Downscaling Global Climatic Predictions to the Regional Level: A Case Study of Regional Effects of Climate Change on Wheat Crop Production in Victoria, Australia

Significant change in wheat production across the state of Victoria, Australia is predicted if the climate changes according to the Inter‐governmental Panel on Climate Change (IPCC) scenarios. Most critical to the dry areas are scenarios of reduced rainfall. For the more arid zones sowing a faster maturing type (cv. Silverstar) on the 1 June resulted in the best outcome with some small gains and losses predicted. Sowing earlier or later resulted in yield losses of around 10 to 20%. In the wetter areas of southern Victoria, consistent gains in yield of around 10‐20% should occur in all cultivar types (e.g. Silverstar, Chara or Mackellar), but only from later sowing times (July to August). Despite the greater uncertainty in climate models compared to crop models, in the context of moderate temperature rise of about 2 degrees, we expect that wheat crop phenological development can be re‐engineered towards slower‐developing spring types to maximize grain yield under future climate scenarios across Victoria.