Oil crops significantly impact global land use, with palm oil being particularly criticized for contributing to the loss of tropical forests. A recent study by CMCC and Politecnico di Milano suggests an alternative to the simplistic substitution of palm oil with other vegetable oils, focusing instead on oils certified as “deforestation-free.” This approach, in the case of palm oil, could cut emissions by up to 92%, highlighting the need for strategies that support sustainable agriculture and the global food system.

Palm oil has been heavily criticized for its role in the deforestation of primary tropical forests, particularly in Malaysia and Indonesia. This deforestation has led to significant biodiversity loss and increased greenhouse gas emissions.

As a result, many food products are now advertised as “palm oil-free,” prompting producers to stop using palm oil and instead increase their demand for alternative vegetable oils.

A recent study conducted by researchers from CMCC and Politecnico di Milano delves into the environmental impacts of replacing palm oil with other vegetable oils. Titled “Deforestation and greenhouse gas emissions could arise when replacing palm oil with other vegetable oils” and published in the journal Science of the Total Environment, the study examines the potential consequences of substituting palm oil with soybean, rapeseed, and sunflower oils on a global scale.

The study explores scenarios where 25%, 50%, and 100% of the current palm oil usage is replaced with soybean, rapeseed, and sunflower oils. It analyzes the potential impact on land use changes, forest carbon stock losses, and resulting greenhouse gas emissions from substituting palm oil with alternative vegetable oils.

While these alternatives show lower agricultural inputs and emissions per unit of production, they demand more land. “But where do we find this additional land?” says CMCC researcher Maria Vincenza Chiriacò, first author of the study. “This expansion in land use could lead to deforestation in other regions, transferring the problem rather than solving it.”

Replacing palm oil with other vegetable oils would require much more land due to their lower yield per hectare. The researchers estimate that this shift could endanger between 28 to 52 million hectares of forest across the eight major producing countries analyzed (Argentina, Brasile, Canda, Cina, India, Russia, Ukraine, USA). This land conversion would likely offset any emissions savings from reduced agricultural inputs, maintaining or even exacerbating deforestation and emissions issues.

“Replacing it with other oils could lead to further deforestation issues,” says Maria Vincenza Chiriacò. “Our research proves that the best solution is to use palm oil as long as it is certified ‘deforestation-free’.”

“Such certifications ensure that oils are produced on lands that are not forests, such as existing agricultural lands or marginal lands already designated for agriculture, or on land that has not been recently deforested, thereby minimizing environmental harm” says Monia Santini, Director of CMCC’s Institute for Climate Resilience (ICR) and another author of the study. The study shows that if the total amount of palm oil was certified as deforestation-free, emissions from its production could drop by 92%, reducing from 372 million tonnes to around 29 million tonnes of CO₂eq.

To assess land suitability for alternative oil crops, the study utilized data from the FAO’s Global Agro-Ecological Zones (GAEZ) and other datasets, combining Life Cycle Assessment (LCA) with Land Use Change (LUC) emissions for a comprehensive view. This approach provides insights into both emissions from agricultural practices and the impacts of land conversion.

“We aim to extend these analyses to future scenarios beyond 2050, considering the impacts of climate change and the feasibility of adopting diets recommended by the EAT-Lancet Commission for planetary health,” says Chiriacò. “This will explore whether the projected land use changes are sustainable in the long term and how they would align with global dietary needs, in a world with a growing population and a changing climate.”

More information:

• The global production of vegetable oils and climate change – CMCC webinar
• Maria Vincenza Chiriacò, Nikolas Galli, Monia Santini, Maria Cristina Rulli, Deforestation and greenhouse gas emissions could arise when replacing palm oil with other vegetable oils, Science of The Total Environment, Volume 914, 2024, 169486, ISSN 0048-9697, https://doi.org/10.1016/j.scitotenv.2023.169486.