Statistical analysis of Tokyo winter temperature approximations, 1443–1970

Abstract

Spectral analysis of winter temperatures in Tokyo from 1443‐1970, based to 1870 on Lake Suwa freezing dates and since then on observations, shows significant contributions to variance in the 2.1, 3.0, 10.9 and 21.7 years bands. Consecutive thirty year means show very little variation. The coldest period was between 1489 and 1528. There is no notable variation during the so‐called Maunder sunspot minimum.