A potential century–scale rhythm in six major palaeoclimatic records in the northern hemisphere

Abstract.

Six millennial proxy records of temperature in the northern hemisphere were analysed using both the Fourier and wavelet approaches. We found that the analysed temperature proxies have appreciable synchrony at multidecadal and centennial time scales. These data also show evidence for the presence of a roughly regular large‐scale rhythm with a periodicity of 50–130 years in the climate of the northern hemisphere over the last millennium. It is shown that the amplitude of this variation might reach 0.20–0.28°C and contribute appreciably to the rise of global temperature over the first part of the 20th century. Possible origins of the global centennial climatic cycles are discussed.

Key words:

• palaeoclimatology
• climatic variability
• dendroclimatology