On the trend of Atlantic Hurricane with Cosmic Rays
Abstract
One of the main goals of Solar-Terrestrial Physics is to know how and when the periodicities of Solar Activity do modulate terrestrial Climatic changes? The purpose of this study is to examine the cosmophysical periodicities that could possible be related with a modulation in the number and magnitude of hurricanes. Previous efforts on elucidating a plausible contribution of cosmophysical phenomena in the process of hurricanes development have been mostly based on Correlational analysis. Such an analysis indicates the possibility of a certain relation between two time series, however, this is of global nature and does not furnish a precise information about when such a relation occurs: the fact that two series (cosmophysical and climatic) have similar periodicities does not necessarily implies that one is the cause and another is the effect. Besides, even if the correlation coefficient is very low, there is the possibility that an existing relation could be of non linear nature, or there is a strong phase shift among both phenomena. One of the ways to analyze two non-stationary series, to discern whether there is a linear relation or not is by means of the Coherence Wavelet method, which furnish valuable information about when and which periodicity do coincide in time, and about its nature, linear or non- linear relation, provided there is not a noticeable diphase among them. In the present work we use the Morlet wavelet technique for the annual number of North Atlantic hurricanes between 1851 and 2005.. The periodicities found from this analysis, with > 95 % confidence level are of 3.5, 5.5 and 7 yrs., and with ? 95 % confidence level are of 22 and 30 yrs. All these periodicities, are known in Cosmic Rays physics to be a consequence of Solar Activity modulation. To find the relationship between hurricanes and Cosmic Ray series in time-frequency space, we use then Wavelet Coherence analysis: it is found that the more prominent periodicity in the case of hurricanes of magnitude 3 and 4 is that of 30 years. The relationship with hurricanes of magnitude 3 is a non-linear one in the period 1891-1944, with a coherence > 0.9, while for hurricanes of magnitude 4 there is a linear relation between 1889 and 1953 with a coherence of 0.9. . It is worth noting that Tropical Storms landing into Mexico, the Total Cyclonic Energy , as well as the number of category 4-5 in the Northwest Pacific basin and the Potential Destruction Index , all them present also a cyclic behavior of 30 years.
- Publication:
-
International Cosmic Ray Conference
- Pub Date:
- 2008
- Bibcode:
- 2008ICRC....1..785P