Our results imply that clearly, forests play a critical role in Earth’s terrestrial carbon balance, and exert considerable control over the evolution of atmospheric carbon dioxide. — David McGuire, Institute of Arctic Biology
Humans add about 30 gigatons of Carbon Dioxide (CO2) to the atmosphere each year but only 40% of this additional CO2 can be absorbed by natural carbon sinks like forests, oceans and wetlands. The rest — about 18 gigatons of CO2 — is added to the atmosphere year after year. And with each year, this added CO2 is building a thicker and thicker layer of insulation around the planet, trapping more of the sun’s heat as a result.
It’s clear we need to dramatically reduce the amount of CO2 we emit by investing in energy efficiency and replacing polluting fossil fuels with clean sources of energy like wind power and solar power. But even if we were to cease all CO2 emission tomorrow, we would still have a lot of accumulated CO2 in the atmosphere to deal with. And for that we need carbon sinks.
Oceans are capable of sequestering about 25% of current annual CO2 emissions, leaving the balance to terrestrial carbon sinks. Until recently scientists were not sure how much and exactly where carbon is stored on land, but in a landmark study by the University of Alaska Fairbanks Institute of Arctic Biology, released in 2011, it was shown that forests account for almost all of the world’s land-based carbon uptake, with boreal forests sequestering 22% of the carbon stored in the forests.
Tragically, climate change and tropical deforestation are placing these carbon storage sinks in grave peril. In northern latitudes warming temperatures and drought are leading to increased fires and insect damage. And in the tropics, deforestation is not only contributing more than 15% of total global CO2 emissions, but it is destroying the continued ability for those forests to absorb CO2.
It is clear that we need to do everything we can to protect and preserve our forests — through Avoided Deforestation, Reforestation (restoring denuded forests), and Afforestation (planting new forests). However we need to ensure that these vitally important measures are not used as “loopholes” for developed nations to avoid their climate mitigation responsibilities. Protecting and preserving our forests is a cornerstone in solving the climate crisis, but we need to do much more.
If you could continually turn a lot of organic material into biochar, you could, over time, reverse the history of the last two hundred years. – Bill McKibben
One very ancient technology has resurfaced as a potential solution to neutralize our excess CO2 emissions — biochar. Biochar is a type of coal made by pyrolysis, burning biomass waste in low or zero oxygen conditions. The result is solid, sequestered carbon called terra preta which enabled pre-Columbian Amazonians to build soil fertility even under harsh conditions by stimulating the growth of friendly fungi and earthworms.
Modern versions of this ancient technology are currently under development and could, according to NASA scientist James Hansen, cut global atmospheric concentrations of CO2 by 8 parts per million.
- Worldwide use of biochar could cut CO2 levels by 8 parts per million within 50 years, according to NASA scientist James Hansen. [CNN]
- Biochar helps clean the air two ways: by preventing rotting biomass from releasing harmful CO2 into the atmosphere, and by allowing plants to safely store CO2 they pull out of the air during photosynthesis. [CNN]
- According to experts, billions of tonnes of carbon could potentially be sequestered in the world’s soils, specifically from agriculture and forestry residual biomass. [guardian.co.uk]
- Biochar, a form of charcoal, increases growth in crops, and also absorbs and contains carbon dioxide. [Have It Green]
- The smaller pores in biochar trap carbon better than other types of charcoal. Thus, it has been estimated that biochar can store carbon dioxide for up to 5,000 years.[Have It Green]
- The use of biochar, as well as the manufacturing process, is actually carbon negative and could prove to be beneficial towards reducing global carbon emissions.[Have It Green]
- In addition to holding in carbon dioxide, biochar is an efficient fertilizer for farming. Crops that have been tested using the biochar as a fertilizer dramatically increased crop yields. [Have It Green]
- Biochar was originally used by Natives in the Amazon Basin approximately 7,000 years ago. While the Natives used this fertilizer due to the apparent increase in crop growth, the carbon absorbing nature of biochar was unknown until recently.[Have It Green]
- “We’re finding that the carbon in biochar has a residence time of at least 2,000 to 2,500 years. That’s what we can identify so far. If you bury that, it’s not going to get back into the atmosphere anytime soon.” – Jason Amburu, Re:Char
- “If you could continually turn a lot of organic material into biochar, you could, over time, reverse the history of the last two hundred years.” –Bill McKibben, 350.org
- “[Biochar] has not only consequences for mitigating climate change, but also for agricultural sustainability, and could provide a strong incentive to reduce deforestation, especially in the tropics.” – Christoph Steiner, Biochar.org
- “Biochar has enormous potential. When scaled up, it can take out gigatons of carbon from the atmosphere.” – John Mathews, Macquarie University
- “Biochar can be used to address some of the most urgent environmental problems of our time- soil degradation, food insecurity, water pollution from agrichemicals, and climate change.” – Johannes Lehmenn, Cornell University, Chairman of the International Biochar Initiative Board of Directors
There are no comments yet. Why not be the first to speak your mind.
About the AuthorKarl Burkart is the Digital Communications Director for the GCCA, the Global Call for Climate Action, and TckTckTck, a network of 400+ diverse organizations working around the world for greater action on the growing problem of climate change. Karl also blogs on technology and the environment for a variety of publications. You can follow him on Twitter @greendig.
View Author Profile