Depending on the scenario, we need to sequester 100-1000 Gigatonnes of CO₂, to reach the 1.5° goal and maintain a good life on earth.
So, if we can reach 205 Gigatonnes of carbon sequestration by afforestation, that accounts for roughly 750 Gigatonnes of CO₂. But the IPCC warns that this may likely be in competition with food production. The same problem exists with planting bioenergy crops on croplands to feed bioenergy with carbon capture and storage facilities (which are far from beeing applicable on the scale needed).
But trees already existing on agricultural land worldwide now store about 36 Gigatonnes of carbon or 133 GT of CO₂. If we triple that amount, we could put additional 267 GT of CO₂ back into the soil. If we manage to have ten times as much trees on agricultural land as we have now, that would sequester 1197 Gigatonnes of CO₂ out of the atmosphere.
With my project baumfeldwirtschaft.de and the help of engaged farmers, we planted 100 times more trees in their croplands than there were before. And these trees – chestnuts, nuts and fruits – produce staple foods! Furthermore, the soil now is safe from erosion, the humus isn’t destroyed anymore but more is built up (even more carbon put in the soil), water is retained and accessible in dry summers, so that in the end even the crops grown between the trees deliver higher yields.
So we demonstrated here in central Europe, right outside Berlin, that it is possible to reach the 1.5° goal AND enhance food security, rural livelihoods, ecosystem services, water retention, biodiversity etc. It is possible – if we implement such agroforestry systems with tree crops on landscape scale.
Think about what you eat and buy… Maybe you can support local farmers in planting tree crops?
A significant change in the landscape, that has the power to fight climate change: A keyline pattern agroforestry system with tree crops for staple food production. Where there was barren cropland, now trees protect the soil and build up humus and water retention.
Sources:
Bastin, Jean-Francois, et al. 2019. The global tree restoration potential. Science. 2019, Bd. 365, 6448, S. 76-79.
IPCC. 2019. Climate Change and Land – An IPCC Special Report on climate change, desertifcation, land degradation, sustainable land management, food security, and greenhouse gas fluxes in terrestrial ecosystems. https://www.ipcc.ch/report/srccl/ Geneva, Switzerland : IPCC, 2019.
—. 2018. Global warming of 1.5°C. An IPCC Special Report on the impacts of global warming of 1.5°C above pre-industrial levels and related global greenhouse gas emission pathways, in the context of strengthening the global response to the threat of climate change. Geneva, Switzerland : IPCC, 2018.
Zomer, R.J., et al. 2016. Global Tree Cover and Biomass Carbon on Agricultural Land: The contribution of agroforestry to global and national carbon budgets. Nature Scientific Reports. 2016, 6 (29987).