Method provides carbon footprint data at municipal level

A new version of the BRLUC (Brazilian Land Use Change) method provides carbon footprint data for various agricultural products at the municipal level for the whole of Brazil. The data available is about the “Land use change” process (or LUC in English), which can account for up to 90% of the carbon footprint of these products and which was responsible for approximately 66% of CO2 emissions in Brazil in 2020.

Accounting for land use change is required in the vast majority of international carbon footprint and life cycle assessment (LCA) protocols, such as the GHG protocol and ISO standards on the topic. In general, they require that, when studying a given product, the land use was observed 20 years before and the difference in carbon stock between this previous use and current use.

For example, if the objective of the study is to assess the carbon footprint of an agricultural product and the land use at the production site was forest or pasture 20 years ago, it is necessary to account for this difference in carbon stock and the resulting CO2 emissions. of this stock change. “The carbon stocks of a forest can be up to seven times greater than those of a crop. So, if this conversion occurred over a period of 20 years, emissions could be very high”, explains Danilo Garofalo, innovation fellow at Embrapa Meio Ambiente and first author of the study.

"The ideal in these studies is to collect data at the field or farm level, but this is often unfeasible, either due to lack of information or the high costs and time involved. The BRLUC method was developed to meet this need, making data available at municipal level, in an open manner and in accordance with international protocols", says Renan Novaes, an analyst at Embrapa Meio Ambiente and one of the method's co-authors.

The new method and new emissions estimates were published in one of the main magazines dealing with the topic of LCA in the world, the Journal of Cleaner Production, which has a high JCR impact factor of 11,0 and is available using this link. The data for the period 2000-2019 is also open access on the Embrapa website at https://brluc.cnpma.embrapa.br/

In addition to authors from Embrapa, the work included the participation of Miguel Brandão, from the KTH Royal Institute of Technology, Sweden, and Julia Zanin Shimbo, from the Amazon Environmental Research Institute (Ipam) and scientific coordinator of MapBiomas. “Publication in high impact factor journals like this one is important to give greater visibility and credibility to the studies carried out, as they go through rigorous peer review processes and scientific criteria”, says Brandão.

The main improvements made in this new version, called BRLUC 2.0, were the use of spatially explicit land conversion data from MapBiomas, agricultural statistics from the Brazilian Institute of Geography and Statistics (IBGE), regionalized carbon stocks from recognized sources such as IPCC and national greenhouse gas inventory and a shared responsibility approach between crops. “With these improvements, emissions are estimated with greater accuracy and will be used to replace estimates made internationally with coarser data”, says researcher Marília Folegatti, from Embrapa Meio Ambiente.

The most recent version of the method led to an estimate of 911 Mtons of CO2  associated with agriculture in 2019, 81% of which were related to planted pastures. Land use change emission rates in Brazil for sugarcane, corn and soybeans were estimated at 0,3, 2,0 and 2,3 tCO2.ha-1.year-1, respectively. “These new estimates are 97%, 38% and 85% lower than the estimates available in the Blonk consultancy tool and in the GFLI and Agrifootprint databases”, which are examples of data available internationally. “After the publication of the article, we already had confirmation of interest in incorporating our estimates into important international databases”, emphasizes Marília.

“With the growing commitment of governments and companies to carbon reduction targets, such as net-zero goals, this type of data will be increasingly requested. As the resulting data are consistent with international protocols, they can be used by these studies”, highlights Novaes. The authors hope that the data will also be used to support the management of companies' supply chains, towards a low-carbon production profile and greater international competitiveness.

The study was financed with public resources from Embrapa and the Ministry of Mines and Energy (MME) and co-financed by four private sector associations: the Animal Food Industries Union (Sindirações), the Brazilian Animal Protein Association (ABPA), the Brazilian Association of Vegetable Oil Industries (Abiove) and the Brazilian Association of Soy Producers (Aprosoja). A potential conflict of interest was mitigated by the following actions: selection of scholarship holders independently by the Embrapa team; prior submission of hypotheses, methods and results for scrutiny by independent researchers; submission of work to a high-impact peer-reviewed journal; and the non-involvement of associations in these decisions.

The authors of the article are Danilo F. Trovo Garofalo, Renan Milagres L. Novaes, Ricardo A. A. Pazianotto, Vinícius Gonçalves Maciel and Marília I. S. Folegatti-Matsuura from Embrapa Meio Ambiente (Jaguariúna, SP), Miguel Brandão from KTH Royal Institute of Technology Stockholm ( Sweden) and Julia Zanin Shimbo from the Amazon Environmental Research Institute (Ipam).

Access to the article in the Journal of Cleaner Production at:

 https://www.sciencedirect.com/science/article/pii/S0959652622021503

Access to BRLUC 2.0: 

https://brluc.cnpma.embrapa.br/