I’ve been researching the effects of climate change on ecosystems for 15 years. Even still, I was shocked by the news, earlier this spring, that much of the Western Antarctic Ice Sheet will collapse. Within two centuries, melt water released from the glaciers could raise sea levels by up to 10 feet, scientists say. The potential rise is equivalent to, as one of them said, a permanent Hurricane Sandy storm surge.
Recently, I teamed up with environmental researchers from six universities to explore the potential for “climate engineering” — large-scale strategies to reduce global warming by removing carbon dioxide from the atmosphere or reducing solar input to Earth. We spent the past two years working on the first scholarly attempt to rank these approaches, to see if we could find solutions that offer real hope to “engineer” our way away from human-induced climate change.
We looked at technical feasibility, cost, ecological risk, public opinion, capacity to regulate and ethical concerns. And — at least so far — we can’t engineer away climate change.
Our findings showed that the most effective way is to reduce carbon emissions through fuel conservation, increased energy efficiency and switching to alternative low-carbon fuels. Together, these steps offer the most promise of diminishing the nine gigatons of carbon dioxide being released each year.
Best of all, technologies to take these steps already exist.
So why aren’t we going full force to implement emissions reductions? Certainly, significant economic restructuring would need to happen. There are political and economic hurdles to shifting our energy infrastructure, and consumers get cranky about being told what kind of car to drive.
Another underlying issue is that people like to fix problems — not do less. However, as our study indicated, what’s needed is the hard, unsexy work of reducing emissions. And while some approaches to climate engineering hold promise, their benefits are mostly supplemental.
The best, lowest-risk strategy to complement emissions reductions is helping nature to sequester carbon through biological means. Plants already convert atmospheric carbon into solid materials. Curbing the destruction of forests and promoting growth of new forests could tie up as much as 1.3 gigatons of carbon in plant material annually. Deforestation now adds one gigaton of carbon to the atmosphere each year — but stopping it requires alternative sources of economic growth in developing countries.
Improved soil management is also promising. Over time, agricultural tilling has led to the loss of about half (78 gigatons) of the carbon ever sequestered in these soils. But such simple steps as leaving slash (plant waste left over after crop production) on fields to be incorporated into the soil could reintroduce between 0.4 and 1.1 gigatons of carbon annually to soil. The approach requires a concerted effort across agricultural areas, and is limited by the amount of agricultural land that is actually being farmed.
Applying biochar (or charcoal) to soils, particularly in agricultural areas, could also help. The process, which uses high temperatures and high pressure to turn plants into charcoal, releases little carbon dioxide into the atmosphere. Charred plant material takes longer to decompose and the carbon in plant tissues takes longer to return to the atmosphere as carbon dioxide. To be effective, this approach needs to be global, and is limited to land that is in agriculture.
Another promising strategy is to capture and store carbon below ground from industrial smokestacks, particularly near fuel refineries or power plants. This turns carbon dioxide into a liquid form of carbon, which oil and coal extraction companies can pump into underground geological formations or wells, and cap. Millions of tons of carbon are already being stored this way each year because injecting carbon dioxide into oil fields actually scours more hydrocarbons out of oil fields and allows companies to recover more oil. Applied globally, carbon capture and storage has the potential to store more than one gigaton permanently each year. However, a leak of liquid carbon could be fatal to humans and animals, and the risk — while minimal — may stand in the way of public acceptance.
Even while we work to reduce carbon emissions on a large scale, we can show our willingness as individuals to pay for the carbon we use. I support a carbon tax as a down payment for my own child’s future world. I also pay for voluntary carbon offsets for my fuel use. Although offsets do not directly reduce emissions, some effective programs support things like forest protection and soil management for carbon storage — both identified in my study as promising climate engineering strategies.
While we should not rely on climate engineering to solve the climate change problem, certain strategies do provide feasible, low cost, safe and ethical options — and may help us minimize climate change faster than we are creating it.
This story originally appeared on Zocalo Public Square.