Can Humanity Coexist With Rising CO2 Levels?

According to the Working Group III contribution to the IPCC’s Fifth Assessment Report (AR5), without additional efforts to reduce GHG emissions beyond those in place today, emissions growth is expected to persist driven by growth in global population and economic activities with the result, without additional mitigation, global mean surface temperature by 2100 will have increased from 3.7°C to 4.8°C over pre-industrial levels. These are the median values within a range of 2.5°C to 7.8°C and assume CO₂ concentrations of 720 to 1000 ppm compared to 400 ppm today.

The World Bank report “Turn Down the Heat: Why a 4°C Warmer World Must be Avoided,” warns, as the title suggest, such a world must be precluded because it would be marked by extreme heat-waves, declining global food stocks, loss of ecosystems and biodiversity, and life-threatening sea level rise and further that these effects would be “tilted against many of the world’s poorest regions”.

The initial response to the proposition posed by this piece would therefore appear to be no, we cannot coexists with rising CO₂ levels, at lease not the most vulnerable of us and not without mitigation.

Even Royal Dutch Shell’s CEO acknowledged in a recent speech the need for lowering carbon emissions, which he suggests should be accomplished through a carbon-pricing system and a shift from coal to natural gas.

Mr van Beurden claims his industry must make the case that the world’s energy needs will underpin the use of fossil fuels for decades but this is at odds with the recent study published in Nature that 52% of the world’s natural gas reserves, 35% of its oil and 88% of its coal cannot be burned if we are to have a 50:50 chance of remaining below the widely accepted 2^oC safe temperature increase from the pre-industrial base.   

The following visual produced by Rosamund Pearce of the Carbon Brief based on the Nature article, shows the regional breakdown of resources that will have to be left in the ground.

It also highlights how politically difficult it would be to implement such cutbacks. For example oil represents a slightly higher percentage of the Canadian than the U.S. economy, about 5.8% compared to 4.3%, yet Canada would be expected to forego 75% of the economic benefit of its oil reserves as opposed to a U.S. cutback of only 9%.

And then there are the sectoral rivalries. As a producer of natural gas Shell naturally favours its resource over coal but a number of coal producers, such as Peabody Energy in the US,  have pointedly rejected Mr van Beurden’s message that “You cannot talk credibly about lowering emissions globally if, for example, you are slow to acknowledge climate change; if you undermine calls for an effective carbon price; and if you always descend into the ‘jobs versus environment’ argument in the public debate” by labelling efforts on the part of those trying to combat global warming as “alarmism”.

Mr. van Beurden, says that “ineffective, inefficient or even counterproductive measures are taken in some countries and regions” to address climate change, yet the National Research Council and National Academy of Sciences report released just a few days ago suggests  his company’s favoured response to the problem, CCS, falls into the same category. It points out “most carbon dioxide removal strategies have limited technical capacity, and absent some unforeseen technological innovation, large-scale deployment would cost as much or more than replacing fossil fuels with low carbon-emission energy sources.”

The NRC/NAS report also says that albedo-modifying technologies, which aim to increase the ability of Earth or clouds to reflect incoming sunlight, which is the other most widely considered geoengineering strategy, poses considerable risks and should not be deployed at this time either.

Marcia McNutt, editor-in-chief of Science said in a release titled, Climate Intervention Is Not a Replacement for Reducing Carbon Emissions; Proposed Intervention Techniques Not Ready for Wide-Scale Deployment, “That scientists are even considering technological interventions should be a wake-up call that we need to do more now to reduce emissions, which is the most effective, least risky way to combat climate change.”

Fortunately for the Shells, Peabodys and those of us at greatest risk to climate change another recent study in Nature, led by Dean Roemmich of the California-based Scripps Institution of Oceanography suggest another alternative. That study points to the fact the world’s oceans are heating at the rate of two trillion 100-watt light bulbs burning with the result there has been “no significant trend” in mean sea-surface temperatures since 1998, confirming a “hiatus” that deniers of climate science often point to when claiming global warming isn’t happening.

Is it possible Shell, Peabody and others can continue to market their carbon emitting resources provided the oceans continue or increases their heat uptake and what would the result of such an endeavor be?

The Roemmich report relying on an array of about 3500 Argo buoys from 2006-13 shows temperatures warmed at about 0.005 degrees a year down to a depth of 500 metres and 0.002 degrees between 500-2000 metres.

By comparison the NOAA National Climatic Data Centre says the 2006  global annual land temperature was 0.78°C above average and the 2013 land temperature was 0.99°C above average for an increase of about .02625 degrees per year or about 13 times the increase in deep water temperatures. Extrapolating .02625/year out to the end of the century, comes to an atmospheric increase of about 2.25°C, which is 1.45 degrees lower than the 3.7°C minimum the IPCC shows for a business as usual fossil fuel burning scenario.

My take on this is the forcible movement of heat into the deep ocean, whereas the events of 2006-13 have been induced by natural phenomena that are assumed to be temporary, would keep the atmospheric temperature close to the 2°C acceptable limit even if we continued to burn fossil fuels. The consequence to the deep ocean – the 500-2000 meter region – on the other hand would be a negligible increase of .17°C.

John Church, one of the authors the Scripts study says the temperatures in the atmosphere – which accounts for just 1 per cent of the planet’s heat uptake – would rise sharply if oceans absorbed less of the heat.

Conversely atmospheric temperatures would be more gradual if the oceans absorbed more heat as is suggested here can be accomplished economically and to the benefit of the environment.

Heat movement into the ocean deep can produce real, zero-emissions, energy that can run real light bulbs, provide real energy for transportation and heat and air-condition our homes and work places and consequently this is a mitigation strategy that would be self-sustaining.

Rather than investing current profits in future reserves that very well might not be burnable, it is probably in the better interest of the shareholders of fossil fuel companies to invest in technology that best preserves the value of existing reserves and insures the continuation of those companies in the energy business long after the fossil fuel era has ended. This is an approach that would keep atmospheric warming within safe limits as this transition comes about and will relieve fossil fuel companies of their greatest public relations problem in the interim.

This is climate intervention that reduces carbon emission as well as the risk of taking the necessary action, leaving but one hurdle, the politics of trying to figure out the best way to tax planetary salvation.