The cumulative absolute absement (CAA) of the 3 s window after P-wave arrival can be used to estimate the magnitude ( $${M}_{CAA}$$ ) of an earthquake. This method can achieve good results even when only the six stations nearest to the epicenter are used. The standard deviation between the estimated CAA magnitude ( $${M}_{CAA}$$ ) and the moment magnitude ( $${M}_{w}$$ ) is found to be 0.3 when using either 6 or 20 stations. This means that $${M}_{CAA}$$ can be reliably predicted using the closest 6 stations. On the other hand, the magnitude ( $${M}_{Pd}$$ ) derived from $${P}_{d}$$ using the closest 20 stations has a standard deviation of 0.4 between the estimated $${M}_{Pd}$$ and $${M}_{w}$$ . This suggests that CAA is a better magnitude determination parameter for the EEW system than $${P}_{d}$$ .

中文翻译：

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利用累积绝对绝对震级确定地震预警震级

P波到达后3秒窗口的累积绝对绝对距（CAA）可用于估计地震震级（ $${M}_{CAA}$$ ）。即使仅使用距离震中最近的六个台站，该方法也能取得良好的效果。当使用 6 个或 20 个站点时，估计的 CAA 震级 ( $${M}_{CAA}$$ ) 和矩震级 ( $${M}_{w}$$ ) 之间的标准偏差为 0.3 。这意味着可以使用最近的 6 个站点可靠地预测 $${M}_{CAA}$$。另一方面，使用最近 20 个台站从 $${P}_{d}$$ 得出的震级 ( $${M}_{Pd}$$ ) 与估计的 $${ 之间的标准差为 0.4 M}_{Pd}$$ 和 $${M}_{w}$$ 。这表明对于 EEW 系统来说，CAA 是比 $${P}_{d}$$ 更好的震级确定参数。