Temperature variability in central Mexico and its possible association to solar activity

Minimum extreme temperature variability from five meteorological stations i n the central part of Mexico covering a period from similar to 1920 to simi lar to 1990 is examined. We found a correlation coefficient (r = 0.65) betw een these temperature records and geomagnetic activity. Furthermore, by per forming spectral analysis peaks were obtained with similar periodicities to those found in the sunspot number, the magnetic solar cycle, cosmic ray fl uxes and geomagnetic activity; all of these phenomena are modulated by sola r activity. Signals with periodicities comparable to those observed in El N ino and the Quasi-Biennial Oscillation were also identified. We conclude th at the solar signal is probably present in the minimum extreme temperature record of the central part of Mexico. (C) 2001 Elsevier Science Ltd. All ri ghts reserved.