Beneficial impacts of climate change on pastoral and broadacre agriculture in cool-temperature Tasmania
Phelan, DC and Parsons, D and Lisson, SN and Holz, GK and MacLeod, ND, Beneficial impacts of climate change on pastoral and broadacre agriculture in cool-temperature Tasmania, Crop and Pasture Science, 65, (2) pp. 194-205. ISSN 1836-0947 (2014) [Refereed Article]
Although geographically small, Tasmania has a diverse range of regional climates that are affected by different
synoptic influences. Consequently, changes in climate variables and climate-change impacts will likely vary in different
regions of the state. This study aims to quantify the regional effects of projected climate change on the productivity of rainfed
pastoral and wheat crop systems at five sites across Tasmania. Projected climate data for each site were obtained from the
Climate Futures for Tasmania project (CFT). Six General Circulation Models were dynamically downscaled to ~10-km grid
cells using the CSIRO Conformal Cubic Atmospheric Model under the A2 emissions scenario for the period 1961–2100.
Mean daily maximum and minimum temperatures at each site are projected to increase from a baseline period (1981–2010) to
2085 (2071–2100) by 2.3–2.7°C. Mean annual rainfall is projected to increase slightly at all sites. Impacts on pasture and
wheat production were simulated for each site using the projected CFT climate data. Mean annual pasture yields are projected
to increase from the baseline to 2085 largely due to an increase in spring pasture growth. However, summer growth of
temperate pasture species may become limited by 2085 due to greater soil moisture deficits. Wheat yields are also projected to
increase, particularly at sites presently temperature-limited. This study suggests that increased temperatures and elevated
atmospheric CO2 concentrations are likely to increase regional rainfed pasture and wheat production in the absence of any
significant changes in rainfall patterns.