evidence: We now redo this analysis for window lengths of 10–30 years, to see if there is any dependence of the rate increase on the chosen window. Panel c shows the resulting regression coefficients. For all trend windows longer than about 20 years, we find a consistent rate increase for the filtered data. The 5–95% confidence intervals (error bars) also decrease markedly with the length of the fit window, and is strongly reduced by the filtering procedure. The raw data also show an increasing warming rate, but with greater uncertainty and with stronger influence of annual-to-decadal scale internal variability. We also note that the raw data consistently shows a stronger rate increase than the filtered data, indicating differences in the amount of warming filtered through the time period. While the reasons for this require further investigation, it may be due to a systematic shift in SST patterns over the period of study.