scostep 2010 (stp12) - Leibniz-Institut für Atmosphärenphysik an der ...

STP12 Abstracts
Berlin, 12 - 16 July 2010
SCOSTEP Symposium 2010
A 22-yrs Hurricane Cycle and its Relation to Geomagnetic Activity
Mendoza Blanca 1 , Pazos Marni 2
1 Instituto de Geofisica, Universidad Nacional Autonoma de Mexico, 2 Posgrado en Ciencias de la
Tierra, Universidad Nacional Autonoma de Mexico
Applying spectral analysis to the Atlantic and Pacific hurricane time series, we found
periodicities that coincide with the main sunspot and magnetic solar cycles. To assess the
possibility that these periodicities could be associated to solar activity, we obtain correlations
between hurricane occurrence and several solar activity-related phenomena, such as the total
solar irradiance, the cosmic ray flux and the Dst index of geomagnetic activity. Our results
indicate that the highest significant correlations are found between the Atlantic and Pacific
hurricanes and the Dst index. Most importantly, both oceans present the highest hurricane-
Dst correlations during the ascending part of odd solar cycles and the descending phase of
even solar cycles. This shows not only the existence of a 22yrs cycle but also the nature of
such periodicity. Furthermore, we found that the Atlantic hurricanes behave differently from
the Pacific hurricanes in relation to the solar activity-related disturbances considered.