Comparing The Response Of Simulated Sugarcane Growth To Climate Change.

Sugarcane is an important crop in the tropics and sub-tropics, contributing to substantially to livelihoods in these regions. However, despite its importance, there is little information of the effect of climate change on sugarcane either at a physiological or farming system level. There are a number of models of sugarcane growth that incorporate information and/or assumptions about the crop’s response to water and temperature stress and elevated atmospheric CO₂ concentration, and these models may provide insights into the response, and uncertainty in this response, to climate change effects. In this paper we examine simulation of growth and development of sugarcane crops under typical management conditions at three contrasting sites: irrigated crops at Ayr, Australia; and rainfed crops at Piracicaba, Brazil and La Mercy, South Africa. Simulations were conducted for both historical daily climate records, and future climate scenarios with higher atmospheric CO₂ concentrations. The study focussed on the DSSAT-Canegro and APSIM-Sugar models, the two most widely tested and applied sugarcane models. The simulations by the two models were conducted using the common protocol approach outlined in the AgMIP program. As well as comparing the different responses in the two models, we discuss some of the difficulties in undertaking model crop model intercomparisons against common data sets.