Annual cycle of air temperature: amplitude of the annual harmonic

The 1st harmonic has > 90 % of variance of daily temp. in the extra-tropics.

Amplitude is larger in higher latitude.
Amplitude is larger in interior of continetns.
Asymmetry in Eurasia: maximum in east Siberia.
Based on daily max. and min. temperature from Oct. 1997 to Dec. 1991 of Global Daily Summary compiled by U.S. National Climatic Data Center in 1994.