Hydroclimatic projections for the Murray‐Darling Basin based on an ensemble derived from Intergovernmental Panel on Climate Change AR4 climate models

摘要: [1] We assess hydroclimatic projections for the Murray-Darling Basin (MDB) using an ensemble of 39 Intergovernmental Panel on Climate Change AR4 climate model runs based A1B emissions scenario. The raw output precipitation, P, was adjusted a quantile-based bias correction approach. We found that projected change, ΔP, between two 30 year periods (2070–2099 less 1970–1999) little affected by correction. range ΔP among models large (∼±150 mm yr−1) with all–model run and all-model averages (4.9 −8.1 near zero, against background climatological P ∼500 yr−1. time series actually observed annual over MDB indistinguishable from generated purely random process. Importantly, nearly all showed similar behavior. used these facts to develop new approach understanding variability in ΔP. By plotting versus variance series, we could easily identify were beyond bounds expected variations. For MDB, anticipate process lead differences ±57 yr−1 (95% confidence) successive periods. This is equivalent ±11% translates into variations runoff around ±29%. sets baseline gauging modeled and/or changes.