Intraseasonal Forecasting of the 2009 Summer and Winter Australian Heat Waves Using POAMA
Intraseasonal Forecasting of the 2009 Summer and Winter Australian Heat Waves Using POAMA
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DOI：
10.1175/waf-d-10-05041.1
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发表时间：
2011-06-01
影响因子：
2.9
通讯作者：
Alves, O.
中科院分区：
文献类型：
--
作者：
Hudson, D.;Marshall, A. G.;Alves, O.
2009年夏季（1月27日至2月8日）和冬季（8月14日至31日）期间，澳大利亚南部和东部大部分地区发生了极端热浪。夏季热浪导致澳大利亚东南部地区多次创下气温记录，并在维多利亚州引发毁灭性的丛林大火，造成人员伤亡和财产损失。冬季热浪主要影响澳大利亚东部的亚热带地区，并对农业产业造成重大破坏。在这项研究中，评估了气象局动态季节预测模型——澳大利亚预测海洋大气模型（POAMA）预测热浪对应的两个时期（分别为1月25日至2月7日和8月15日至28日）的每两周平均值的能力。预测基于 10 名成员的每日滞后集合预测，在验证日期前 30 天进行初始化。评估集合平均值和概率预测。该论文是一项更大规模研究的一部分，该研究调查了 POAMA 的使用，以填补澳大利亚天气预报和季节性展望之间当前的预测能力差距。最成功的预测是在验证日期前两周初始化的，当时 POAMA 展示了预测澳大利亚东南部夏季事件和冬季事件澳大利亚中部和东部广泛变暖的能力。在这些提前时间内，集合平均预报捕捉到了澳大利亚上空对流层中层副热带反气旋异常，这是两次热浪的特征。然而，集合平均预测中白天变暖峰值的幅度被低估了，对于夏季热浪来说更是如此，而且最大变暖发生在比这两个事件中观察到的更远的东部。 POAMA能够预测与冬季热浪预测验证日期前0-9天初始化的集合中观察到的东南部温度异常类似的情况，从而对澳大利亚东南部的粮食产区具有潜在的好处。
Extreme heat waves occurred over much of southern and eastern Australia during the summer (27 January-8 February) and winter (14-31 August) of 2009. The summer heat wave resulted in many temperature records across southeastern Australia, as well as devastating bushfires in Victoria that caused losses of life and property. The winter heat wave primarily affected subtropical areas of eastern Australia and produced major disruptions to agricultural industries. In this study the ability of the Bureau of Meteorology's dynamical seasonal prediction model, the Predictive Ocean Atmosphere Model for Australia (POAMA), to forecast fortnightly means for two periods corresponding to the heat waves (25 January-7 February and 15-28 August, respectively) is assessed. The forecasts are based on 10-member daily lagged-ensemble forecasts, initialized up to 30 days prior to the verification date. Ensemble mean and probabilistic forecasts are assessed. The paper forms part of a larger study investigating the use of POAMA for filling the current prediction capability gap between weather forecasts and seasonal outlooks for Australia. The most successful forecasts were initialized up to 2 weeks prior to the verification date, when POAMA demonstrated the ability to predict widespread warming over southeastern Australia for the summer event and over central and eastern Australia for the winter event. At these lead times, the ensemble mean forecast captured the midtropospheric subtropical anticyclonic anomaly over Australia that characterized both heat waves. The magnitude of the peak daytime warming in the ensemble mean forecast was, however, underpredicted, more so for the summer heat wave, and maximum warming occurred farther east than observed in both events. POAMA was able to predict temperature anomalies similar to those observed over the southeast in the ensemble initialized 0-9 days prior to the forecast verification date for the winter heat wave, thus being of potential benefit to the grain-producing regions of southeastern Australia.