Extended Data Fig. 4: Spectral estimates from tree ring based and long instrumental temperature series.
From: Millennial-scale climate variability over land overprinted by ocean temperature fluctuations
To test whether the transition from the weakly scaling macroweather regime to the stronger scaling oceanic regime is also visible from independent temperature reconstructions, we show the spectral estimates of land temperature variability from tree ring width (TRW), maximum latewood density (MXD) measurements and long (>170 years) instrumental series together with the pollen-based reconstructions (solid); logarithmically spaced axes were used. The spectral estimates from the BEST gridded instrumental data is provided as reference at the corresponding locations (dashed, detrended with respect to log(CO2)). The MXD and long instrumental spectra support the scaling of the pollen data. The TRW spectra deviates at high and low frequencies due to the known biases of this proxy85,86,87 (see Supplementary Information Note 1).
