for power and export dollars can go zero emissions.
The ten year figure also matches numerous calls by leading scientists, including James Hansen, NASA's leading climate scientist, who say we have ten years to significantly reduce our emission levels or we are in serious trouble.
"The crystallising scientific story reveals an imminent planetary emergency. We are at a planetary tipping point. We must move onto a new energy direction within a decade to have a good chance to avoid setting in motion unstoppable climatic change with irreversible effects. The ‘dangerous’ CO2 level is at most 450 ppm, and it may be less. CO2 has already increased from pre-industrial 280 ppm to today’s 383 ppm, and it is now increasing about 2 ppm per year. Global disasters can still be avoided, but only if we act promptly."
James Hansen, State of the Wild: Perspective of a Climatologist, April 2007
Why a fast transition to Zero Emissions and Below?
1. A moral and ethical imperative
If you simply look at the impacts of climate change today which include species extinction, 150 thousand or more human deaths per year, ecosystem collapse, catastrophic weather events, drowning pacific islands and growing numbers of climate refugees, in any moral or ethical analysis it is difficult to argue that we should allow the situation to remain the same or even get worse.
Consequently the only logical response open to those holding a moral and ethical position on climate change is that we must reduce the level of atmospheric greenhouse gases and to do this as fast as possible to reduce future impacts. This is especially true given that many of the solutions are available for implementation today.
To argue for anything less is to advocate an increase in the impacts we are observing today and exposing the world to unacceptably high risks of catastrophic or cataclysmic climate change (see points 2 and 3 below).
2. Avoiding catastrophic climate change
Numerous scientific, environmental and political organisations, including the European Union, have been arguing that the critical level of dangerous climate change is 2º above pre-industrial levels.
As we approach this point climate change will move from highly damaging to having a catastrophic impact on the world's ecosystems and human society.
We will see the death of much of the world’s coral reef systems, 20-30% of the world species going extinct, human populations with significantly reduced water availability, committing Greenland to a near complete melting and consequent floating off of the West Antarctica ice sheet, the loss of the Amazon Rainforest and much much more.
On the most optimistic reading of the science we already have a 10% chance on reaching a 2º warming.(vi) Any policy that sees GHG levels increasing, increases the risk of reaching a 2º warming, which is clearly too high already.
For example at current rates of atmospheric carbon increase we will reach 450 ppm CO2e around 2013. At that point it is estimated that we will have a 26-78% chance of having a 2º temperature rise.
If we wish to reduce these risks then our only option is to advocate a reduction in atmospheric GHG levels.
(vi) See the Climate Risk Analysis complied by the Greenleap Strategic Institute based on page 195 of the Stern report and further commented upon by Beyond Zero Emissions: http://beyondzeroemissions.org/climate-risk
3. Avoiding cataclysmic climate change and a runaway event
If we reach an 6-8º or more temperature increase, climate change will result in truly cataclysmic impacts on humanity and the environment.
This figure could be reached if a critical number of positive feedback loops become active and start a chain reaction of GHG increases, temperature rise and further triggering of positive feedback loops.
Some of these positive feedback loops include the melting of the North Pole, the thawing of the world's permafrost, the drying and burning of the Amazon rainforest, gasification of undersea frozen methane, significant changes to ocean currents and ocean acidification.
The point at which the world passes the critical threshold of GHG gas release from positive feedback loops is called the “tipping point”.
The exact timing of the “tipping point” can only be guessed at, with some scientists such as Lovelock arguing we have already passed it, while others argue it will occur if somewhat higher temperatures are reached. James Hansen from the NASA Goddard Institute thinks the tipping point might be as close as a further 1º away from the current temperature and we are already perilously close to locking in that additional warming.
Giving the uncertainty around the point at which we will pass the global “tipping point”, the only logical approach to dealing with this phenomenon given its disastrous impacts is to reduce our atmospheric GHG levels as quickly as possible and hence reduce the risk of this event occurring.