One controversy, three conflicting calculation models
Given the crisis resulting from the release of Sciencexpress’ article in 2008 authored by Searchinger of Princeton University, a uniform method of assessing the levels of greenhouse gases resulting from bioethanol production needed to be conceived of. When deciding whether agricultural land is suitable to be converted into sugar-cane fields, a variety of factors need to be now taken into consideration. Multiple factors need to be assessed in order to decide whether the decision is a valid one and whether the shift in use will result in a higher or lower carbon footprint.
Scientists and policy makers have therefore created models in order to establish the successfulness of the exchange in a linear and clear manner. The four main models discussed below form the center of the debate and are the most widely employed. It is worth mentioning, however, that additional models such as Banse and GTAP exist, even if not employed in a meaningful enough way to have an impact on the discussion.
In Brazil, the most commonly employed model is the International Food Policy Research Institute Model (IFPRI), which is a computable general equilibrium model. This is the model employed by UNICA, the Brazilian Sugarcane Industry Association, in their assessments and is strongly defended by their CEO, Marcos Sawaya Jank.
The European Union, on the other hand, uses a different model in order to assess their position towards the shift in land use. The EU model is known as the Joint Research Center Model (JRC) – or the AGLink model – created by the academic institution associated with the EU itself. The EU uses this model in its trade positions with Brazil when deciding whether the bioethanol produced is sustainable and therefore “considers a larger volume of biofuels than IFPRI” according to the 2010 article, written by H.J Croezen (et al), titled Biofuels: Indirect Land Use Change and Climate Impact.
In America, they employ their own model created by, and named after, the Environmental Protection Agency (EPA). However, the state of California and Governor Jerry Brown, felt that this national model did not go far enough and therefore created their own. The Californian Air Resources Board Model (CARB) was consequently published in 2011 to establish the level of sustainability of bioethanol production for California’s Low Carbon Fuel Standard (LCFS II).
Each model calculations differ drastically and consequently the IFPRI model shows the lowest levels of greenhouse gases being released by the bioethanol process at 38 g/MJ while the CARB shows the highest at 69g/MJ. Therefore the IFPRI model has become associated with big agribusiness since when employed, it shows the majority of fields to be appropriate to cultivate sugarcane. CARB, on the other hand, is the most environmentally conservative model since it is considerably less likely to approve the shift in land use based on the resulting emissions levels.
Those relying on the IFPRI model nevertheless maintain its scientific accuracy and argue that it does not favour business. They say that there are inherent problems in calculating the emissions levels, which leads to the differing results. These difficulties include the fact that the readings produced are a momentary snapshot and therefore are too static to be reliable, that there is a lack of real data (meaning that assessors are too dependant on models which reinforce inaccuracies) and, lastly, that the continual shift of government in regards to bioethanol mean that the data is continually shifting.
Many differing actors believe that such contention cannot continue and that in order to have a meaningful discussion of the true environmental impact of Brazilian bioethanol production from sugarcane, a global model must be created. This model has been named the IIASA model and is an amalgamation of the IFPRI and JRC models. Having all states involved adopt this one universal model would mean that a consistent policy towards land use change could be adopted and therefore better agricultural planning could be achieved.