Classification of climate in the northern hemisphere by the envelope of temperature signals

The authors developed the algorithm based on analytic signal theory, allowing grouping geophysical signals over various spatial and temporal scales. Surface temperature was selected as an integrated indicator of climate change. Algorithm can distinguish the climatic structures where multi-year temperature oscillations are congruent. To accomplish that, the information on temperature series amplitude temporal changes was used. Computing technology developed was applied to the data from 818 northern hemisphere meteorological stations over the period of 1955-2010. The classification for three correlation thresholds was obtained. Distinguished structures have strict geographical differentiation and defined by the highest synchronism level of temperature oscillations. Stations closest to each other spatially demonstrate the highest strength of relationship to typical class envelope.