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The Outlook for Sugarcane Production in Brazil: How Sweet It Is!
Marin, F.R., Jones, J.W., Singels, A., Royce, F., Assad, E.D., Pellegrino, G.Q. and Justino, F. 2013. Climate change impacts on sugarcane attainable yield in southern Brazil. Climatic Change 117: 227-239.

Citing Rosenzweig et al. (2012), the authors write that the primary challenges faced by the agricultural sector under predicted climate change scenarios are "to provide food security for an increasing world population while protecting the environment and the functioning of its ecosystems." And in this regard, they go on to indicate that "impacts on agriculture have special importance for Brazil, since nearly 30% of Brazilian gross national product is related to agribusiness," citing Barros (2009). Fine-tuning this concern even more, they further note that "Brazil is the world's largest sugarcane producer," and that "the State of Sao Paulo produces nearly 60% of Brazilian sugarcane under rain-fed conditions."

What was done
Marin et al. evaluated the effects of climate change on sugarcane yield, water use efficiency, and irrigation needs in southern Brazil, based on downscaled outputs of two general circulation models (PRECIS and CSIRO) and a sugarcane growth model (DSSAT/CANEGRO) that was calibrated for the main cultivar currently grown in Brazil, based on five field experiments conducted under several soil and climate conditions, where the sensitivities of simulated stalk fresh mass (SFM) to air temperature, CO2 concentration and rainfall were also analyzed.

What was learned
The seven scientists report that their analyses yielded increases in simulated SFM and water use efficiency (WUE) for all scenarios investigated. "On average," for example, they found that "for the current sugarcane area in the State of Sao Paulo, SFM would increase 24% and WUE 34% for rain-fed sugarcane." And they say that "considering the current technological improvement rate, projected yields for 2050 ranged from 96 to 129 tons per hectare, which are respectively 15 and 59% higher than the current state average yield." Also, in their concluding remarks, they say their simulations suggest that "the WUE increase due to higher CO2 seems to be the main cause for the positive simulated yield response."

What it means
Refreshingly, as opposed to the standard hand-wringing of the climate-alarmist crowd, in regard to climate-model-inspired projections of coming climatic catastrophes, due to earth's still-rising atmospheric CO2 concentration, it's CO2 to the rescue!

Barros, G. 2009. Brazil: the challenges in becoming an agricultural superpower. In: Brazil As An Economic Superpower? - Understanding Brazil's Changing Role in the Global Economy. Brookings, Washington, DC, U.S.A.

Rosenzweig, C., Jones,J.W.,Hatfield,J.L.,Ruane,A.C.,Boote,K.J.,Thorburn, P., Antle, J., Nelson,G., Porter, C., Janssen, S.,Asseng,S., Winter,J.M., Greeley, A.P., Basso, B. and Ewert, F. 2012. The Agricultural Model Intercomparison and Improvement Project (AgMip): Protocols and pilot studies. Agricultural and Forest Meteorology 170: 166-182.

Reviewed 23 October 2013