In the last five centuries, Portugal was affected by several earthquakes of strong magnitude (M > 7) that caused widespread destruction and a significant death toll. Due to the geographical distribution of moderate-to-strong magnitude events along the Tagus Valley and Southwest of the country, an earthquake early warning system might potentially provide precious warning time ahead of the arrival of the destructive seismic waves. We used a probabilistic seismic hazard model to generate a large stochastic event set for the country, and evaluated the probability of triggering correct and false alerts considering different ground shaking thresholds. We propagated the aleatory variability related to the estimation of the location and event magnitude, as well as the variability in the ground shaking across the Portuguese territory. For the events for which a correct alert would be expected, we estimated the warning time for each district, considering various sources of latency. These analyses were performed considering the current seismic network of the country, as well as the potential installation of submarine sensors as part of the forthcoming renewal of the communication cables between mainland Portugal and the archipelagos of Azores and Madeira. The results indicate that for the districts located in the Southwest of the country, an earthquake early warning system might provide sufficient warning time for risk mitigation measures to be followed.

在过去的五个世纪里，葡萄牙受到了几次强烈地震（M > 7）的影响，造成了广泛的破坏和大量的死亡人数。由于塔霍河谷和该国西南部的中等至强震级事件的地理分布，地震预警系统可能会在破坏性地震波到来之前提供宝贵的预警时间。我们使用概率地震危险模型为该国生成了一个大型随机事件集，并评估了考虑不同地震动阈值的触发正确和错误警报的概率。我们传播了与位置和事件幅度估计相关的偶然变化，以及整个葡萄牙领土的地面震动变化。对于预期会发出正确警报的事件，我们估计了每个地区的警报时间，并考虑了各种延迟来源。这些分析是考虑到该国当前的地震网络，以及作为即将更新葡萄牙大陆与亚速尔群岛和马德拉群岛之间通信电缆的一部分而可能安装的海底传感器。结果表明，对于位于该国西南部的地区，地震预警系统可以为采取风险缓解措施提供足够的预警时间。以及作为即将更新的葡萄牙大陆与亚速尔群岛和马德拉群岛之间通信电缆的一部分，可能安装海底传感器。结果表明，对于位于该国西南部的地区，地震预警系统可以为采取风险缓解措施提供足够的预警时间。以及作为即将更新的葡萄牙大陆与亚速尔群岛和马德拉群岛之间通信电缆的一部分，可能安装海底传感器。结果表明，对于位于该国西南部的地区，地震预警系统可以为采取风险缓解措施提供足够的预警时间。