Press release: Rainforest protection also with economic value
No. 112 - 19.07.2023
Researchers compare real forest losses with simulated agricultural decisions
(pug) Rainforest destruction means not only loss of biodiversity, but also high social costs from greenhouse gas emissions. Tropical forests sequester carbon from our atmosphere, mitigating the progression of climate change. Loss of tree cover in tropical forests due to agricultural activities releases CO2. An international team of researchers from the universities of Göttingen, Exeter, Wageningen and London School of Economics led by the Technical University of Munich (TUM) has quantified changes in forest loss and determined their economic impact. Their conclusion: Previous forest protection measures in the tropics have a great economic value and save the global community billions of euros. The results were published in the journal Nature Sustainability.
The international community is intensively discussing how to reduce forest losses. However, it is not easy to assess whether previous forest protection measures, such as legislative changes, have been effective at all. One needs a reference scenario that maps expected forest losses without the influence of forest protection measures. While such references have so far been derived from statistical models, the research team has for the first time conducted a simulation of deforestation decisions based on market signals, i.e. reflecting purely economic interests. Different simulated agricultural decisions in Brazil, the Democratic Republic of Congo and Indonesia resulted in an independent reference scenario. By comparison with actually observed forest loss based on analysed satellite data, clear trends in tropical forest loss emerged in the countries considered: In relation to the reference scenario, at times significantly less rainforest loss could be detected after legislative changes for forest protection (Brazil) and stricter controls (Indonesia), but also increased forest loss after election promises (Indonesia) or during armed conflicts (Democratic Republic of Congo).
The new simulation model also takes into account saved and additional CO2 emissions. These emissions cause damage through further warming. Higher temperatures lead to rising sea levels, more frequent weather extremes and increased health problems. All of this can lead to property and infrastructure damage, as well as agricultural yield and crop losses. The future damage associated with CO2 emissions is called the social cost of carbon. Avoided forest losses reduce social costs and thus represent a social value. In the new computational model, saved and additional emissions from changes in rainforest loss are considered. The mathematical models processed data from 2000 to 2019. Because reductions in forest loss occurred temporally before increased forest loss, the researchers were able to demonstrate a high social value of temporarily reduced deforestation using their dynamic valuation method. The results clearly showed that avoided losses are always valuable, even if there is a future risk of loss to the forest and its carbon.
"In our model, we assess the social economic value of temporary reductions in forest loss in Brazil and Indonesia at 92.2 billion euros," explains ProfessorThomas Knoke from TUM. "Forest conservation measures, even those with a more short-term effect, always have a positive economic value. Every ton of CO2 sequestered by tropical trees mitigates the effects of climate change and reduces economic damages in the future."
Professor Carola Paul, Department of Forest Economics and Sustainable Land-use Planning at the University of Göttingen, highlights the positive effects of rainforest protection: "Temporary successes in forest protection are of course not sufficient in the long run. However, our study is encouraging in that any protection of tropical forests is also economically valuable. Remarkably, the social value of climate regulation through forest protection exceeds the private economic benefits of forest clearing."
Original publication: Thomas Knoke et al. Trends in tropical forest loss and the social value of emission reductions. Nature Sustainability (2023). DOI: 10.1038/s41893-023-01175-9
Contact:
Professor Carola Paul
Georg-August-Universität Göttingen
Department of Forest Economics and Sustainable Land-use Planning
Büsgenweg 1, 37077 Göttingen
Phone: +49 551 39-26762