Abstract We address the uncertainty related to cross-correlation waveform time shift measurements, particularly related to temporal changes in inner core seismic waves. Details of the cross-correlation measurement, including data processing, window length, pick time, sampling rate and the algorithm itself, all affect the calculated time shift. By systematically varying measurement parameters for a set of earthquake doublets we find time shift uncertainties of 0.01 s and 0.02 s for differential times and double differential times respectively. The uncertainty is of a similar magnitude to reported double differential times of PKIKP and PKiKP inner core phases. Accounting for measurement uncertainty results in 80% of values published in a recent study being below the measurement resolution ( Yang and Song 2020a ). While the temporal variations in inner core phases is not in dispute, properly accounting for uncertainties is needed for robust data interpretation. A re-assessment for the origin of inner core temporal changes is therefore warranted and future studies should account for measurement uncertainty.

中文翻译：

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波形相关测量不确定度对内核地震波时间变化的影响

摘要 我们解决了与互相关波形时移测量相关的不确定性，特别是与内核地震波的时间变化相关的不确定性。互相关测量的细节，包括数据处理、窗口长度、拾取时间、采样率和算法本身，都会影响计算出的时移。通过系统地改变一组地震双峰的测量参数，我们发现微分时间和双微分时间的时移不确定性分别为 0.01 s 和 0.02 s。不确定性与所报告的 PKIKP 和 PKiKP 内核相的双微分时间具有相似的幅度。考虑到测量不确定性，最近一项研究中发表的 80% 的值低于测量分辨率（Yang 和 Song 2020a）。虽然内核阶段的时间变化没有争议，但需要适当考虑不确定性以实现可靠的数据解释。因此，有必要重新评估内核时间变化的起源，未来的研究应考虑测量的不确定性。