| Summary: | We review the history of analyses of the tide-gauge record for Churchill, Manitoba, and advance a new analysis of the record using a longer time series than that available to Tushingham (1992). The sensitivity of the mean rate of relative sea-level change obtained to the averaging procedure employed is demonstrated by calculating rates for sliding observation intervals of variable widths. After that, the 'best' mean rate of relative sea-level rise is compared with estimates of the mean rate of land uplift and the mean rate of gravity change based on GPS and absolute gravimetry data, respectively. As an additional type of observation, the postglacial relative sea-level change obtained from paleo-shoreline evidence in the Churchill region is also included. Assuming that the governing process is glacial-isostatic adjustment, a joint inversion of the four types of data return upper- and lower-mantle viscosities of about $3 imes 10^{20}$ Pa s and $> 5 imes 10^{21}$ Pa s, respectively.
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