Solar Cycle Signal in Air Temperature in North America: Amplitude, Gradient, Phase and Distribution

Abstract

The ll-year solar cycle temperature signal in records from North America is further elucidated by single- and two-channel (Morf et al., 1978) high-resolution signal processing. In agreement with earlier analysis (Currie, 1979) the signal T_e, is found only at locations cast of the Rocky Mountains and north of 35 =° N. Revised estimates of mean amplitude and latitude gradient are 0. 18 =° C and 0. 13 = ± 0.03°C per 10³km. respectively. New results are as follow: In view of the recently detected 11-year term in earth rotation ΔT = ET - UT (Currie, 1980), cross spectra of temperature records with ΔT were computed. At the solar cycle period T_e, lags ΔT by 3.0 =± 0.7 years; since ΔT lags the change in length of day Δ(lod) by 2.7 years and Δ(lod) is in phase with sunspot numbers R_z, (Curric, 1981b), the result is that T_e lags R_z, by 5.7 ± 0.7 years.